Circulatory and Immune Systems Quiz

The circulatory system transports blood throughout the body, carrying oxygen, nutrients, hormones, and waste products.

Arteries carry oxygenated blood away from the heart at high pressure, have thick elastic walls, and narrow lumens. Veins carry deoxygenated blood back to the heart at low pressure, have thinner walls with valves to prevent backflow, and wider lumens. Capillaries are thin-walled vessels that facilitate exchange of oxygen, nutrients, and waste products between blood and tissues.

Pulmonary circulation: Blood travels from the right ventricle of the heart to the lungs to pick up oxygen and release carbon dioxide, then returns to the left atrium. Systemic circulation: Oxygenated blood leaves the left ventricle and travels to all organs of the body, delivering oxygen and nutrients, then returns deoxygenated to the right atrium.

<p><strong>Oxygenated blood:</strong> - Left ventricle (pumping oxygenated blood to body) - Arteries (carrying oxygenated blood away from the heart) - Capillaries (facilitating exchange with tissues) <strong>Deoxygenated blood:</strong> - Right ventricle (receiving deoxygenated blood from body) - Veins (carrying deoxygenated blood towards the heart) - Capillaries (facilitating exchange with tissues)</p> Signup and view all the answers

<p>The coronary division provides blood supply to the heart muscle itself, ensuring its proper function. The coronary arteries branch off the aorta and deliver oxygenated blood to the heart wall.</p> Signup and view all the answers

<p>The heart sounds are created by the closing of the heart valves: - Lub - the closing of the atrioventricular valves (between atria and ventricles) - Dub - the closing of the semilunar valves (between ventricles and arteries).</p> Signup and view all the answers

<p>The heart's electrical wiring consists of specialized cells that generate and conduct electrical impulses, triggering muscle contractions. The sinoatrial (SA) node, known as the pacemaker, sets the tempo of the heart by initiating these electrical signals, thus regulating the heart rate.</p> Signup and view all the answers

<p>Factors that increase heart rate (tachycardia) include exercise, stress, anxiety, certain medications, dehydration, low blood oxygen levels, and some medical conditions.</p> Signup and view all the answers

<p>Normal blood pressure (resting) is typically considered to be 120/80 mmHg or lower. Systolic pressure measures the pressure in the arteries when the heart contracts, while diastolic pressure measures the pressure when the heart relaxes between beats.</p> Signup and view all the answers

<p>The lymphatic system is a network of vessels and tissues that removes waste products, excess fluid, and pathogens from the body. Lymph refers to the fluid that circulates within the lymphatic system, derived from interstitial fluid, and contains lymphocytes (white blood cells) that play a key role in the immune response.</p> Signup and view all the answers

<p>Blood is composed of: - <strong>Plasma</strong> (55%) - a liquid component containing water, proteins, electrolytes, and other substances. - <strong>Red blood cells</strong> (45%) - erythrocytes, responsible for transporting oxygen. - <strong>White blood cells</strong> (1%) - leukocytes, involved in the immune response. - <strong>Platelets</strong> (&lt;1%) - thrombocytes, involved in blood clotting.</p> Signup and view all the answers

<p><strong>Erythrocytes (red blood cells):</strong> Transport oxygen from the lungs to tissues and carbon dioxide from tissues to lungs. <strong>Leukocytes (white blood cells):</strong> Contribute to the immune response by fighting infections and foreign invaders. - <strong>Neutrophils</strong> - engulf bacteria - <strong>Lymphocytes</strong> - mediate immune responses - <strong>Macrophages</strong> - phagocytize pathogens and debris - <strong>Eosinophils</strong> - defend against parasites - <strong>Basophils</strong> - release histamine in allergic reactions <strong>Thrombocytes (platelets):</strong> Essential for blood clotting, forming a plug at the site of injury to stop bleeding.</p> Signup and view all the answers

<p>An <strong>antigen</strong> is a foreign substance (like a virus or bacteria) that triggers an immune response. An <strong>antibody</strong> is a protein produced by the immune system to specifically bind to and neutralize a particular antigen.</p> Signup and view all the answers

<p>Blood types are determined by the presence or absence of certain antigens on red blood cells. - <strong>Type A:</strong> Can donate to A and AB, receive from A and O. - <strong>Type B:</strong> Can donate to B and AB, receive from B and O. - <strong>Type AB:</strong> Can donate to AB, receive from all types (A, B, AB, O). - <strong>Type O:</strong> Can donate to all types, receive from O only.</p> Signup and view all the answers

<p>Agglutination is the clumping together of red blood cells when incompatible blood types are mixed. This occurs when antibodies in the recipient's blood bind to antigens on the donor's red blood cells, leading to a potentially life-threatening transfusion reaction.</p> Signup and view all the answers

<p>The human body has three lines of defense against pathogens: 1. <strong>First line:</strong> - Physical barriers - skin, mucous membranes, cilia, natural flora - Chemical barriers - stomach acid, lysozymes in tears and saliva 2. <strong>Second line:</strong> - Innate immune response - non-specific, rapid response - Phagocytosis by white blood cells - Inflammation - Fever 3. <strong>Third line:</strong> - Adaptive immune response - specific, slower response - Lymphocytes (B cells and T cells) - Antibody production</p> Signup and view all the answers

<p><strong>B cells:</strong> - Mature in bone marrow - Produce antibodies, which bind to and neutralize antigens - Involved in humoral immunity <strong>T cells:</strong> - Mature in the thymus - Directly kill infected cells or activate other immune cells - Involved in cell-mediated immunity - <strong>Helper T cells:</strong> - Activate other immune cells - Coordinate the immune response - <strong>Cytotoxic T cells:</strong> - Directly kill infected cells - Memory T cells: provide long-term immunity</p> Signup and view all the answers

<p>Vaccines introduce weakened or inactivated versions of a pathogen into the body. This triggers the immune system to produce antibodies and memory cells specific to that pathogen, without causing disease. When exposed to the actual pathogen in the future, the body's immune system can quickly recognize and eliminate it due to the pre-existing immunity.</p> Signup and view all the answers

<p>Autoimmune disorders occur when the immune system mistakenly attacks the body's own tissues. Examples include: - Rheumatoid arthritis - Systemic lupus erythematosus - Multiple sclerosis - Inflammatory bowel disease - Type 1 diabetes - Hashimoto's thyroiditis - Crohn's disease</p> Signup and view all the answers

<p>The excretory system filters waste products and excess fluids from the blood and eliminates them from the body. It is responsible for maintaining water balance, electrolyte balance, and blood pH, and helps remove metabolic wastes like urea and creatinine.</p> Signup and view all the answers

<p>The urinary system consists of: - <strong>Kidneys:</strong> - Pair of bean-shaped organs that filter waste products from the blood - <strong>Nephron:</strong> - Functional unit of the kidney, responsible for blood filtration - <strong>Renal pelvis:</strong> - Collects urine - <strong>Ureters:</strong> - Tubes that transport urine from the kidneys to the bladder - <strong>Bladder:</strong> - Stores urine - <strong>Urethra:</strong> - Tube that carries urine out of the body</p> Signup and view all the answers

<p><strong>Blood Flow:</strong> - Blood enters the kidneys through the renal artery - Blood is filtered in the nephrons, producing urine - Filtered blood exits the kidneys through the renal vein <strong>Urine Flow:</strong> - Urine collects in the renal pelvis - Urine travels through the ureters to the bladder - Urine is stored in the bladder - Urine is expelled through the urethra.</p> Signup and view all the answers

<p>In the nephron, <strong>filtration</strong> occurs in the glomerulus, where blood pressure forces fluids and small molecules from the blood into the Bowman's capsule. <strong>Reabsorption</strong> occurs in the proximal convoluted tubule and loop of Henle, where water, glucose, amino acids, and other essential nutrients are reabsorbed back into the blood. <strong>Secretion</strong> occurs in the distal convoluted tubule, where waste products and excess ions are secreted from the blood into the urine. These processes ensure that the body retains essential substances and eliminates waste products efficiently.</p> Signup and view all the answers

<p>The main hormones involved in the excretory system are: - <strong>Antidiuretic hormone (ADH):</strong> - Released from the posterior pituitary gland - Regulates water reabsorption in the collecting duct - Increased ADH leads to less water in urine - <strong>Aldosterone:</strong> - Released from the adrenal cortex - Regulates sodium reabsorption in the distal convoluted tubule - Increased aldosterone leads to more sodium reabsorption and increased blood volume.</p> Signup and view all the answers

<p>Kidney disorders can vary significantly in cause, symptoms, and severity. Examples discussed in class likely include: - <strong>Acute kidney injury (AKI):</strong> - Sudden onset, often reversible - Caused by sudden injury to the kidneys - Symptoms include decreased urine output, fluid retention, and fatigue - <strong>Chronic kidney disease (CKD):</strong> - Gradual deterioration of kidney function - Can be caused by diabetes, hypertension, or autoimmune diseases - Symptoms include - <strong>Urinary tract infections (UTIs):</strong> - Infection of the urinary tract (bladder, ureters, kidneys) - Commonly caused by bacteria - Symptoms include pain during urination, frequent urination, and blood in urine - <strong>Kidney Stones:</strong> - Hard deposits that form in the kidneys - Can be painful - Symptoms include severe pain in the back or side, nausea, and blood in urine</p> Signup and view all the answers

<p>Urinalysis is a laboratory test that analyzes urine to identify the presence of abnormal substances, such as blood, protein, glucose, ketones, bacteria, or red blood cells. It provides insights into kidney function, hydration status, and potential medical conditions.</p> Signup and view all the answers