ZooLec Module 5.2 Notes (1) PDF

Ika Baquir Block 13D 1 BS Life Sciences ZooLec Circulatory System: Heart, The Blood Vessels, Characteristics of Formed Elements of Blood Blood Blo...

Ika Baquir Block 13D 1 BS Life Sciences ZooLec Circulatory System: Heart, The Blood Vessels, Characteristics of Formed Elements of Blood Blood Blood Only fluid tissue in the human body Connective tissue ○ Living cells = formed elements ○ Non-living matrix = plasma Characteristics of Blood Color range ○ Oxygen rich = scarlet red ○ Oxygen poor = dull red pH level = 7.35-7.45 Hemoglobin Functions Iron-containing protein Transportation Binds strongly but reversibly to oxygen Regulation (Body temperature, volume of Each hemoglobin molecule has four water, pH of body fluids) oxygen binding sites Defense Each erythrocyte has 250 million hemoglobin molecules Leukocyte Levels in Blood Normal levels between 4000 and 11000 cells per millimeter Abnormal leukocytes levels Leukocytosis - Above 11000 leukocytes/ml - Generally indicates an infection Leukopenia - Abnormally low leukocyte level - Commonly caused by certain drugs Platelets Derived from ruptured multinucleate cells (megakaryocytes) Needed for clotting process Normal platelet count = 300,000/mm^3 Hematopoiesis Blood cell formation Ika Baquir Block 13D 1 BS Life Sciences ZooLec Occurs in red bone marrow All blood cells are derived from common stem cell (hemocytoblast) Hemocytoblast differentiation: Lymphoid - Produces lymphocytes stem cells Myeloid - Produces other formed stem cells elements Hemostasis: Stopping Blood Loss Stoppage of blood flow Result of break in blood vessel Hemostasis involves three phases ○ Vascular spasm ○ Platelet plug formation ○ Coagulation = blood clotting Fibrin Clot Fate of Erythrocytes Unable to divide, grow, or synthesize proteins ○ No nucleus Wear out in 100 to 120 days When worn out, eliminated by phagocytes in the spleen or liver Initiatives blood coagulation Lost cells replaced by division of hemocytoblasts Blood Clotting Blood usually clots within 3 to 6 minutes Control of Erythrocytes Production Clot remains as endothelium regenerates Erythropoietin = hormone that controls Clot broke down after tissue repair erythrocyte production rate Kidneys produce most erythropoietin as Undesirable Clotting response to reduce oxygen levels in the blood Thrombus - A clot in an unbroken blood Homeostasis is maintained by negative vessel feedback from blood oxygen levels - Can be deadly in areas ike heart Embolus - Thrombus that breaks away and floats freely in bloodstream - Can later clog vessels in critical areas such as brain Bleeding Disorders Ika Baquir Block 13D 1 BS Life Sciences ZooLec Based on presence or absence of two Thrombocytopenia - Platelet deficiency - Even normal movements antigens can cause bleeding from ○ Type A small blood vessels that ○ Type B require platelets for Type O = lack of antigens clotting Type AB = presence both A and B Hemophilia - Hereditary bleeding disorder - Normal clotting factors are missing Blood Groups and Transfusions Large losses of blood have serious consequences ○ 15-30% loss = weakness ○ Over 30% = shock which is fatal Transfusions = only way to replace blood quickly ○ Must be of same blood group Recipie Donor nt If someone receives blood not compatible O A B AB with one: ○ Immune system identifies it as O ✓ x x x invaders RBCs contain antigens A ✓ ✓ x x recognized by immune B ✓ x ✓ x system ○ This will lead to hemolytic reaction AB ✓ ✓ ✓ ✓ Compatibilities: Type A Antigen A, Antibody B Symptoms of ABO Incompatibility Fever and chills Type B Antigen B, Antibody A Back pain Nausea and vomiting Type AB Antigen A and B, no antibody Shortness of breath *Universal Recipient Chest pain Type O No antigen, Antibody A and B Dark urine (Hemoglobinuria) *Universal Donor Jaundice (Yellowing of skin and eyes) Rh Blood Groups Human Blood Groups Presence or Blood contains genetically determined absence of one of proteins eight Rh antigens = Antigen (foreign protein) may be attacked Agglutinogen D by immune system Problems occur Agglutination = blood is “typed” by using when mixing Rh+ antibodies that will cause blood with blood into body certain proteins to clump with Rh- blood 30 common RBC antigens Most vigorous transfusion caused by ABO and Rh blood group antigens ABO Blood Groups Rh Dangers during Pregnancy Ika Baquir Block 13D 1 BS Life Sciences ZooLec Danger only when mother Rh- and father Rh+ and child inherits Rh+ factor The Heart: Coverings Pericardium = a double serous membrane Blood Disorder Parietal Outside layer Anemia = reduction in oxygen carrying Pericardium capacity of blood Symptoms Serous fluid Fills space between layers of ○ Pale skin, headaches, fatigue, pericardium dizziness, difficulty breathing, heart palpitations Visceral Next to heart Pericardium Types ○ Iron deficiency anemia ○ Hemorrhagic anemia ○ Pernicious anemia ○ Hemolytic anemia The Heart Location ○ Thorax between lungs ○ Pointed apex directed toward left hip Size of fist The Heart: Heart Wall Three layers: Epicardium - Outside layer - Parietal pericardium - Connective tissue layer Myocardium - Middle layer - Mostly cardiac muscle Endocardium - Inner layer - Endothelium Ika Baquir Block 13D 1 BS Life Sciences ZooLec Veins carry DB back to heart through superior and inferior vena cava ○ Superior vena cava = head to heart region ○ Inferior vena cava = toes to heart region Passes through right atrium Passes through tricuspid valve Passes through right ventricle ○ Right ventricle = pumps deoxygenated blood going to lungs Passes through pulmonary valve Passes through pulmonary artery ○ Pulmonary artery = only artery that External Heart Anatomy carries deoxygenated blood CO2 removed from exhalation DB goes to the lungs Inhalation of oxygen makes blood oxygenated OB goes through pulmonary vein ○ Pulmonary vein = only vein that carries oxygenated blood Passes through left atrium Passes through mitral valve Passes through left ventricle ○ Left ventricle = thickest because it pumps blood to entire body The Heart: Chambers Passes through aortic valve Right and left side act as separate pumps Passes through aorta which brings Four chambers: blood to different parts of the body Atria Receiving Right atrium chambers Left atrium Ventricles Discharging Right ventricle chambers Left ventricle Septum = separates deoxygenated and oxygenated blood ○ One way flow of blood Blood Circulation Precursor = Cellular respiration ○ O2 needed to convert glucose to ATP is from blood circulation ○ Waste product CO2 passes through blood Arteries Oxygenated, away from heart Veins Deoxygenated, back to heart Has CO2 Ika Baquir Block 13D 1 BS Life Sciences ZooLec Mid to late Blood flows into ventricles diastole Ventricular Blood pressure builds before systole ventricle contracts, pushing out blood Early Atria finish refilling, ventricular diastole pressure low Blood Pressure Measurements by health professionals are The Heart: Valves made on pressure in large arteries Allow blood to flow in one direction Four valves: Systolic Pressure at peak of ventricular contraction Atrioventricu Between Bicuspid valve (L) lar valves atria and Diastolic Pressure when ventricles relax ventricles Tricuspid/Mitral Pressure in blood vessels decreases as Valve (R) distance away from heart increases Semilunar Between Pulmonary valves ventricle Semilunar Valve and artery Aortic Semilunar Valve Valve opens as blood is pumped through ○ Ventricle contract, valve closes Held in place by chordae tendineae = heart strings Close to prevent backflow Coronary Circulation Blood in heart chambers does not nourish myocardium Heart has its own nourishing circulatory system ○ Coronary arteries ○ Cardiac veins ○ Blood empties into right atrium via the coronary sinus Heart Contractions Contraction initiated by sinoatrial node Sequential stimulation occurs at other The Heart: Cardiac Cycle autorhythmic cells Cardiac cycle = events of one complete heartbeat Electrical Conduction System Diastole = relaxation Ika Baquir Block 13D 1 BS Life Sciences ZooLec Sinoatrial (SA) - Natural pacemaker next muscle contraction Node - Generates electrical impulses Nervous System: Regulation of Heart Atrioventricular - Delays impulse to allow Parasympatheti Decrease heart rate, blood (AV) Node complete atrial contraction c pressure, respiratory rate (rest and digest) Bundle of His - Spread impulse to ventricles and Purkinje for contraction Sympathetic Increase heart rate, blood Fibers pressure, respiratory rate (fight flight or freeze) Vascular System: Blood Vessels Vascular system provides physical pathway for blood pumped by heart Taking blood to tissues and back ○ Arteries = thicker ○ Veins = bigger ○ Capillaries ○ Venules ○ Arterioles ECG Differences between Blood Vessel Types P wave - Record of electrical activity Walls of arteries = thickest through upper heart Lumens of veins = larger chambers (atria) Skeletal muscle “milks” blood in veins QRS Complex - Record of movement of toward the heart electrical impulses through Walls of capillaries are only one cell layer lower heart chambers thick to allow for exchanges between blood and tissue ST segment - Shows when ventricle is contracting but no electricity Movement of Blood Through Vessels flowing through it - Usually appears as straight Most arterial blood is pumped by heart level line between QRS and T Veins use milking action of muscle to help move blood T wave - Shows when heart chambers are resetting electrically and preparing for Ika Baquir Block 13D 1 BS Life Sciences ZooLec ○ Triggers the SNS -> ○ Causes vasoconstriction -> ○ Raises peripheral resistance -> ○ Increases blood pressure Chemicals (e.g., renin, nicotine) ○ Stimulate SNS centers -> ○ Promote vasoconstriction-> ○ Raises peripheral resistance -> ○ Increases blood pressure Blood Viscosity ○ Increased viscosity -> ○ Higher peripheral resistance -> Pulse ○ Increases blood pressure Pulse = pressure wave of blood Key Concepts ○ Number of times arteries expand ○ Increased Stroke Volume (SV) + due to heart beating Heart Rate (HR) = Higher Cardiac Heart rate = number of times heart beats Output per minute Stroke volume = amount Monitored at “pressure points” where pulse of blood ejected from the is easily palpated left ventricle in a single heartbeat Blood Pressure: Effects of Factors ○ Vasoconstriction -> Increased Temperature Peripheral Resistance. ○ Heat = vasodilation effect ○ Both Cardiac Output and ○ Cold = vasoconstricting effect Peripheral Resistance contribute Chemicals = various substances can cause to raising Arterial Blood Pressure increase or decrease ○ Sodium = BP increase ○ Potassium = BP decrease Diet Factors Determining Blood Pressure Blood Volume ○ Increased blood volume -> ○ Kidneys conserve water and salt -> ○ Raises stroke volume (SV) -> ○ Increases cardiac output -> ○ Increases blood pressure The Respiratory System Exercise Upper Respiratory Tract ○ Helps vein transfer oxygenated Has ciliated stratified columnar epithelium blood back to heart ○ Helps vein transfer oxygenated Nasal Cavity - Air enters through nostrils blood back to heart where it is warmed, humidified, filtered by mucus ○ Activates the SNS (Sympathetic and cilia Nervous System) -> - To protect against ○ Increases heart rate (HR) and particulates and pathogens vasoconstriction -> ○ Raises cardiac output and Pharynx - Muscular tube for both peripheral resistance -> respiratory and digestive ○ Increases blood pressure - Directs air to larynx and food to esophagus Postural Changes Ika Baquir Block 13D 1 BS Life Sciences ZooLec Contains alveoli Larynx - Also known as voice box - Contains vocal chords Alveoli = tiny air sacs where gas exchange - For sound production occurs - Epiglottis = prevents food ○ Has large surface area (100 m^2) from entering trachea during for efficient oxygen absorption swallowing and carbon dioxide removal Surfactant = prevents alveoli from collapsing Lower Respiratory Tract Trachea - Rigid tube supported by C shaped cartilage rings that prevents collapse - Branches into bronchi Bronchi and - Trachea divides into two Protective Mechanisms Bronchioles primary bronchi (left and right) which further branch into Mucociliary - Mucus traps particles and smaller bronchioles leading to Escalator pathogens alveoli - Cilia moves mucus upwards - Structures resemble inverted towards throat for expulsion tree, facilitating air distribution throughout lungs Warmth and - Nasal cavity warms and Humidity humidifies air to prevent Regulation damage to lung tissues from cold or dry air Physiology of Breathing Lungs Inhalation Ika Baquir Block 13D 1 BS Life Sciences ZooLec ○ Diaphragm contracts and moves downward, creating negative pressure in the thoracic cavity, which allows air to flow into lungs ○ Intercostal muscles between ribs also contract, expanding chest cavity further ○ Blood towards heart Exhalation ○ Diaphragm relaxes, reducing thoracic volume and pushing air out of the lungs ○ Blood away from heart Hiccups = sudden entry of air which leads to diaphragm to contract involuntarily Gas Exchange Occurs in alveoli through diffusion Oxygen from inhaled air diffuses across the alveolar walls into surrounding capillaries Carbon dioxide from blood diffuses into alveoli to be exhaled