A&P Midterm Review Chapter 17-22 PDF

A&P Midterm Review Chapter 17-22 Audio Review Chapter 17 Islets of Langerhans: (Pancreas) ○ Alpha Cells: Produce glucagon, increasing blood glucose. ○ Beta Cells: Produce insulin, decreasing blood glucose. ○ Delta Cells: Produce somatostatin, regulating insulin and...

A&P Midterm Review Chapter 17-22 Audio Review Chapter 17 Islets of Langerhans: (Pancreas) ○ Alpha Cells: Produce glucagon, increasing blood glucose. ○ Beta Cells: Produce insulin, decreasing blood glucose. ○ Delta Cells: Produce somatostatin, regulating insulin and glucagon. Endocrine vs. Exocrine Glands Endocrine Glands: Release hormones directly into the bloodstream (e.g., thyroid gland). Exocrine Glands: Release secretions through ducts to an epithelial surface (e.g., sweat glands). Insulin receptors are proteins located on the surface of cells that bind insulin, a hormone crucial for regulating glucose levels in the blood Glycogen is made up of glucose units linked together, (long necklaces of glucose)and its structure allows for quick breakdown into glucose when the body requires energy. Glucagon is a hormone produced by the alpha cells of the pancreas. (the scissors that cut the necklace ) Its primary role is to raise blood glucose levels by promoting the conversion of glycogen to glucose in the liver and stimulating gluconeogenesis, the process of producing glucose from non-carbohydrate sources. Glucagon acts as a counter-regulatory hormone to insulin, which lowers blood glucose levels. It plays a crucial role in maintaining energy balance, especially during fasting or intense physical activity. The hepatic portal vein is a network of veins that carry blood from the gastrointestinal tract and spleen to the liver Fats, primarily in the form of triglycerides, are absorbed in the intestines and transported through the lymphatic system as chylomicrons. GABA (gamma-aminobutyric acid) is the main inhibitory neurotransmitter in the central nervous system. It plays a crucial role in reducing neuronal excitability throughout the nervous system. (also gets released from beta islets sends down a signal binds to alpha islets shuts its down to stop glucagon) Blood from the stomach, intestines, pancreas, and spleen is collected via the hepatic portal vein and transported to the liver. There, the liver processes nutrients, stores glucose as glycogen, and detoxifies harmful substances before the blood is returned to the general circulation via the hepatic veins. Type 1 Diabetes Cause: An autoimmune response destroys insulin-producing beta cells in the pancreas. Onset: Typically develops in childhood or adolescence, but can occur at any age. Insulin: Individuals are insulin-dependent, requiring lifelong insulin therapy for survival. Symptoms: Sudden onset of symptoms such as excessive thirst, frequent urination, and weight loss. Management: Requires careful monitoring of blood glucose levels and insulin administration. Type 2 Diabetes  Cause: Primarily associated with insulin resistance, where the body’s cells do not respond effectively to insulin, often linked to lifestyle factors and genetics. Onset: More common in adults, but increasingly diagnosed in children and adolescents due to rising obesity rates. Insulin: Some individuals may eventually require insulin, but many can manage the condition with lifestyle changes and oral medications. Symptoms: Gradual onset; symptoms may be less obvious initially and include fatigue, blurred vision, and slow healing of wounds. Management: Focuses on lifestyle modifications (diet and exercise), monitoring bloo -The anterior pituitary, responsible for producing and secreting several key hormones that regulate various bodily functions. It is stimulated by releasing and inhibiting hormones from the hypothalamus. Key hormones produced by the anterior pituitary include: 1. Growth Hormone (GH): Stimulates growth and cell reproduction. 2. Prolactin (PRL): Promotes milk production in breastfeeding. 3. Adrenocorticotropic Hormone (ACTH): Stimulates the adrenal glands to produce cortisol. 4. Thyroid-Stimulating Hormone (TSH): Stimulates the thyroid gland to produce thyroid hormones. 5. Luteinizing Hormone (LH) and Follicle-Stimulating Hormone (FSH)  6. (FSH): Regulate reproductive processes in both males and females. -The posterior pituitary, or neurohypophysis, is the part of the pituitary gland that stores and releases hormones produced by the hypothalamus. It primarily releases two key hormones: 1. Oxytocin: Involved in childbirth and lactation, it stimulates uterine contractions during labor and promotes milk ejection during breastfeeding. It also plays a role in social bonding and emotional responses. 2. Antidiuretic Hormone (ADH), also known as vasopressin: Regulates water balance in the body by promoting water reabsorption in the kidneys, which helps control blood pressure and volume. -Negative Feedback Definition: A process that counteracts a change to bring the system back to its set point or normal state. Example: The regulation of blood glucose levels. When blood glucose rises, insulin is released to lower it. Conversely, when glucose levels drop, glucagon is released to increase them. Another example Body Temperature Regulation Function: Helps maintain stability by reversing deviations from a set point. -Positive Feedback Definition: A process that amplifies or increases a change in the system, pushing it further away from the starting point. Example: Childbirth. During labor, the release of oxytocin increases contractions, which leads to more oxytocin being released until delivery occurs. another example Fever  Function: Drives processes to completion, often in situations that need a definitive end point. Releasing hormones are hormones produced by the hypothalamus that stimulate the anterior pituitary gland to release its own hormones Growth Hormone-Releasing Hormone (GHRH): Stimulates the release of Growth Hormone (GH), promoting growth and metabolism. Prolactin-Releasing Hormone (PRH): Stimulates the release of Prolactin (PRL), which promotes milk production. The renin-angiotensin pathway, often referred to as the renin-angiotensin-aldosterone system (RAAS), is a critical hormonal system that regulates blood pressure, fluid balance, and electrolyte levels. Here’s an overview of the pathway: The adrenal glands are small, triangular-shaped glands located on top of each kidney. (santa hats) They play a crucial role in producing hormones that regulate various bodily functions. Each adrenal gland has two main parts: 1. Adrenal Cortex Outer Layer: Produces steroid hormones. Glucocorticoids (e.g., cortisol): Regulate metabolism, stress response, and immune function. Mineralocorticoids (e.g., aldosterone): Regulate sodium and potassium balance and control blood pressure. Androgens: Contribute to the development of secondary sexual characteristics. 2. Adrenal Medulla Inner Layer: Produces catecholamines. Epinephrine (adrenaline) and norepinephrine (noradrenaline): Involved in the “fight or flight” response, increasing heart rate, blood pressure, and energy availability. Functions The adrenal glands are vital for: Stress Response: Helping the body respond to stress through hormone release. Metabolism Regulation: Influencing how the body utilizes carbohydrates, fats, and proteins. Electrolyte Balance: Regulating sodium and potassium levels, thus affecting blood pressure. Dysfunction of the adrenal glands can lead to conditions like Addison’s disease (underproduction of hormones) or Cushing’s syndrome (overproduction of cortisol). 20 Question Test w/ answers and rationale 1. Which cells in the pancreas produce insulin? A) Alpha cells B) Beta cells C) Delta cells D) Gamma cells Answer: B Rationale: Beta cells produce insulin, which lowers blood glucose levels. 2. What is the primary function of alpha cells in the pancreas? A) Produce insulin B) Produce glucagon C) Produce somatostatin D) Produce cortisol Answer: B Rationale: Alpha cells produce glucagon, which increases blood glucose levels. 3. Delta cells in the pancreas produce which hormone? A) Insulin B) Glucagon C) Somatostatin D) Epinephrine Answer: C Rationale: Delta cells produce somatostatin, which regulates insulin and glucagon. 4. What is the main difference between endocrine and exocrine glands? A) Endocrine glands release secretions through ducts. B) Exocrine glands release hormones into the bloodstream. C) Endocrine glands release hormones directly into the bloodstream. D) Exocrine glands produce only enzymes. Answer: C Rationale: Endocrine glands release hormones directly into the bloodstream, while exocrine glands release secretions through ducts. 5. Which of the following best describes glycogen?  A) A long chain of proteins B) A chain of glucose molecules C) A collection of fats D) A sequence of amino acids Answer: B Rationale: Glycogen is made up of glucose units linked together and is stored for quick energy release. 6. What is the primary role of glucagon in the body? A) Lower blood glucose levels B) Increase glycogen synthesis C) Raise blood glucose levels D) Stimulate insulin production Answer: C Rationale: Glucagon raises blood glucose levels by promoting glycogen breakdown and gluconeogenesis in the liver. 7. What is the main role of insulin receptors on cells? A) To produce insulin B) To break down glucose C) To bind insulin for glucose regulation D) To produce glycogen Answer: C Rationale: Insulin receptors on cells bind to insulin, facilitating glucose uptake. 8. Which vein carries nutrient-rich blood from the GI tract to the liver? A) Hepatic portal vein  B) Renal vein C) Pulmonary vein D) Carotid vein Answer: A Rationale: The hepatic portal vein transports blood from the GI tract and spleen to the liver for processing. 9. Type 1 diabetes is primarily caused by: A) Insulin resistance B) Overproduction of glucagon C) Autoimmune destruction of beta cells D) Deficient glucagon production Answer: C Rationale: Type 1 diabetes occurs when an autoimmune response destroys insulin-producing beta cells in the pancreas. 10. Which hormone is involved in the fight-or-flight response? A) Insulin B) Cortisol C) Epinephrine D) Somatostatin Answer: C Rationale: Epinephrine, produced by the adrenal medulla, is released during the fight-or-flight response. Anterior and Posterior Pituitary Hormones: 11. Which hormone from the anterior pituitary stimulates milk production? A) Growth hormone  B) Prolactin C) Oxytocin D) ADH Answer: B Rationale: Prolactin promotes milk production in breastfeeding. 12. The hormone that stimulates the adrenal glands to produce cortisol is: A) TSH B) LH C) ACTH D) FSH Answer: C Rationale: ACTH stimulates the adrenal cortex to produce cortisol. 13. What is the primary role of ADH (antidiuretic hormone)? A) Promote milk ejection B) Regulate water balance C) Stimulate uterine contractions D) Increase heart rate Answer: B Rationale: ADH, released from the posterior pituitary, regulates water reabsorption in the kidneys. 14. Which hormone increases uterine contractions during childbirth? A) Prolactin B) Cortisol C) Oxytocin D) Insulin  Answer: C Rationale: Oxytocin promotes uterine contractions during labor. 15. Growth hormone-releasing hormone (GHRH) stimulates the release of: A) Prolactin B) ACTH C) Growth hormone D) LH Answer: C Rationale: GHRH from the hypothalamus stimulates the anterior pituitary to release growth hormone. Feedback Mechanisms: 16. Which process is an example of negative feedback? A) Childbirth B) Fever C) Blood glucose regulation D) Blood clotting Answer: C Rationale: Negative feedback helps maintain stability by counteracting deviations, as seen in blood glucose regulation. 17. Childbirth is an example of: A) Negative feedback B) Positive feedback C) Neutral feedback D) No feedback Answer: B Rationale: Positive feedback amplifies a process to completion, as in childbirth. Adrenal Glands: 18. Which hormone from the adrenal cortex helps regulate sodium and potassium? A) Cortisol B) Epinephrine C) Aldosterone D) Norepinephrine Answer: C Rationale: Aldosterone, a mineralocorticoid, helps regulate sodium and potassium balance. 19. The adrenal medulla primarily releases: A) Cortisol and aldosterone B) Epinephrine and norepinephrine C) Androgens and estrogens D) Glucagon and insulin Answer: B Rationale: The adrenal medulla produces epinephrine and norepinephrine for the fight-or-flight response. 20. The main inhibitory neurotransmitter in the central nervous system is: A) GABA B) Glutamate C) Dopamine D) Serotonin  Answer: A Rationale: GABA is the primary inhibitory neurotransmitter, reducing neuronal excitability. Chapter 18 Component of Blood Plasma, Buffy Coat, Blood Cells 1. Plasma Description: The liquid portion of blood, making up about 55% of its volume. Components: Water (about 90%) Proteins (such as albumin, globulins, and fibrinogen) Electrolytes (sodium, potassium, calcium, etc.) Nutrients (glucose, amino acids, lipids) Hormones and waste products (urea, creatinine) 2. Blood Cells Red Blood Cells (Erythrocytes): Function: Carry oxygen from the lungs to the body and carbon dioxide from the body back to the lungs. Contains hemoglobin, a protein that binds oxygen. White Blood Cells (Leukocytes): Function: Part of the immune system, helping to fight infections.  Types include neutrophils, lymphocytes, monocytes, eosinophils, and basophils. Platelets (Thrombocytes): Function: Play a crucial role in blood clotting and wound healing. Each hemoglobin molecule contains four heme (2 alpha 2 beta ) groups. ( has iron on then them bind to oxygen )Each heme group can bind one molecule of oxygen, allowing a single hemoglobin molecule to carry up to four oxygen molecules in total. 5% of carbon dioxide is carried in the heme groups 1. ABO Blood Group System Type A: Has A antigens on the surface of red blood cells and anti-B antibodies in the plasma. Type B: Has B antigens and anti-A antibodies. Type AB: Has both A and B antigens, with no anti-A or anti-B antibodies (universal recipient). Type O: Has no A or B antigens and both anti-A and anti-B antibodies (universal donor o-). 2. Rh Factor Rh-positive (Rh+): Has the Rh antigen (D antigen) on the red blood cells. Rh-negative (Rh-): Lacks the Rh antigen. *blood donation rule if i don’t have it i don’t want it * Agglutination is the clumping of cells, such as red blood cells or bacteria, caused by the binding of antibodies to specific antigens on the surface of those cells. This process can occur in various contexts, such as blood typing, immune responses, and infections. Key Points: Mechanism: When antibodies (which are proteins produced by the immune system) encounter their specific antigens, they bind to them. This binding causes the cells to stick together, leading to visible clumps. Clinical Significance: Blood Typing: Agglutination tests are used to determine blood types. For example, if anti-A antibodies are mixed with type A blood, agglutination occurs, confirming the presence of A antigens. Antibodies have a Y-shaped structure with variable regions that bind to specific antigens. This allows them to identify and neutralize specific pathogens. Agglutinins Agglutinins are antibodies that cause agglutination. They can specifically bind to antigens on the surfaces of cells, leading to the clumping effect. Antigen Any substance that can provoke an immune response in the body. Antigens are typically found on the surface of pathogens, such as bacteria and viruses, but they can also be present on the surface of cells, including red blood cells. Erythropoietin (EPO) is a hormone produced primarily by the kidneys that stimulates the production of red blood cells (erythropoiesis) in the bone marrow. Here are some key points about EPO: Functions: Stimulates Red Blood Cell Production: EPO increases the number of red blood cells, enhancing the blood’s ability to carry oxygen.  Regulates Oxygen Levels: It is released in response to low oxygen levels (hypoxia) in the blood, ensuring sufficient red blood cell production to meet the body’s oxygen demands. 20 Question Test w/ answers and rationale 1. What percentage of blood volume is composed of plasma? A) 10% B) 25% C) 55% D) 75% Answer: C Rationale: Plasma constitutes about 55% of the total blood volume. 2. What is the primary component of plasma? A) Proteins B) Water C) Electrolytes D) Hormones Answer: B Rationale: Plasma is primarily composed of about 90% water. 3. Which of the following proteins is essential for blood clotting? A) Albumin B) Globulin C) Fibrinogen D) Hemoglobin Answer: C Rationale: Fibrinogen is a crucial protein in the coagulation process. 4. The primary function of red blood cells (erythrocytes) is to:  A) Fight infections B) Carry oxygen C) Clot blood D) Produce antibodies Answer: B Rationale: Red blood cells transport oxygen from the lungs to tissues and carbon dioxide back to the lungs. 5. What is the role of white blood cells (leukocytes)? A) Carry oxygen B) Transport nutrients C) Fight infections D) Maintain blood pressure Answer: C Rationale: White blood cells are crucial components of the immune system, protecting the body against infections. 6. What is the function of platelets (thrombocytes)? A) Oxygen transport B) Immune response C) Blood clotting D) Nutrient transport Answer: C Rationale: Platelets are essential for the blood clotting process. 7. Each hemoglobin molecule can bind a maximum of how many oxygen molecules? A) 2 B) 4 C) 6 D) 8 Answer: B Rationale: Hemoglobin can bind up to four oxygen molecules, one for each heme group. 8. What percentage of carbon dioxide is carried by hemoglobin in the heme groups? A) 5% B) 10% C) 25% D) 50% Answer: A Rationale: Hemoglobin carries about 5% of carbon dioxide in the heme groups. ABO Blood Group System: 9. Which blood type has A antigens on the surface of red blood cells? A) Type A B) Type B C) Type AB D) Type O Answer: A Rationale: Type A blood has A antigens on the surface of red blood cells. 10. What is unique about Type AB blood? A) It has both A and B antigens B) It has no antigens C) It has only A antigens D) It has only B antigens Answer: A Rationale: Type AB blood has both A and B antigens, making it the universal recipient.  11. Which blood type is known as the universal donor? A) Type A B) Type B C) Type AB D) Type O Answer: D Rationale: Type O blood has no A or B antigens, allowing it to be given to any blood type without causing an immune reaction. 12. A person with Type B blood has which antibodies in their plasma? A) Anti-A antibodies B) Anti-B antibodies C) Both anti-A and anti-B antibodies D) No antibodies Answer: A Rationale: Type B blood contains anti-A antibodies. Rh Factor: 13. What does it mean if a person is Rh-positive (Rh+)? A) They lack the Rh antigen B) They have the Rh antigen C) They have only A antigens D) They have both A and B antigens Answer: B Rationale: Rh-positive individuals have the Rh antigen (D antigen) present on their red blood cells. 14. Which of the following blood types can a Rh-negative individual receive? A) Rh-positive only  B) Rh-negative only C) Any blood type D) Rh-positive and Rh-negative Answer: D Rationale: Rh-negative individuals can safely receive Rh-negative blood but may have complications if they receive Rh-positive blood. 15. What is the main consequence of agglutination? A) Increased oxygen transport B) Clumping of cells C) Enhanced immune response D) Decreased blood volume Answer: B Rationale: Agglutination refers to the clumping of cells, typically red blood cells, caused by antibody binding to antigens. 16. Agglutination tests are primarily used in which context? A) Diagnosing infections B) Blood typing C) Measuring blood pressure D) Assessing kidney function Answer: B Rationale: Agglutination tests help determine blood types by checking for specific antigen-antibody reactions. Erythropoietin (EPO): 17. What is the primary function of erythropoietin (EPO)? A) Increase platelet production B) Stimulate red blood cell production C) Regulate blood pressure  D) Promote white blood cell function Answer: B Rationale: EPO is a hormone that stimulates the production of red blood cells in response to low oxygen levels. 18. Where is erythropoietin primarily produced? A) Liver B) Heart C) Kidneys D) Bone marrow Answer: C Rationale: Erythropoietin is primarily produced by the kidneys. 19. Erythropoietin is released in response to which condition? A) High blood pressure B) Low oxygen levels (hypoxia) C) High blood sugar levels D) Dehydration Answer: B Rationale: EPO is released when oxygen levels in the blood are low to stimulate red blood cell production. General Knowledge: 20. What is the primary role of antibodies? A) Carry oxygen B) Bind to specific antigens C) Regulate blood pressure D) Produce energy Answer: B Rationale: Antibodies bind to specific antigens, marking pathogens for destruction and neutralizing them. Chapter 19 and 20 Arteries take blood away from the heart veins take blood to the heart Chambers of the heart 1. Right Atrium Function: Receives deoxygenated blood from the body via the superior and inferior vena cavae. Role: Blood flows from the right atrium into the right ventricle through the tricuspid valve. 2. Right Ventricle Function: Pumps deoxygenated blood to the lungs through the pulmonary artery for oxygenation. Role: Blood moves from the right ventricle to the lungs via the pulmonary valve. 3. Left Atrium Function: Receives oxygenated blood from the lungs via the pulmonary veins. Role: Blood flows from the left atrium into the left ventricle through the mitral valve. 4. Left Ventricle Function: Pumps oxygenated blood to the rest of the body through the aorta. Role: Blood is expelled from the left ventricle through the aortic valve. Valves of the heart 1. Tricuspid Valve Location: Between the right atrium and right ventricle. Function: Prevents backflow of blood into the right atrium when the right ventricle contracts. 2. Pulmonary Semi Lunar Valve Location: Between the right ventricle and the pulmonary artery. Function: Prevents backflow of blood into the right ventricle after it has been pumped into the pulmonary artery to the lungs. 3. Mitral Valve (Bicuspid Valve) Location: Between the left atrium and left ventricle. Function: Prevents backflow of blood into the left atrium when the left ventricle contracts. 4. Aortic Semi Lunar Valve Location: Between the left ventricle and the aorta. Function: Prevents backflow of blood into the left ventricle after it has been pumped into the aorta to supply the body with oxygenated blood. Deoxygenated Parts of the Heart 1. Right Atrium: Receives deoxygenated blood from the body through the superior and inferior vena cavae. 2. Right Ventricle:  Pumps deoxygenated blood to the lungs via the pulmonary artery for oxygenation. Oxygenated Parts of the Heart 1. Left Atrium: Receives oxygenated blood from the lungs through the pulmonary veins. 2. Left Ventricle: Pumps oxygenated blood to the rest of the body through the aorta. 1. Deoxygenated Blood Returns to the Heart From the Body: Deoxygenated blood returns via the superior and inferior vena cavae into the right atrium. 2. Right Atrium to Right Ventricle Blood flows from the right atrium through the tricuspid valve into the right ventricle. 3. Right Ventricle to Lungs The right ventricle contracts, sending blood through the pulmonary valve into the pulmonary arteries, which carry it to the lungs for oxygenation. 4. Oxygenated Blood Returns to the Heart After picking up oxygen, the oxygenated blood returns via the pulmonary veins into the left atrium. 5. Left Atrium to Left Ventricle  Blood flows from the left atrium through the mitral (bicuspid) valve into the left ventricle. 6. Left Ventricle to the Body The left ventricle contracts, sending blood through the aortic valve into the aorta, which distributes oxygenated blood to the rest of the body. Pressure gradients are fundamental to the functioning of the cardiovascular system, Blood flows from areas of higher pressure (like the left ventricle) to areas of lower pressure (like the systemic arteries and capillaries). This gradient ensures continuous blood flow to supply tissues with oxygen and nutrients.. Systolic Pressure: This is the higher number in a blood pressure reading (e.g., in 120/80 mmHg, 120 is the systolic pressure). It measures the pressure in the arteries when the heart’s ventricles contract and pump blood out into the arteries. Systolic pressure reflects the force of the heart’s contraction and is influenced by factors such as the strength of the heartbeat, the elasticity of the artery walls, and the volume of blood in the arteries. Diastolic Pressure: This is the lower number in a blood pressure reading (e.g., in 120/80 mmHg, 80 is the diastolic pressure). It measures the pressure in the arteries when the heart is relaxed between beats, specifically during the diastole phase, when the ventricles refill with blood. Diastolic pressure reflects the baseline pressure within the arteries and can indicate artery health and elasticity. 1. Lubb (S1) Sound: The first heart sound (S1), often described as “lubb.”  Cause: Occurs when the atrioventricular (AV) valves (the mitral and tricuspid valves) close at the beginning of ventricular contraction (systole). Timing: Marks the onset of ventricular systole. 2. Dupp (S2) Sound: The second heart sound (S2), often described as “dupp.” Cause: Occurs when the semilunar valves (the aortic and pulmonary valves) close at the end of ventricular contraction. Timing: Marks the beginning of ventricular diastole. Cardiac output (CO) is the volume of blood the heart pumps per minute and is a crucial measure of cardiovascular function. It is determined by two main factors: 1. Heart Rate (HR) The number of times the heart beats per minute. 2. Stroke Volume (SV) The amount of blood ejected by the left ventricle with each heartbeat. Formula The formula for calculating cardiac output is: CO= HR x SV Pectinate muscles are thin, comb-like muscular ridges found in the atria of the heart, particularly in the right atrium.Pectinate muscles help in the contraction of the atria, allowing for more effective pumping of blood into the ventricles. Tubercles cordinae, also known as chordae tendineae, are fibrous cords in the heart that connect the papillary muscles to the atrioventricular (AV) valves (the tricuspid and mitral valves. They anchor the AV valves to the papillary muscles, which are located within the ventricles. Papillary muscles are small, conical muscles located in the ventricles of the heart. During ventricular contraction (systole), the papillary muscles contract, pulling on the chordae tendineae. This action prevents the AV valves from inverting or prolapsing into the atria, ensuring they remain closed and blood flows correctly from the ventricles to the arteries The sinoatrial (SA) node and atrioventricular (AV) node are critical components of the heart’s electrical conduction system, responsible for regulating the heartbeat. Sinoatrial (SA) Node Location: Located in the right atrium, near the opening of the superior vena cava. Function: Acts as the primary pacemaker of the heart, generating electrical impulses that initiate each heartbeat. This causes the atria to contract and push blood into the ventricles. Rate: The SA node typically fires at a rate of 60 to 100 beats per minute, setting the pace for the heart under normal conditions. Atrioventricular (AV) Node Location: Situated at the junction of the atria and ventricles, near the interatrial septum. Function: Receives electrical impulses from the SA node and delays them slightly before passing them to the ventricles. This delay allows the atria to fully contract and empty blood into the ventricles before the ventricles contract. Rate: The AV node can act as a secondary pacemaker if the SA node fails, typically firing at a rate of 40 to 60 beats per minute. Phases of Cardiac Action Potential 1. Phase 0 (Depolarization): Cause: Rapid influx of sodium ions (Na+) through voltage-gated sodium channels. Effect: The membrane potential becomes more positive, leading to depolarization. 2. Phase 1 (Initial Repolarization): Cause: Inactivation of sodium channels and a brief efflux of potassium ions (K+) through transient outward potassium channels. Effect: Membrane potential begins to decrease slightly. 3. Phase 2 (Plateau Phase): Cause: Opening of calcium channels (L-type calcium channels) allows calcium ions (Ca²+) to enter the cell while potassium channels remain open. Effect: This balance of calcium influx and potassium efflux leads to a plateau, which prolongs depolarization and allows for a sustained contraction. 4. Phase 3 (Repolarization): Cause: Closure of calcium channels and continued efflux of potassium ions through delayed rectifier potassium channels. Effect: The membrane potential returns to a more negative value, leading to repolarization.  5. Phase 4 (Resting Potential): State: The cell is at rest, typically around -90 mV, maintained by the sodium-potassium pump and other ion channels. Preparation: The cell is ready to initiate another action potential. Regulatory proteins in muscle contraction, particularly in cardiac and skeletal muscles, play crucial roles in controlling the contraction process. 1. Troponin Structure: A complex of three proteins (troponin C, troponin I, and troponin T). Function: Troponin C: Binds calcium ions, initiating the contraction process. Troponin I: Inhibits actin-myosin interaction when calcium levels are low. Troponin T: Anchors the troponin complex to tropomyosin. 2. Tropomyosin Structure: A long, thin protein that wraps around actin filaments. Function: Blocks myosin-binding sites on actin in a relaxed muscle, preventing contraction. When calcium binds to troponin, tropomyosin shifts, exposing the binding sites for myosin. 3. Myosin  Structure: Thick filament protein with a head that can bind to actin. Function: Converts chemical energy (ATP) into mechanical energy during contraction. Myosin heads bind to actin, forming cross-bridges that pull the filaments past each other, resulting in muscle contraction. 1. P Wave Description: Represents atrial depolarization. Event: This is the electrical impulse that causes the atria to contract, pushing blood into the ventricles. Duration: Usually lasts about 0.08 to 0.1 seconds. 2. QRS Complex Description: Represents ventricular depolarization. Event: This is when the electrical impulse spreads through the ventricles, causing them to contract and pump blood to the lungs and the rest of the body. The QRS complex is typically much larger than the P wave because the ventricles are more muscular than the atria. Duration: Usually lasts about 0.06 to 0.1 seconds. 3. T Wave Description: Represents ventricular repolarization. Event: This is when the ventricles recover from contraction and reset their electrical state in preparation for the next heartbeat. Duration: Varies but generally lasts about 0.1 to 0.3 seconds. High blood pressure, also known as hypertension, is a common condition where the force of the blood against the walls of the arteries is consistently too high. Here are key points about hypertension: Classification Normal: Less than 120/80 mm Hg Elevated: 120-129/less than 80 mm Hg Hypertension Stage 1: 130-139/80-89 mm Hg Hypertension Stage 2: 140 or higher/90 or higher mm Hg Hypertensive Crisis: Higher than 180/higher than 120 mm Hg (requires immediate medical attention) 20 Question Test w/ answers and rationale 1. Which chamber of the heart receives deoxygenated blood from the body? A) Left Ventricle B) Right Ventricle C) Right Atrium D) Left Atrium Answer: C) Right Atrium Rationale: The right atrium receives deoxygenated blood from the body via the superior and inferior vena cavae. 2. What is the function of the pulmonary semi-lunar valve? A) Prevents backflow of blood into the left atrium B) Prevents backflow of blood into the right ventricle C) Prevents backflow of blood into the aorta D) Prevents backflow of blood into the pulmonary veins Answer: B) Prevents backflow of blood into the right ventricle Rationale: The pulmonary semi-lunar valve prevents blood from flowing back into the right ventricle after it has been pumped into the pulmonary artery. 3. Which valve prevents backflow of blood into the left ventricle? A) Tricuspid Valve B) Aortic Semi-Lunar Valve C) Pulmonary Semi-Lunar Valve D) Mitral Valve Answer: B) Aortic Semi-Lunar Valve Rationale: The aortic semi-lunar valve prevents backflow of blood into the left ventricle after it is pumped into the aorta. 4. Where does oxygenated blood return to the heart? A) From the body via the vena cavae B) From the lungs via the pulmonary veins C) From the aorta D) From the right ventricle Answer: B) From the lungs via the pulmonary veins Rationale: Oxygenated blood returns to the heart through the pulmonary veins into the left atrium. 5. Which of the following is the primary pacemaker of the heart? A) Atrioventricular (AV) Node B) Sinoatrial (SA) Node C) Bundle of His D) Purkinje Fibers Answer: B) Sinoatrial (SA) Node Rationale: The SA node, located in the right atrium, generates electrical impulses that initiate each heartbeat. 6. What structure prevents the AV valves from inverting during ventricular contraction? A) Chordae Tendineae B) Pectinate Muscles C) Papillary Muscles D) Sinoatrial Node Answer: C) Papillary Muscles Rationale: Papillary muscles contract during ventricular contraction to pull on the chordae tendineae, preventing the AV valves from inverting. 7. What happens during the ‘lubb’ sound of the heartbeat? A) Closure of the semilunar valves B) Closure of the AV valves C) Atrial contraction D) Ventricular contraction Answer: B) Closure of the AV valves Rationale: The ‘lubb’ (S1) sound occurs when the mitral and tricuspid valves close at the beginning of ventricular contraction. 8. What is the primary function of the left ventricle? A) Pump deoxygenated blood to the lungs B) Pump oxygenated blood to the body C) Receive oxygenated blood from the lungs D) Receive deoxygenated blood from the body Answer: B) Pump oxygenated blood to the body Rationale: The left ventricle pumps oxygenated blood to the rest of the body through the aorta. 9. Which phase of the cardiac action potential is characterized by rapid influx of sodium ions? A) Phase 1 B) Phase 2 C) Phase 0 D) Phase 3 Answer: C) Phase 0 Rationale: Phase 0 is marked by depolarization due to the rapid influx of sodium ions. 10. The pressure in the arteries when the heart is relaxed is known as: A) Systolic Pressure B) Diastolic Pressure C) Pulse Pressure D) Mean Arterial Pressure Answer: B) Diastolic Pressure Rationale: Diastolic pressure measures the pressure in the arteries when the heart is relaxed between beats. 11. What structure is responsible for the electrical delay between the atria and ventricles? A) Bundle of His B) Purkinje Fibers C) Atrioventricular (AV) Node D) Sinoatrial (SA) Node Answer: C) Atrioventricular (AV) Node Rationale: The AV node receives impulses from the SA node and delays them slightly to allow for complete atrial contraction before ventricular contraction. 12. Which of the following best describes stroke volume (SV)? A) The amount of blood pumped by the heart per minute B) The volume of blood ejected by the left ventricle with each heartbeat C) The volume of blood in the heart at rest D) The pressure of blood in the arteries Answer: B) The volume of blood ejected by the left ventricle with each heartbeat Rationale: Stroke volume refers specifically to the amount of blood the left ventricle pumps out with each contraction. 13. What is the normal range for systolic blood pressure? A) Less than 80 mm Hg B) 90-120 mm Hg C) 120-130 mm Hg D) Less than 120 mm Hg Answer: D) Less than 120 mm Hg Rationale: Normal systolic blood pressure is considered to be less than 120 mm Hg. 14. Which wave in an electrocardiogram (ECG) represents ventricular repolarization? A) P Wave B) QRS Complex C) T Wave D) U Wave Answer: C) T Wave Rationale: The T wave represents the repolarization of the ventricles after contraction. 15. Which part of the heart receives deoxygenated blood from the pulmonary artery? A) Right Atrium B) Left Atrium C) Right Ventricle D) Left Ventricle Answer: C) Right Ventricle Rationale: The right ventricle pumps deoxygenated blood to the lungs via the pulmonary artery for oxygenation. 16. How does blood flow through the heart? A) Right atrium → Left ventricle → Aorta B) Left atrium → Right ventricle → Pulmonary artery C) Right atrium → Right ventricle → Pulmonary artery D) Left ventricle → Right atrium → Pulmonary veins Answer: C) Right atrium → Right ventricle → Pulmonary artery Rationale: Blood flows from the right atrium to the right ventricle and then to the lungs via the pulmonary artery. 17. What are the comb-like muscular ridges found in the atria called? A) Papillary Muscles B) Chordae Tendineae C) Pectinate Muscles D) Interventricular Septum Answer: C) Pectinate Muscles Rationale: Pectinate muscles are muscular ridges found in the atria that aid in contraction. 18. Which term refers to the backflow of blood into the heart chambers? A) Hypertension B) Regurgitation C) Thrombosis D) Embolism Answer: B) Regurgitation Rationale: Regurgitation is the backflow of blood into the heart chambers, often due to valve incompetence. 19. What role do chordae tendineae play in the heart? A) Connect the aorta to the heart B) Anchor the valves to the papillary muscles C) Conduct electrical impulses D) Pump blood from the heart Answer: B) Anchor the valves to the papillary muscles Rationale: Chordae tendineae are fibrous cords that connect the AV valves to the papillary muscles to prevent inversion. 20. What is cardiac output (CO)? A) The volume of blood pumped by the heart in one contraction B) The volume of blood the heart pumps per minute C) The pressure in the arteries during contraction D) The amount of oxygen carried by the blood Answer: B) The volume of blood the heart pumps per minute Rationale: Cardiac output is calculated by multiplying heart rate by stroke volume, representing the total volume of blood pumped by the heart each minute. Chapter 21 Chapter 21 Key Functions of the Lymphatic System 1. Fluid Balance: Maintains the body’s fluid balance by collecting excess interstitial fluid and returning it to the bloodstream. 2. Immune Function: Transports lymph, which contains lymphocytes (white blood cells), helping to defend against pathogens.  3. Fat Absorption: Absorbs fats and fat-soluble vitamins from the digestive system through specialized lymphatic vessels 85% of Fluid Returned: Approximately 85% of the interstitial fluid (the fluid that surrounds cells) is reabsorbed into the blood capillaries. 15% of Fluid Drained: The remaining 15% of interstitial fluid is collected by the lymphatic system and returned to the circulatory system. Together, T cells and B cells form a critical part of the adaptive immune system, working in concert to identify, target, and eliminate pathogens while also providing long-term immunity through memory cells. Types of Tonsils 1. Palatine Tonsils: Located on either side of the back of the throat. The most commonly referred to when talking about tonsils. 2. Pharyngeal Tonsil (Adenoid): Located in the roof of the nasopharynx (behind the nose). Often referred to as adenoids when enlarged. 3. Lingual Tonsils: Located at the base of the tongue. The thymus is a small, glandular organ located in the upper chest, behind the sternum. It plays a crucial role in the immune system, particularly in the development of T cells (a type of white blood cell). Location: Situated in the mediastinum, between the lungs, and extends from the neck down to the heart. Size: The thymus is largest in childhood and gradually shrinks with age, becoming less active in adults. White blood cells (WBCs), or leukocytes, are crucial components of the immune system, responsible for protecting the body against infections and foreign invaders. Types of White Blood Cells 1. Neutrophils: Most abundant WBCs, making up 50-70% of all leukocytes. Primary defenders against bacterial infections; they engulf and destroy pathogens. 2. Lymphocytes: Comprising about 20-40% of WBCs. B cells: Produce antibodies and are key in humoral immunity. NK cells are part of the innate immune system and are classified under lymphocytes, along with T cells and B cells. T cells: Involved in cell-mediated immunity; they help destroy infected or cancerous cells. 3. Monocytes: Account for 2-8% of WBCs. They differentiate into macrophages and dendritic cells when they migrate into tissues, where they help engulf pathogens and present antigens to T cells. 4. Eosinophils: Make up 1-4% of WBCs.  Play a role in combating parasitic infections and are involved in allergic reactions. 5. Basophils: Least common type, representing less than 1% of WBCs. Release histamine and heparin other chemicals during allergic responses and inflammatory reactions. Autoimmune diseases are conditions in which the immune system mistakenly attacks the body’s own tissues, perceiving them as foreign invaders Interferons are a group of signaling proteins produced by the body in response to viral infections and other immune challenges. They play a crucial role in the immune response by helping to regulate the activity of the immune system. Macrophages are essential components of the immune system, with diverse functions that include pathogen clearance, immune regulation, and tissue repair. Their ability to adapt to different roles makes them crucial for maintaining health and responding to infections. Antibodies, also known as immunoglobulins, are proteins produced by the immune system that specifically recognize and bind to foreign substances (antigens) such as pathogens, toxins, and viruses. Innate immunity is the body’s first line of defense against pathogens. It is a non-specific response that acts quickly to prevent infection. Born with it Adaptive immunity is a specific immune response that develops over time, tailored to recognize and eliminate specific pathogens. It involves memory, allowing for a quicker response upon subsequent exposures. Adapts over time Cellular Components: T Lymphocytes (T Cells):  Helper T Cells (CD4+): Activate B cells and cytotoxic T cells, enhancing the immune response. Cytotoxic T Cells (CD8+): Destroy infected or cancerous cells. B Lymphocytes (B Cells): Produce antibodies that specifically target antigens. Humoral and Cell-Mediated Immunity: Humoral Immunity: Mediated by antibodies produced by B cells. Cell-Mediated Immunity: Involves T cells targeting infected or abnormal cells. Memory: Creates memory cells that allow for a faster and stronger response upon re-exposure to the same pathogen. last decades Types of Antibodies 1. IgG: Most abundant in serum; provides long-term immunity and can cross the placenta. 2. IgA: Found in mucosal areas and secretions (saliva, tears, breast milk); plays a crucial role in mucosal immunity. 3. IgM: The first antibody produced in response to an infection; effective in forming complexes and activating the complement system.  4. IgE: Involved in allergic reactions and responses to parasitic infections; binds to allergens and triggers histamine release. 5. IgD: Primarily found on the surface of B cells; plays a role in B cell activation 20 Question Test w/ answers and rationale 1. What is one of the primary functions of the lymphatic system? A) Producing red blood cells B) Maintaining fluid balance C) Storing fat D) Regulating body temperature Answer: B) Maintaining fluid balance Rationale: The lymphatic system collects excess interstitial fluid and returns it to the bloodstream, helping to maintain fluid balance in the body. 2. Which component of the immune system is primarily responsible for the production of antibodies? A) Neutrophils B) T cells C) B cells D) Monocytes Answer: C) B cells Rationale: B cells are responsible for producing antibodies that target specific antigens. 3. Which type of tonsil is commonly referred to as adenoids when enlarged? A) Palatine tonsils B) Lingual tonsils C) Pharyngeal tonsil D) Nasopharyngeal tonsils Answer: C) Pharyngeal tonsil Rationale: The pharyngeal tonsil, when enlarged, is often referred to as adenoids. 4. What role does the thymus play in the immune system? A) Produces antibodies B) Develops T cells C) Filters lymph D) Absorbs fats Answer: B) Develops T cells Rationale: The thymus is crucial for the maturation of T cells, which are essential for the adaptive immune response. 5. Which white blood cells are primarily involved in the defense against bacterial infections? A) Lymphocytes B) Eosinophils C) Neutrophils D) Basophils Answer: C) Neutrophils Rationale: Neutrophils are the most abundant white blood cells and act as the primary defenders against bacterial infections. 6. What percentage of white blood cells are lymphocytes? A) 1-4% B) 20-40% C) 50-70% D) 2-8% Answer: B) 20-40% Rationale: Lymphocytes account for about 20-40% of all white blood cells. 7. Which type of white blood cell is least abundant in the bloodstream? A) Monocytes B) Eosinophils C) Basophils D) Neutrophils Answer: C) Basophils Rationale: Basophils are the least common type of white blood cells, representing less than 1% of the total leukocyte count. 8. What condition is characterized by the immune system mistakenly attacking the body’s own tissues? A) Allergies B) Autoimmune diseases C) Viral infections D) Bacterial infections Answer: B) Autoimmune diseases Rationale: Autoimmune diseases occur when the immune system targets and attacks the body’s own cells, mistaking them for foreign invaders. 9. Interferons are produced in response to what kind of challenges? A) Bacterial infections only B) Allergic reactions C) Viral infections and immune challenges D) Tissue injuries Answer: C) Viral infections and immune challenges Rationale: Interferons are signaling proteins produced in response to viral infections and other immune challenges, helping to regulate immune activity. 10. Which type of immunity is considered the body’s first line of defense? A) Adaptive immunity B) Innate immunity C) Humoral immunity D) Cell-mediated immunity Answer: B) Innate immunity Rationale: Innate immunity is the body’s first line of defense, providing a non-specific response to pathogens. 11. Which of the following is a characteristic of adaptive immunity? A) It is present at birth. B) It responds quickly to all pathogens. C) It develops over time and involves memory. D) It involves only physical barriers. Answer: C) It develops over time and involves memory. Rationale: Adaptive immunity is specific and develops after exposure to particular pathogens, allowing for a faster response during subsequent exposures. 12. What is the function of helper T cells? A) Destroy infected cells B) Activate B cells and cytotoxic T cells C) Produce antibodies D) Migrate to tissues Answer: B) Activate B cells and cytotoxic T cells Rationale: Helper T cells enhance the immune response by activating other immune cells, including B cells and cytotoxic T cells. 13. Which antibody is the most abundant in serum? A) IgE B) IgA C) IgG D) IgM Answer: C) IgG Rationale: IgG is the most abundant antibody in serum and provides long-term immunity. 14. What is the role of eosinophils in the immune system? A) Defense against bacterial infections B) Involvement in allergic reactions and combating parasitic infections C) Antibody production D) Activation of T cells Answer: B) Involvement in allergic reactions and combating parasitic infections Rationale: Eosinophils are involved in allergic responses and play a role in fighting parasitic infections. 15. Which of the following is a component of humoral immunity? A) Cytotoxic T cells B) Helper T cells C) Antibodies D) Macrophages Answer: C) Antibodies Rationale: Humoral immunity is mediated by antibodies produced by B cells that target specific antigens. 16. What are macrophages primarily responsible for? A) Producing antibodies B) Differentiating into memory cells C) Pathogen clearance and immune regulation D) Activating B cells Answer: C) Pathogen clearance and immune regulation Rationale: Macrophages play a vital role in clearing pathogens, regulating the immune response, and facilitating tissue repair. 17. The primary function of antibodies is to: A) Recognize and bind to antigens B) Activate T cells C) Produce hormones D) Generate inflammation Answer: A) Recognize and bind to antigens Rationale: Antibodies specifically recognize and bind to foreign substances (antigens) to help eliminate them. 18. What is the role of the lymphatic vessels in fat absorption? A) Absorb excess interstitial fluid B) Transport red blood cells C) Absorb fats and fat-soluble vitamins D) Filter blood Answer: C) Absorb fats and fat-soluble vitamins Rationale: Specialized lymphatic vessels called lacteals absorb fats and fat-soluble vitamins from the digestive system. 19. What characterizes the difference between adaptive and innate immunity? A) Adaptive immunity is faster than innate immunity. B) Innate immunity is specific, while adaptive immunity is non-specific. C) Adaptive immunity involves memory and specificity. D) Innate immunity has a longer duration than adaptive immunity. Answer: C) Adaptive immunity involves memory and specificity. Rationale: Adaptive immunity is characterized by its ability to remember past infections and provide a specific response, unlike the non-specific innate immunity. 20. What type of immunity involves the action of T lymphocytes? A) Humoral immunity B) Passive immunity C) Cell-mediated immunity D) Innate immunity Answer: C) Cell-mediated immunity Rationale: Cell-mediated immunity involves T lymphocytes targeting and destroying infected or abnormal cells. Chapter 22 Bicarbonate pathway involves bicarbonate ions (HCO₃⁻) helping to regulate the body’s pH balance.  1. Carbon Dioxide (CO₂): Produced during cellular respiration and can combine with water to form carbonic acid. 2. Carbonic Acid (H₂CO₃): Formed from the reaction between CO₂ and water. This is a weak acid that can dissociate into bicarbonate ions and hydrogen ions. 3. Bicarbonate Ion (HCO₃⁻): Acts as a base and can accept hydrogen ions, helping to neutralize acids and raise pH. 4. Hydrogen Ion (H⁺): An increase in hydrogen ions lowers pH, making the solution more acidic. - Buffer System: Bicarbonate acts as a buffer, neutralizing excess acids or bases in the blood. -Formation: It is formed from carbon dioxide (CO₂) and water through a reaction facilitated by an enzyme called carbonic anhydrase. - Transport: Bicarbonate helps transport CO₂ from tissues to the lungs for exhalation. -Regulation: The kidneys control bicarbonate levels by reabsorbing it or excreting hydrogen ions (H⁺), affecting overall pH. Too much hydrogen in leads to acidosis Too much hydrogen out leads to alkalosis Acidosis-blood pH lower than 7.35 Alkalosis-blood pH higher than 7.45 Neutral 7.35-7.45 Pharynx Description:  The pharynx is a muscular tube that connects the nasal cavity and mouth to the esophagus and larynx. It is about 5 inches long and can be divided into three main regions: 1. Nasopharynx: Located behind the nasal cavity, it is primarily involved in the respiratory function. It contains the pharyngeal tonsils (adenoids) that help trap pathogens. 2. Oropharynx: Located behind the oral cavity, it serves both respiratory and digestive functions. It is the passage for air and food. 3. Laryngopharynx: The lowest part that connects the oropharynx to the larynx and esophagus. It directs food to the esophagus and air to the larynx. Functions: Air Passage: Allows the passage of air from the nasal cavity to the larynx and then to the trachea. Food Passage: Acts as a pathway for food from the mouth to the esophagus. Resonance Chamber: Contributes to the resonance of speech sounds. Larynx Description: The larynx, commonly known as the voice box, is a cartilaginous structure located just below the pharynx. It connects the pharynx to the trachea and is composed of several cartilages, including the thyroid cartilage (Adam’s apple), cricoid cartilage, and epiglottis. Functions:  Sound Production: Contains the vocal cords (true vocal cords) that vibrate to produce sound when air passes through them. The tension and length of the vocal cords can be adjusted to change pitch and volume. Airway Protection: The epiglottis is a flap that covers the larynx during swallowing, preventing food and liquid from entering the trachea. Regulation of Airflow: The larynx helps control the passage of air into the trachea and regulates airflow during breathing. Trachea Description: The trachea, or windpipe, is a tube that extends from the larynx to the bronchi, which leads to the lungs. It is about 4-5 inches long and is supported by C-shaped rings of cartilage (16-20) that keep it open and allow flexibility. Functions: Air Passage: The trachea serves as a major airway, allowing air to pass to and from the lungs during breathing. Mucociliary Escalator: Lined with ciliated epithelium and mucus-producing goblet cells, the trachea traps particles and pathogens, moving them upward toward the pharynx to be expelled or swallowed. Branching into Bronchi: At its lower end, the trachea bifurcates into the right and left primary bronchi, which lead into the respective lungs. The carina is an essential structure in the respiratory system, facilitating the division of the trachea into the bronchi, playing a critical role in the cough reflex (looks like bikini bottoms) Left lung 1. Lobes: Superior Lobe: The uppermost lobe of the left lung. Inferior Lobe: The lower lobe of the left lung. 2. Features: Cardiac Notch: The left lung has a unique feature called the cardiac notch, a concave space that accommodates the heart, allowing for a smaller size compared to the right lung. Lingula: The left lung also contains a small tongue-like projection called the lingula, which is a part of the superior lobe and corresponds to the middle lobe of the right lung. 3. Function: The left lung’s lobes are responsible for gas exchange, allowing oxygen to enter the blood and carbon dioxide to be expelled during respiration. Right Lung 1. Lobes: Superior Lobe: The uppermost lobe of the right lung. Middle Lobe: The lobe located between the superior and inferior lobes, unique to the right lung. Inferior Lobe: The lower lobe of the right lung. 2. Features:  The right lung is larger and wider than the left lung due to the position of the heart. The lobes of the right lung are separated by fissures: Horizontal Fissure: Separates the superior lobe from the middle lobe. Oblique Fissure: Separates the middle lobe from the inferior lobe. 3. Function: Similar to the left lung, the lobes of the right lung are involved in gas exchange, playing a crucial role in oxygenating blood and removing carbon dioxide. Alveoli are tiny, balloon-like structures located in the lungs where gas exchange occurs. They are the final branching of the respiratory tree and play a crucial role in respiration. Surfactant is a complex mixture of lipids and proteins secreted by the epithelial cells (specifically type II alveolar cells) of the alveoli in the lungs. It plays a crucial role in reducing surface tension and facilitating efficient gas exchange. left side has little caving cardiac notch Air goes from his pressure to low pressure The diaphragm is a critical muscle for respiration, facilitating the inhalation and exhalation process by changing the volume of the thoracic cavity. Its proper function is essential for effective breathing Boyle’s Law states that the pressure (P) of a given mass of gas is inversely proportional to its volume (V) when the temperature is held constant. Dalton’s Law of Partial Pressures is a fundamental principle in chemistry and physics that describes the behavior of gas mixtures. It states that the total pressure exerted by a mixture of non-reacting gases is equal to the sum of the partial pressures of each individual gas in the mixture. 20 Question Test w/ answers and rationale 1. What is the primary role of bicarbonate ions (HCO₃⁻) in the body? A) Transport oxygen B) Regulate pH balance C) Produce energy D) Facilitate digestion Answer: B) Regulate pH balance Rationale: Bicarbonate ions help maintain the body’s pH balance by acting as a buffer that neutralizes excess acids or bases. 2. What is formed when carbon dioxide (CO₂) reacts with water? A) Oxygen B) Carbonic acid (H₂CO₃) C) Bicarbonate ions D) Hydrochloric acid Answer: B) Carbonic acid (H₂CO₃) Rationale: The reaction between CO₂ and water produces carbonic acid, which can dissociate into bicarbonate ions and hydrogen ions. 3. Which condition is characterized by a blood pH lower than 7.35? A) Alkalosis B) Acidosis C) Neutral D) Hypercapnia Answer: B) Acidosis Rationale: Acidosis occurs when the blood pH falls below 7.35, indicating increased acidity in the blood. 4. The nasopharynx is primarily involved in which function? A) Digestive B) Respiratory C) Vocalization D) Olfactory Answer: B) Respiratory Rationale: The nasopharynx is involved in respiratory functions and contains pharyngeal tonsils that trap pathogens. 5. Which part of the pharynx serves both respiratory and digestive functions? A) Nasopharynx B) Oropharynx C) Laryngopharynx D) None of the above Answer: B) Oropharynx Rationale: The oropharynx serves as a passage for both air and food, fulfilling roles in both respiratory and digestive systems. 6. What is the primary function of the larynx? A) Gas exchange B) Sound production C) Filtration of air D) Digestion Answer: B) Sound production Rationale: The larynx contains vocal cords that vibrate to produce sound when air passes through them. 7. Which structure prevents food from entering the trachea during swallowing? A) Epiglottis B) Pharynx C) Larynx D) Trachea Answer: A) Epiglottis Rationale: The epiglottis is a flap that covers the larynx during swallowing to prevent food and liquids from entering the trachea. 8. The trachea is supported by which of the following structures? A) Smooth muscle rings B) C-shaped cartilage rings C) Elastic fibers D) Bony plates Answer: B) C-shaped cartilage rings Rationale: The trachea is supported by 16-20 C-shaped cartilage rings that keep it open and flexible. 9. What is the carina? A) The point where the trachea branches into bronchi B) The flap covering the larynx C) The upper part of the trachea D) A section of the alveoli Answer: A) The point where the trachea branches into bronchi Rationale: The carina is the ridge where the trachea bifurcates into the left and right primary bronchi. 10. Which lung has a cardiac notch? A) Right lung B) Left lung C) Both lungs D) Neither lung Answer: B) Left lung Rationale: The left lung has a cardiac notch to accommodate the heart, making it smaller than the right lung. 11. What feature is unique to the right lung? A) Lingula B) Cardiac notch C) Middle lobe D) Smaller size Answer: C) Middle lobe Rationale: The right lung contains a middle lobe, which is not present in the left lung. 12. What is the function of alveoli in the lungs? A) Produce mucus B) Facilitate gas exchange C) Support the trachea D) Regulate airflow Answer: B) Facilitate gas exchange Rationale: Alveoli are the sites of gas exchange, where oxygen enters the blood and carbon dioxide is expelled. 13. What role does surfactant play in the alveoli? A) Increases surface tension B) Reduces surface tension C) Produces mucus D) Transports gases Answer: B) Reduces surface tension Rationale: Surfactant reduces surface tension in the alveoli, facilitating efficient gas exchange and preventing alveolar collapse. 14. According to Boyle’s Law, what happens to the pressure of a gas if its volume increases? A) Pressure increases B) Pressure decreases C) Pressure remains the same D) Pressure becomes negative Answer: B) Pressure decreases Rationale: Boyle’s Law states that pressure is inversely proportional to volume; as volume increases, pressure decreases. 15. What is the primary function of the diaphragm in respiration? A) It produces sound. B) It changes the volume of the thoracic cavity. C) It filters air. D) It absorbs oxygen. Answer: B) It changes the volume of the thoracic cavity. Rationale: The diaphragm contracts and relaxes to change the volume of the thoracic cavity, facilitating inhalation and exhalation. 16. Dalton’s Law of Partial Pressures states that: A) The total pressure equals the pressure of one gas. B) The total pressure equals the sum of the partial pressures of individual gases. C) The partial pressure of one gas is independent of others. D) Total pressure decreases with increased volume. Answer: B) The total pressure equals the sum of the partial pressures of individual gases. Rationale: Dalton’s Law describes how the total pressure of a gas mixture is the sum of the partial pressures of each gas in the mixture. 17. Which structure connects the larynx to the bronchi? A) Trachea B) Esophagus C) Pharynx D) Alveoli Answer: A) Trachea Rationale: The trachea, or windpipe, connects the larynx to the bronchi leading into the lungs. 18. The mucociliary escalator in the trachea functions to: A) Produce surfactant B) Move particles and pathogens upward C) Facilitate gas exchange D) Control airflow Answer: B) Move particles and pathogens upward Rationale: The mucociliary escalator traps particles and pathogens in mucus and moves them upward towards the pharynx for expulsion or swallowing. 19. The primary role of the left lung’s lingula is to: A) Facilitate gas exchange B) Provide a space for the heart C) Serve as a projection corresponding to the middle lobe D) Support the trachea Answer: C) Serve as a projection corresponding to the middle lobe Rationale: The lingula is a small projection on the left lung that corresponds to the middle lobe of the right lung. 20. How does the body maintain a neutral pH of 7.35-7.45? A) By producing more carbon dioxide B) Through the bicarbonate buffer system and kidney regulation C) By increasing lung ventilation D) By decreasing oxygen levels Answer: B) Through the bicarbonate buffer system and kidney regulation Rationale: The bicarbonate buffer system and renal regulation of bicarbonate and hydrogen ions help maintain the body’s pH within the neutral range. Connect Exams CHAPTER 17/18 -Which of the following is not an endocrine organ? Spleen Pineal gland Thymus Neurohypophysis Testis -The hypothalamus secretes eight hormones, six to regulate the anterior pituitary and two that are stored in the posterior pituitary. TRUE -Target organs most often regulate the pituitary gland via _________. negative feedback inhibition positive feedback inhibition up-regulation down-regulation antagonistic regulation -What makes a cell responsive to a particular hormone? The chemical properties of the hormone The presence of a receptor for that particular hormone The location of the gland that secretes the hormone The location of the target cells in the body The site where the hormone is secreted -Cholesterol is essential for the synthesis of steroid hormones. TRUE -Which gland is thought to play a role in establishing 24-hour circadian rhythms? Hypothalamus  Pituitary gland Pineal gland Thyroid gland Adrenal gland -Which of the following best describes a hormone? A chemical messenger transported by the bloodstream that stimulates target cells in another organ often a good distance away. Chemical messengers that diffuse from their point of origin locally to affect other cells physiology. Chemical messengers that travel across a synapse to stimulate another cell. Junctions between cells interconnecting their cytoplasm. A chemical messenger that is triggered by the binding of a ligand on the cell surface and causes a change in DNA transcription. -Which of the following is true regarding endocrine glands? They secrete substances that do not alter the metabolism of their target cells, but have extracellular effects. They secrete their products by way of ducts. They have an unusually low density of blood capillaries. They release their secretions into the blood. Their secretions may be released onto the body surface. -Antidiuretic hormone (ADH) targets the __________. Kidneys adrenal gland anterior pituitary hypothalamus  pancreas ​ - The anterior pituitary is __________ the posterior pituitary and has __________ connection to the hypothalamus. smaller than; no neuronal larger than; a neuronal larger than; no neuronal smaller than; a neuronal similar in size to; no neuronal ​ -The __________ secrete(s) __________, which promotes Na+ and water retention. adrenal medulla; epinephrine pancreas; cortisol kidneys; corticosterone adrenal cortex; aldosterone thyroid; calcitonin -Both the thymus and the pineal gland shrink after childhood. TRUE -Similar to neurotransmitters, hormones exert their action only on cells that have specific __________ that the hormones bind to. gated channels metabolic pathways receptors enzymes  Cofactors Correctly label the following glands of the endocrine system The endocrine glands are typically found along the core of the body. The hypothalamus, pituitary, thyroid, pineal, thymus, adrenals, pancreas, and gonads are just a few of the glands and organs that secrete hormones. Know how to label -The posterior pituitary secretes _________. prolactin (PRL) adrenocorticotropic hormone (ACTH)  oxytocin (OT) thyroid hormone (TH) growth hormone (GH) -Many hours after a meal, alpha (α) cells in the pancreatic islets secrete _________, which _________ blood glucose. glucagon; lowers glucagon; raises insulin; lowers insulin; raises glucocorticoids; raises -What is the name of the hormone at A? Growth hormone Prolactin  Oxytocin Follicle-stimulating hormone Adrenocorticotropic hormone -Blood clots in the limbs put a patient most at risk for _________ Hemophilia pulmonary embolism thrombocytopenia disseminated intravascular coagulation (DIC) Septicemia -Which cells aid in the body's defense processes by secreting histamine and heparin? Eosinophils Basophils Neutrophils Platelets Monocytes -This figure shows the correction of hypoxemia by a negative feedback loop. What should go in the box labeled 2? Accelerated erythropoiesis Decreased erythropoiesis Increased bone reabsorption Decreased bone reabsorption Prevention of hydroxyapatite formation -Most oxygen is transported in the blood bound to _________ the plasma membrane of erythrocytes alpha chains in hemoglobin beta chains in hemoglobin  delta chains in hemoglobin heme groups in hemoglobin -The universal donor of RBCs, but not necessarily plasma, is blood type __________. AB, Rh-negative AB, Rh-positive O, Rh-negative O, Rh-positive ABO, Rh-negative -Correctly label the parts of centrifuged blood. Plasma , Buffy coat , Erythrocytes (top to bottom) -An individual has type B, Rh-positive blood. The individual has __________ antigen(s) and can produce anti-__________ antibodies. A and D; B B and D; A B; A and D A; B and D D; A and B -How many heme groups are there in each hemoglobin molecule? 4 3 2 1 0 -Which of the following is not contained in the buffy coat? Lymphocytes Granulocytes Erythrocytes Agranulocytes Platelets -Which of the following might be injected into a patient who is prone to forming blood clots and therefore at risk of a heart attack or stroke?  Thromboplastin Fibrinogen Fibrin Heparin Factor X What is the ABO blood type of subject 2? A B AB O The main reason why an individual with type AB, Rh-negative blood cannot donate blood to an individual with type A, Rh-positive blood is because __________.  anti-A antibodies in the donor will agglutinate RBCs of the recipient anti-A antibodies in the recipient will agglutinate RBCs of the donor anti-B antibodies in the donor will agglutinate RBCs of the recipient anti-D antibodies in the donor will agglutinate RBC of the recipient anti-B antibodies in the recipient will agglutinate RBCs of the donor -The liver stores excess iron in ferritin. TRUE -Some lymphocytes can survive as long as __________. Days Weeks Months Years Decades What is the ABO blood type of subject 1? A B AB O -Where in the body are hemopoietic stem cells found? Yellow bone marrow Thymus Red bone marrow Spleen Liver -What is the most abundant protein in plasma? Insulin Creatine Bilirubin Albumin Creatinine What is the ABO blood type of subject 4? A B AB O -Serum is essentially identical to plasma except for the absence of __________. Fibrinogen nitrogenous wastes Platelets glucose albumin -Monocytes differentiate into large phagocytic cells. TRUE -What are the components of the circulatory system? Heart Blood vessels Blood Heart and blood vessels Heart, blood vessels, and blood What is indicated by the arrows? Antibodies Antigens Leukocytes Erythrocytes Megakaryocytes -Incompatibility of one person's blood with another results from the action of plasma antibodies against the RBCs' antigens. TRUE -A person with type AB blood has __________ RBC antigen(s). No anti-A and anti-B anti-A anti-B A and B What is the ABO blood type of subject 3? A B AB O This figure shows the correction of hypoxemia by a negative feedback loop. What should go in the box labeled 1? Multiple Choice Secretion of erythropoietin Secretion of gastroferritin Increased osteoblast activity Decreased osteoclast activity  Calcitriol secretion Most oxygen is transported in the blood bound to __________. the plasma membrane of erythrocytes alpha chains in hemoglobin beta chains in hemoglobin delta chains in hemoglobin heme groups in hemoglobin -Blood viscosity stems mainly from electrolytes and monomers dissolved in plasma. FALSE -Where do most RBCs die? Stomach and small intestine Red bone marrow Spleen and liver Lymph nodes and thymus Stomach and liver -This figure shows the stages of hemoglobin breakdown and disposal. What should go in the yellow box labeled 1? Heme Globin Erythropoietin Gastroferritin Transferrin LAB 1 -If the blood from an individual with type O blood is mixed with anti-A serum in one well and anti-B serum in a second separate well, the anti-A serum well will show agglutination, but the anti-B serum well will not. the anti-A serum well and the anti-B serum well both show agglutination. no agglutination will be seen. the anti-B serum well will show agglutination, but the anti-A serum well will not. -If inhibiting thyroid hormone release with PTU (propylthiouracil) in an experiment, the ___ group receives PTU and the ___ group receives no PTU. experimental; control control; experimental test group; non-test group -What effect does insulin have on blood glucose level? increase no change  Decrease -Which of the following white blood cell(s) is/are classified as a granulocyte? Check all that apply. Basophil Eosinophil Lymphocyte Monocyte Neutrophil -Place the three components of blood that separate from each other when a blood sample is centrifuged from most superior to inferior. Plasma, Buffy Coat, Foamed Elements -Where are the A, B, and Rh antigens located? Within the plasma On leukocytes On platelets On erythrocytes  Top Left : Monocyte Bottom Left : Basophil Middle : Lymphocyte Top right : Neutrophil Bottom Right : Esophil Red dots: Erthrocyte -When your body temperature is low, you rely on ________to regulate your body temperature. shivering sweating increasing metabolic rate breathing heavy -Tim has an accident and needs a fast blood transfusion. Tim's blood type is "B". The hospital ran out of type B blood, but they have AB type, A type, and O type blood. Which type would Tim receive as it will provide the least issues for him? Type A blood Type AB blood Type O blood -If thyroid hormones are not released, you can regulate body temperature by _____, which requires a greater use of _____ eating; glucose shivering; oxygen exhaling; carbon dioxide sweating; calcium When insulin is administered in excess, blood glucose level ______________producing early signs of hypoglycemia, which, if left untreated, results in a dangerous state called insulin shock. Decreases Increases -Click and drag the appropriate word or phrase form the left to accurately complete the sentences on the right. Then, rearrange the sentences to form a paragraph that explains the actions of pancreatic hormones. Start with the sentence that begins with "When blood glucose is high,etc."  When blood glucose is high, beta cells of the pancreas secrete insulin. Uptake of glucose by the liver, muscles, and fat cells increases. As a result, blood glucose levels decrease. When blood glucose levels are too low, alpha cells of the pancreas secrete glucagon. As a result, the liver releases glucose into the blood. These are each an example of a negative feedback system. -Which of the following is/are classified as a formed element of blood? Check all that apply. Plasma plasma protein Platelet red blood cell white blood cell  thymus gland suprarenal gland thyroid gland Hypothalamus pituitary gland -In order to determine the hematocrit, blood is placed in a Hemoglobinometer. coagulation tube. movable slide. Centrifuge. -Which of the following statements about insulin effects is correct? Insulin stimulates the endocytosis of GLUT4 transporters. Insulin increases the absorption of glucose by skeletal muscle, liver, and fat cells. Insulin reduces cell glucose levels. Insulin increases glucose levels in blood plasma  pineal gland pituitary gland thymus gland thyroid gland suprarenal gland -The surface of red blood cells and a person with type B blood has B antigens. anti-B antibodies. A antigens. anti-A antibodies.  AB+ O- A+ B+ -Which of the following white blood cell(s) is/are classified as an agranulocyte? Check all that apply. Basophil Eosinophil Lymphocyte monocyte neutrophil  Left atrium Left ventricle Right atrium Right ventricle Interventricular septum The surface of red blood cells in a person with type O blood has only A-antigens. both A-antigens and B-antigens. neither A-antigens nor B-antigens. only B-antigens. -When testing insulin levels on swimming fish, normoglycemia results in fast, darting movements.  slow, lethargic movements. regular, smooth movements pineal gland pituitary gland thymus gland suprarenal gland thyroid gland -What is the most abundant WBC? Neutrophil Lymphocyte Monocyte Erythrocyte -The ________ is the test to determine percentage of red blood cells.  Coagulation Hematocrit buffy coat Hemoglobin Which glands secrete their product by way of a duct directly onto an epithelial surface? Endocrine Autocrine Exocrine Paracrine Amphicrine Match the health state of the fish with its observed behavior Hyperglycemia : Fish is lethargic, unable to move dorsal fin as much Normal :Regular swimming speed Hypoglycemia (Insulin shock): Fast swimming/darting When measuring oxygen consumption to measure metabolic activity, you must take into account the ____ of the mice, which is called ____ age; averaging the data sex; normalizing the data weight; normalizing the data length; averaging the data When testing insulin levels on swimming fish, hyperglycemia results in  slow, lethargic movements. fast, darting movements. regular smooth movements. -When a blood sample is centrifuged the buffy coat represents the red blood cell percentage. hemoglobin saturation. plasma percentage. white blood cell and platelet percentage. -Which of the following blood vessels carries oxygenated blood? Check all that apply Aorta Pulmonary veins Pulmonary trunk Pulmonary arteries Venae cavae -A chemical that enters the blood and travels to eventually affect a target cell is called a Hormone. Steroid. Neurotransmitter. catecholamine. ​ -Blood is a biohazard that requires special safety precautions.  TRUE -Where would antibodies be found in the blood? On leukocytes On platelets On erythrocytes Dissolved in the plasma -Hematocrit is a measurement of the percentage of blood volume composed of which formed element? red blood cells lymphocytes basophils Neutrophils platelets pituitary gland Hypothalamus thymus gland ovary thyroid gland  hypothalamus ovary pituitary gland thyroid gland testis -Select all of the following that are formed elements in blood. red blood cells white blood cells platelets plasma -An individual with blood type O lacks both RBC antigens A and B. TRUE right ventricle left atrium interventricular septum  left ventricle right atrium The endocrine system is comprised of __________ that secrete hormones? Glands Cells Tissues All of the choices are correct None of these choices are correct. -When testing insulin levels on swimming fish, hypoglycemia results in slow, lethargic movements. regular, smooth movements. fast, darting movements. -Where are the A, B, and Rh antigens located? On leukocytes On platelets Within the plasma On erythrocytes Which of the following arrows is pointing to the diaphragm? B A C Where is the SA node is located? left ventricle left atrium right ventricle right atrium During the contraction of the left ventricle, the systemic arterial pressure reaches its maximum, which is called pulse pressure. mean arterial pressure. systolic pressure. diastolic pressure. ​ Atrial systole begins _________ immediately after the T wave  immediately before the P wave during the Q wave During the P wave. during the S-T segment -Atrial depolarization causes the _________ T wave quiescent period P wave QRS complex first heart sound -The stethoscope is placed over the _______ artery in the antecubital space when taking blood pressure. ulnar radial brachial Axillary lingual tonsil pharyngeal tonsil uvula palatine tonsil Thymus left ventricle right ventricle left atrium interventricular septum right atrium  posterior interventricular sulcus anterior interventricular sulcus coronary sulcus apex Base When the left ventricle relaxes, the blood pressure drops to its lowest level, which is called mean arterial pressure. systolic pressure. pulse pressure. diastolic pressure. gall bladder liver spleen Pancreas Stomach -Through which valves does blood exit the heart? A and C A and B C and D B and C B and D myocardium of right atrium myocardium of right ventricle myocardium of left ventricle myocardium of left artium myocardium of aorta In a blood pressure reading of 110/70, the higher value (110) is the __________ pressure. depolarization diastolic repolarization  systolic chordae tendineae interventricular septum interatrial septum trabeculae carneae papillary muscles -The apex of the heart is found __________ of the midline of the body. to the right to the left in the center -Which of the following carry oxygen-poor blood?  Aorta and pulmonary veins Pulmonary veins and pulmonary arteries Venae cavae and pulmonary arteries Aorta and vena cavae Pulmonary veins and vena cavae -Which of the following arrows is pointing to the lungs C B A  inguinal nodes thoracic nodes remnant of thymus mediastinal nodes cysterna chyli -Which letter indicates a P wave? D E A C B -What does an ECG measure? all electrical impulses cardiac cycle repolarization Depolarization -Is the trachea in front of or behind the esophagus? Behind in front How many chambers does the heart consist of? four two one three The __________ valve regulates the flow of blood between the right ventricle and the vessels leading to the lungs. right atrioventricular pulmonary aortic left atrioventricular Mitral -The __________ carry blood toward the lungs. pulmonary arteries and veins pulmonary trunk and veins aorta and pulmonary arteries pulmonary trunk and arteries superior and inferior venae cavae -The heart contracts because of an electrical impulse. Where in the heart does this impulse start? right ventricle left atrium atrioventricular node  sinoatrial node Which valve is not generally represented with three cusps? C B A and C A D Which letter represents the mitral valve? B C A D -Through which valve(s) does blood go to the lungs? B B and D A D C Blood pressure measurements are expressed as a fraction. The top number of this fraction indicates what? diastolic pressure systolic pressure pulse pressure mean arterial pressure Blood flows into vessel C from which chamber? Left ventricle Right ventricle Right atrium Coronary sinus Left atrium Where does blood in vessel E flow to? (use photo above) Lungs Lower body Right atrium Left atrium Right ventricle -Through which valve does blood flow to enter into vessel B? (use photo above) Aortic Mitral Pulmonary Left atrioventricular Right atrioventricular -The __________ is the standard artery used to determine blood pressure. femoral artery posterior tibial artery common carotid artery brachial artery Multiple Choice liver heart pancreas thyroid gland Stomach  thymus pancreas stomach spleen Liver Opening and closing of the heart valves is caused by _________ gravity osmotic gradients breathing pressure gradients -The _________ performs the work of the heart. fibrous skeleton pericardial cavity Endocardium  Myocardium Epicardium -Which letter indicates a T wave? B E D A C -Which letter indicates a QRS complex? D A  B C -Which of the following blood vessels have the lowest pressures? Capillaries Veins Venules Arterioles inguinal nodes axillary nodes mediastinal nodes cervical nodes iliac nodes myocardium of aorta myocardium of right ventricle myocardium of left artium myocardium of left ventricle myocardium of right atrium uvula palatine tonsil lingual tonsil Thymus -Blood pressure measurements are expressed as a fraction. The bottom number of this fraction indicates what? mean arterial pressure systolic pressure diastolic pressure pulse pressure pharyngeal tonsil lingual tonsil uvula palatine tonsil thymus The chordae tendineae of the AV valves are anchored to the __________ of the ventricles? interatrial septum  papillary muscles interventricular septum trabeculae carnae pectinate muscles Electrical signals pass between cardiomyocytes through the _________ gap junctions Hemidesmosomes Aquaporins Desmosomes tight junctions -Which of the following resting blood pressures would be considered normal? 120/80 mm Hg 80/50 mm Hg 130/90 mm Hg 140/95 mm Hg LECTURE EXAM 2 -The heart is enfolded within a space called the __________. myocardium pleural cavity pericardial cavity  abdominal cavity Mediastinum -The apex of the heart is found __________ of the midline of the body. in the center to the left to the right The __________ performs the work of the heart. Myocardium pericardial cavity epicardium fibrous skeleton Endocardium -The __________ are the superior chambers of the heart and the _________ are the inferior chambers of the heart. left atria; right atria left ventricles; right ventricles ventricles; atria atria; ventricles -The ventricles are the thicker more powerful chambers of the heart. They pump blood to the lungs and body. TRUE -The right atrioventricular valve (tricuspid) regulates the opening between the _________ and the _________.  left atrium; left ventricle right atrium; right ventricle right atrium; left ventricle left ventricle; right ventricle -Oxygen-poor blood passes through the _________. pulmonary and aortic valves right AV (tricuspid) and pulmonary valves left AV (mitral) and aortic valves left AV (mitral) valve only right AV (tricuspid) valve only -The __________ valve regulates the flow of blood between the right ventricle and the vessels leading to the lungs. aortic left atrioventricular mitral pulmonary right atrioventricular ​ -The __________ carry blood toward the lungs. aorta and pulmonary arteries superior and inferior venae cavae pulmonary trunk and veins pulmonary arteries and veins pulmonary trunk and arteries -Opening and closing of the heart valves is caused by _________. gravity breathing valves contracting and relaxing osmotic gradients pressure gradients -Which of the following is a feature shared by cardiac muscle and skeletal muscle? Dependence upon nervous stimulation Intercalated discs Communication via electrical (gap) junctions Autorhythmicity Muscle fiber striations ​ -The __________ is the pacemaker that initiates each heart beat. sinuatrial (SA) node autonomic nervous system atrioventricular (AV) node sympathetic division of the nervous system cardiac conduction system -The pacemaker potential is a result of _________. Na+ outflow K+ inflow K+ outflow  Ca2+ inflow Na+ inflow -The __________ provides most of the Ca2+ needed for myocardial contraction. Golgi apparatus cytoskeleton extracellular fluid sarcoplasmic reticulum In a normal ECG, the deflection that is generated by ventricular repolarization is called the __________. QRS wave S wave T wave R wave P wave -When the ventricles relax, the __________ valve prevents backflow of blood into the left ventricle. aortic pulmonary Mitral left AV right AV ​ -Parasympathetic stimulation reduces heart rate. TRUE Which structure is the pacemaker of the heart? B A E C D What is the double-walled sac that surrounds the heart called? Fibrocardium Pericardial cavity Epicardium Endocardium Pericardium -Which term refers to relaxation of the heart  Systole Bradycardia Asystole Fibrillation Diastole What is the broad flat superior top portion of the heart called? Apex Base Origin Border -Blood flow through a capillary bed is regulated by precapillary sphincters. TRUE -Increased capillary filtration, reduced reabsorption, or obstruction of lymphatic drainage can lead to edema TRUE -Most tissue fluid is reabsorbed by the lymphatic system. FALSE -Which vessels have the thickest tunica media?  Large veins Large arteries Small arteries Small veins Capillaries -Alternative routes of blood supply are called __________. preferred channels metarterioles capillary beds anastomoses thoroughfare channels -Which of the following is not a possible circulatory route from the heart? Heart → arteries → arterial anastomosis → capillary bed → veins → heart Heart → arteries → capillary bed → vein → capillary bed → arteries → heart Heart → arteries → capillary bed → vein → capillary bed → veins → heart Heart → arteries → capillary bed → veins → heart Which of the following would decrease the velocity of blood flow? Increased viscosity Decreased vasomotion Increased blood pressure Increased vessel radius How many pulmonary arteries empty into the right atrium of the heart?  4 8 0 1 Which of the following is a portal system? Heart → arteriole → artery → vein → heart Heart → artery → arteriole → capillary bed → arteriole → capillary bed → venule → vein → heart Heart → artery → vein → heart Heart → artery → arteriole → capillary bed → venule → vein → vein → heart Heart → artery → artery → arteriole → capillary bed → venule → vein → heart ​ -What is the path of blood flow from the heart to the lung tissues and back to the heart? Left ventricle → aorta → brachiocephalic artery → lung tissues → bronchial veins → brachiocephalic vein → superior vena cava → right atrium Left ventricle → aorta → bronchial arteries → lung tissues → bronchial veins → azygos vein → superior vena cava → right atrium Right atrium → pulmonary trunk → pulmonary arteries → lung tissues → pulmonary veins → left ventricle → left atrium Right ventricle → brachiocephalic arteries → lung tissues → brachiocephalic veins → inferior vena cava → left atrium Right ventricle → pulmonary trunk → pulmonary arteries → lung tissues → pulmonary veins → left atrium What type of circulatory pathway is labeled 1 in this diagram? Coronary bypass Venous anastomosis Portal system Arterial anastomosis Arteriovenous anastomosis Which term refers to the feedback response to blood-pressure changes? Baroreflex Flexor reflex Medullary ischemic reflex Chemoreflex -The pulmonary circuit is the only route in which arteries carry less oxygen than veins. TRUE -Electrical signals pass between cardiomyocytes through the __________. tight junctions desmosomes aquaporins hemidesmosomes gap junctions -Any abnormal cardiac rhythm is called a(n) __________. arrhythmia nodal rhythm sinus rhythm ectopic focus heart block -The volume of blood ejected by each ventricle in one minute is called the __________. stroke volume preload afterload cardiac reserve  cardiac output During which part of this ECG are the atria repolarizing? B E C D A Atrial depolarization causes the _________ first heart sound P wave T wave quiescent period QRS complex -The chordae tendineae of the AV valves are anchored to the _________ of the ventricles.  interventricular septum papillary muscles interatrial septum trabeculae carnae pectinate muscles ​ Atrial depolarization causes the first heart sound T wave quiescent period