Circulatory System Review ANSWERS

Transcription

1 Circulatory System Review ANSWERS 1. Know the diagrams of the heart, internal and external. a) What is the pericardium? Double membranous sac that surrounds the heart What is myocardium? The muscle tissue that makes up the heart What is the septum? The tissue that separates the left and right side of the heart b) Explain the 4 valves of the heart. What is their function, structure, and location. Right atrium upper right chamber that receives oxygen-poor blood from the vena cava and pumps blood to the right ventricle. Right ventricle (lower right chamber) pumps blood out the pulmonary truck/artery (to the lungs). Left atrium (upper left chamber) receives oxygen-rich blood from the pulmonary veins (from the lungs) and pumps blood to the left ventricle. Left ventricle (lower left chamber) has the thickest myocardium and pumps blood out of the heart via the aorta (to body tissues) c) What are chordae tendinae? Fibrous strands that attached to the AV valves and the ventricles to prevent the ventricle from inverting 2. Know the diagram and table of the blood vessels. a) What is the major (largest) artery of the body? aorta What is the major vein of the body? Vena cava (superior and inferior) b) What is a pulse? The muscular contractions of arteries c) What is Arteriosclerosis? Hardening of the arteries which reduces elasticity of artery wall (associated with aging) Atherosclerosis? Plaque buildup in arteries due to high saturated fats and cholesterol diet. Aneurysm? Weakening of artery wall which can lead to arteries bursting (most common in arteries leading to brain) 3. Know the diagram of ECG and electrical impulses in the heart. a) Explain the electrical cardiac cycle. Medulla oblongata sends message to heart, SA node (pacemaker) in wall of right atrium receives message and causes both atria to contract. AV node at base of right atrium is stimulated by pacemaker and send message along purkinje fibres (nerve fibres within myocardium that surround each ventricle) and cause muscular tissue around ventricles to contract. The entire heart rests. b) Explain how the autonomic nervous system regulates the heartbeat. (parasympathetic and sympathetic) parasympathetic nervous system stimulation decrease heart rate (normally active at rest) whereas the sympathetic nervous system increases heart rate (response to stress) c) What is blood pressure? Pressure of blood against vessel walls created by beating heart What is systolic pressure? Highest arterial pressure What is diastolic pressure? Lowest arterial pressure (ventricle relaxing; atria contracting) 4. Name the functions of the circulatory system. a) Explain how blood pressure changes as the blood moves throughout the body. Highest at aorta, falls through arteries, very, very low in capillaries and remains low in veins b) Explain the factors that affect blood pressure. (hypotension and hypertension) exercise, cholesterol build up, vasoconstriction/vasodilation, increased or decreased blood volume. Hypotension is low BP (below 100). Hypertension is high BP (140/90 or higher) c) Explain the difference between the 5 types of blood vessels.(size, structure, thickness, function, BP, velocity.) arteries thick, muscular layer causing these vessels to be the thickest; take blood away from the heart; highest BP; highest blood velocity; low area (thin inside by structure is thick). Arterioles smaller than arteries and lead to capillaries; decreases in BP and blood velocity but increases in area due to more paths. Capillaires very thin walls and small lumen (only one RBC thick); low BP, low blood velocity, but high area. Venules larger lumen than arterioles; low BP; velocity of blood increases from capillary slightly and area decreases as compared to capillaries. Veins largest lumen; low BP (need valves to assist with blood movement), increase in blood velocity from venules (but not as high as arteries) and low area\

2 d) How is blood pressure affected by vasodilation? Dilation of vessels lowers BP Vasoconstriction? Constriction of vessels increases BP What do these 2 terms mean? Vasodilation means the relaxation of muscle layers in vessels which increases the lumen space inside the vessel whereas vasoconstriction is the contraction of the muscular layer and therefore, decreases the lumen of vessels. 5. Name three different places valves are found in the body. Inside the heart (AV valve and semi-lunar valve), in veins, at the beginning of capillary beds (precapillary sphincters) 6. Explain the 3 different vascular pathways in the body. Pulmonary circuit; systemic circuit & coronary circuit (see notes of schematic diagrams) 7. Explain the hepatic portal system. The nutrients that are absorbed within the capillaries within the villi of the small intestine are directly transferred to the liver capillaries via the hepatic portal vein Distinguish between the hepatic portal vein and the hepatic vein the hepatic portal vein is between the intestine and the liver; whereas the hepatic vein is the from the liver to the heart 8. Explain the process of capillary-tissue fluid exchange. a) What is osmotic pressure? The pressure causes by the water content within the blood and affects the blood volume as well as the exchange that occurs at the capillary level. b) How does it affect the capillaries? OP should be at about 21 mm of Hg in order for efficient exchange to occur between the ECF and the blood capillaries c) How is extra fluid taken up from tissues? Via the lymphatic capillaries d) Label the following diagram for fluid exchange. Include the pressure in mm Hg on the arteriole and venule sides of your diagram. e) What is the pressure in mm Hg in the other blood vessels? Arteriole end Venule end 9. Explain fetal circulation. a) Name 2 ways blood can bypass the lungs. Via arteriole duct or foramen ovalis b) How does the fetal circulatory system change after birth has occurred? Foramen ovalis closes and becomes an indent with the septum and arteriole duct as well as venous duct are closed off, shrink and become ligaments 10. Components of the Blood: a) What is plasma? The yellowish, liquid portion of blood that contains gases, water, proteins, wastes, hormones & salts b) What are erythrocytes? RBC Why are they able to carry such a large protein like hemoglobin? Quaternary protein with iron. c) Explain the structure and function of leukocytes. WBCs that fight infection. Larger than RBC, but fewer in number. Can be granular or agranular

3 d) What are platelets? Enucleated, Cell fragments that function in blood clotting Explain the process of blood clotting. When blood vessel is punctured, platelets congregate and form a plug. Fibrinogen (protein carried in plasma) is enzymatically converted to fibrin which forms a mesh-like network over wound and this network traps RBCs. e) What is the difference between an antigen and antibody? Antigen (a glycoprotein) is on the surface of RBCs and the body s protective response to fight anything foreign is the production of Antibodies. Antibodies attach to foreign material which flags it for destruction by the WBCs. 11. Immunity a) What is immunity? Body s ability to eliminate foreign material Explain the functions of the immune system.defend against pathogens; remove old cells; identifies and destroys abnormal cells; rejects foreign tissue b) Explain the 3 levels of the immune system Physical & chemical barriers such as skin, mucus, acidity of sweat, juices,etc.; WBC response neutrophils enlarge into macrophages which phagocytize material; antibody/antigen response see 10(e) c) Explain the inflammatory response. basophils release histamine (chemical) that causes enlargement (reddening) & increased permeability (swelling) of capillaries to attract macrophages to the area which consume bacteria from site of injury. 12. The Lymphatic System: a) What are the functions of the lymphatic system? What is the main function of it? Main: take up excess fluid from ECF; others: absorb fat from intestinal villi; destruction of foreign material; produce antibodies; b) What is the structure and function of lymph vessels? capillaries and veins with valves to prevent backflow of lymph fluid c) What is extracellular fluid (ECF)? The fluid that exists between the blood capillaries, the cells close to those capillaries and the lymph capillaries d) What are lymph nodes? collection of lymph tissue that forms swellings that produce and store lymphocytes What do they do? Filters debris from lymph fluid e) Explain the function of the different lymph organs. Spleen cleanses blood, produces lymphocytes & macrophages, stores blood. Thymus gland T-cell (a WBC) maturation. Tonsils additional immune defense. Appendix has lymph tissue to fight infection. Bone marrow makes WBCs (and RBCs) 13. Which blood vessels carry blood away from the heart? a) Capillaries b) Venules c) Veins d) Arteries e) Lymph vessels 14. Which statement is NOT a correct association? a) Arteries have muscles linings and are deep in the body b) Capillaries oxygen and nutrient exchange c) Arteries high blood pressure and are deep in the body d) Veins high blood pressure and are deep in the body they are near the surface e) Veins valves return blood to heart 15. Artery and vein are defined by whether they leave or enter the heart. If they were defined by whether they carried oxygenated or deoxygenated blood, we would have to change the name(s) of a) the hepatic portal vein to a hepatic portal artery b) the hepatic and renal systems; they would have to be switched c) the pulmonary artery and vein; they would have to be switched d) the coronary artery and vein; they would have to be switched e) none, since the aorta and vena cavae do not have artery and vein in their names 16. Which blood vessels will have walls only one cell thick? a) Capillaries b) Venules c) Veins d) Arterioles e) Arteries 17. In the fetus, the umbilical cord consists of fetal blood vessels running from the iliac artery and vein to the placenta which functions to diffuse oxygen provided by the mother. What is the nature of an artery and vein in this umbilical cord? a) They would be structurally identical and carry the same levels of hemoglobin b) Just like most arteries and veins, the artery would carry oxygenated blood and the vein would carry deoxygenated blood c) Just like the pulmonary system, the artery would carry deoxygenated blood and the vein would carry oxygenated blood

4 18. There is a condition where a baby is born with an opening (oval opening) in the septum or wall between the right and left sides of the heart. What are reasonable consequences? a) More efficient pumping of blood through the body with pressure from both ventricles b) An equal reading for heartbeat; that is diastole equals systole c) Disability resulting when deoxygenated blood is mixed and sent to the body and partly oxygenated blood is sent to the lungs d) Death due to loss of blood from the circulatory system 19. What is the correct sequence a drop of blood returning from the body encounters in the heart chambers? a) Left atrium-left ventricle-right atrium-right ventricle -left atrium-right ventricle right atrium left ventricle left atrium- right ventricle d) Right atrium- right ventricle-left atrium- left ventricle 20. What is the correct sequence a drop of blood returning from the body encounters in the heart valves? a) Right AV valve aortic semilunar valve - left AV valve pulmonary semilunar valve b) Right AV valve pulmonary semilunar valve left AV valve aortic semilunar valve c) Left AV valve pulmonary semilunar valve right AV valve aortic semilunar valve d) Left AV valve aortic semilunar valve right AV valve pulmonary semilunar valve 21. In the above diagram, a is the a) Inferior/posterior vena cava b) Superior/anterior vena cava 22. In the above diagram, c is the a) Inferior/ posterior vena cava e) AV valve e) Left atrium 23. In the above diagram, d is the a) Inferior/ posterior vena cava 24. In the above diagram, e is the a) Inferior/ posterior vena cava e) aorta e) Aorta 25. Contraction of the right ventricle forces blood initially into the a) Left atrium b) Right atrium d) Pulmonary vein e) Pulmonary artery 26. If you are tracing the path of blood from the right to the left side of the heart, you must mention the a) Lungs d) Superior/anterior vena cava b) Hepatic portal vein e) Inferior/ posterior vena cava 27. In humans, the superior (anterior) vena cava a) Carries blood to the right atrium b) Carries blood away from the right atrium 28. The pacemaker of the heart is termed the a) AV node b) Cardiac centre in the medulla oblongata c) Joins with the aorta d) Has a high blood pressure c) SA node d) Vagus nerve e) Purkinje fibres

5 29. In the above figure, which statement is true concerning blood pressure? a) It always remains the same in all vessels b) It gets progressively lower the further from the heart c) The greater the cross sectional area, the greater the pressure d) The further from the heat, the higher the pressure 30. In the above figure, which type of blood vessel would you expect to be the strongest? a) Arteries c) Capillaries b) Arterioles d) Veins 31. The alternating expansion and recoil of an arterial wall is termed a(n) a) ECG b) EEG c) Pulse 32. Systole occurs when the a) Heart tissue is contracting b) Heart tissue is relaxing d) Hypertension e) Heart murmur 33. Which is NOT a correct association describing aspects of the cardiac cycle? a) Each heartbeat constitutes a cardiac cycle b) Diastole is contraction of the heart and systole is relaxation c) A normal heart rate varies from 60 to 80 beats per minute d) A pulse is the expansion and recoil of artery walls felt near the body surface e) Valves prevent backflow of blood into the heart when the heart relaxes 34. The electrical changes that occur in the heart during contraction are recorded as a) EEGs d) EMGs b) ECGs e) MIGs c) EGGs 35. Which phase of the ECG indicates ventricular excitation and eventual contraction? a) P wave d) U wave b) QRS complex e) I wave c) T wave c) Semilunar valves open and close d) Aortic valves open and close 36. The part of the circulatory system involved with pumping blood to and from the lungs is the a) Systemic circuit d) Pulmonary circuit b) Internal respiration circuit e) ECG circuit c) Microcirculation circuit 37. Which blood vessel has the highest concentration of CO 2? a) Pulmonary artery b) Pulmonary vein 38. Oxygenated blood enters the heart at the a) Left atrium d) Renal vein e) Hepatic portal vein d) Right ventricle

6 39. Which of the following correctly traces the path of blood from the heart to the kidneys and back to the heart again? a) Left ventricle, vena cava, renal vein, kidney, renal artery, aorta, right atrium b) Right atrium, aorta, renal artery, kidney, renal vein, hepatic portal vein, vena cava, left atrium c) Left ventricle, renal artery, kidney, renal vein, vena cava, right atrium d) Left ventricle, aorta, renal artery, kidney, renal vein, vena cava, right atrium 40. Blood travelling from the intestines to the liver is travelling in the a) Pulmonary vein b) Inferior (posterior) vena cava c) Superior (anterior vena cava 41. The blood vessel that provides oxygen to the heart tissue is the a) Pulmonary artery b) Coronary artery c) Left carotid artery 42. The blood that enters the coronary artery comes from the a) Pulmonary artery b) Pulmonary vein d) Coronary vessels e) Hepatic portal vein d) Renal artery e) Left subclavian artery d) Superior (anterior) vena cava e) Inferior (posterior) vena cava 43. Blood flow in the capillaries is a) Slower because there are more capillaries and they represent more flow volume b) Faster because they are smaller and blood must speed up to get through c) The same speed as in the arteries and veins since they are the input and output points d) Highly variable due to different tissues, but must average the same as speeds in arteries and veins 44. If a person has a blood pressure of 120/80, the 120 refers to the a) Diastolic pressure b) Systolic pressure c) Pulse pressure d) Capillary pressure e) Venous pressure 45. Why is it advantageous to have blood move slowly in the capillaries? a) It will not cause damage to the valves b) It maintains the high pressure in the capillaries c) It provides time for substances to be exchanged between blood and tissue fluids d) It creates a greater osmotic pressure for cells 46. Which association is NOT correct? a) Red blood cell transport oxygen b) White blood cells fight infection c) Water maintains blood volume 47. All of the following may be found in the blood except a) Fibrinogen b) Glucose c) Urea 48. Hemoglobin is NOT a) Carried in red blood cells b) An oxygen transporter d) Oxygen cellular respiration e) Platelets fights infection d) Oxygen e) Glycogen 49. The reason red blood cells only live about 120 days is because red blood cells a) Lack a nucleus and therefore cannot defend themselves from pathogen attack b) Lack a nucleus and therefore cannot repair and rebuild cell structures c) Are attacked and eaten by white blood cells d) Are physiologically inferior cells that are not made to last very long 50. Platelets a. Phagocytize bacteria b. Are responsible for blood type c. Initiate clotting d. Transport oxygen e. Are responsible for the buildup of plaques on artery walls c) Made of protein and heme d) Normally found free in the plasma

7 51. In the above diagram, the arrow at number 2 describes the movement of a. Water d. Carbon dioxide b. Glucose e. Water, glucose, and oxygen c. Oxygen 52. In the above diagram, movement of molecules occurs in the direction of arrow 4 due to a. Diffusion d. Blood pressure b. Emulsification c. Osmotic pressure e. Filtration 53. An antibody is a) A compound that reacts with an antigen b) A white blood cell that phagocytizes invading bacteria c) A carbohydrate in the red cell membrane d) A platelet that secretes platelets 54. Which two are needed to fight infection? a) White and red blood cells b) Platelets and proteins 55. The proteins that are found in the blood a) Are formed from amino acids b) Help fight disease c) Aid in blood clotting 56. Blood pressure a) Is the same in all blood vessels b) Is highest in the aorta Label the following diagram: c) Red blood cells and platelets d) White blood cells and proteins d) Help maintain osmotic pressure e) All of the above are true c) Is measured by taking an ECG d) Never rises above normal Pulmonary Trunk/artery Umbilical Artery Aorta Arterial Duct Oval Opening Venous duct Umbilical Vein Umbilical Artery Iliac Artery