Test your basic knowledge |

MCAT Biology Circulatory System

Subjects : mcat, health-sciences
Instructions:
  • Answer 50 questions in 15 minutes.
  • If you are not ready to take this test, you can study here.
  • Match each statement with the correct term.
  • Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.
1. Opposing friction force to flow - which increases with decreased radius; determined by degree of contraction of arterial smooth muscle






2. Vessels where deoxygenated blood from coronary sinus continue to flow into heart






3. Filling of the ventricles by squeezing of the atria - marks the beginning of the 'dub' sound






4. Number of systole contractions per unit time






5. Receptors in the carotid arteries and aortic arch that notify CNS if blood pressure is high or low






6. Neural sympathetic input by postganglionic neuron of norepinephrine innervating arterial smooth muscle






7. AV valve between left atrium and left ventricle






8. Destroy parasites and are involved in allergic rxns






9. Absorbed in the intestine and packaged in chylomicrons - which enter the lymphatic system - and dumped into the subclavian vein via the thoracic duct; the liver takes fats once in blood - converts them to another lipoprotein and sends them to adipocy






10. Allow Na to leak across membrane - causing cell potential to get closer to threshold potential; allow threshold to be reached for Ca channels to open let Ca into the cell






11. Glycoproteins that are coded for by 3 alleles (A - B - i)






12. Response by CNS when blood pressure is too high






13. Where blood passes through 2 sets of capillaries before returning to the heart; Evolved as direct transport routes






14. 20% transported stuck to hemoglobin; why increased pCO2 decreases affinity of O2






15. Open when threshold is reached causing membrane potential to increase/depolarize; operate slower than Na channels






16. What is the most important plasma protein in the body? Why?






17. Pool of deoxygenated blood at low pressure - which collects blood from coronary veins - Only deoxygenated blood to not enter the right atrium via the vena cava






18. Large particles consisting of fats - cholesterol - and carrier proteins; transport lipids through the blood stream






19. Crosses septum and connects to Purkinje fibers to allow coordinated contraction of ventricles. Key is that is slows transmission across septum to allow ventricles to fully fill before contraction






20. Transportation of blood though the body and exchange of material btw blood and tissues






21. Precursor to fibrin - which is necessary for blood clotting






22. Request by tissues to increase blood flow - where build up of metabolic waste causes arterioles to dialate






23. Have single layer endothelial cells w/ spaces in between cells called intercellular cleft






24. Lipoproteins that enter lacteal vessels of lymphatic system in the intestinal wall






25. Universal acceptor






26. Metabolic waste product in breakdown of amino acids






27. Inadequate blood flow - resulting in tissue damage due to shortage of O2 and nutrients - and increase of metabolic waste






28. Reservoirs where blood collects from veins






29. Contraction of the ventricles - where pressure increases rapidly - causing AV valves to close - Marks the beginning of the 'lub' sound






30. 55% of whole blood that is composed of electrolytes - lipoproteins - sugars - buffer - and metabolic waste






31. Key proteins for the function of the immune system that are produced and released by B- cells






32. Protein that maintains oncotic pressure in capillaries






33. Capillaries dilate - increasing the cleft size - which allows more H2O to move through to tissues






34. When do semilunar valves close?






35. Force per unit area exerted by blood on walls of arteries






36. Where are RBCs broken down?






37. At the end of the capillary - is the osmotic pressure high or low?






38. Glucose - amino acids - and fats






39. Occurs when increased cardiac output is needed; the postganglionic nerve directly innervates the heart - releasing norepinephrine - increasing heart rate and force of contraction






40. Purpose of erythrocytes?






41. The principle sugar in blood that maintains a relatively constant concentration for adequate nutrition






42. Adequate circulation - but O2 supply is reduced (no build up waste products or loss of nutrients)






43. Caused by closure of Ca channels and opening of K channels






44. 3 substances that can diffuse through intercellular cleft






45. AV valve between right atrium and right ventricle






46. Universal donor






47. Return of blood to the heart by the vena cava - where increased venous return causes increased stretching of the muscle (increases stroke volume)






48. Protein in RBC that transport O2 though the blood since O2 is too hydrophobic in plasma; protein has 4 subunits that change confirmation cooperatively depending on the concentration of O2






49. Voltage - gated channels that stay open longer than Na channels and open later responsible for the plateau phase of cardiac muscle contraction






50. 1. depolarization caused by fast Na channels - where action potential through intercalated discs reaches threshold potential - opening Na channels 2. initial depolarization with Na channels closing and k channels opening - but Ca channels also open 3