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. Path where impulse travels from SA to AV node






2. Opposing friction force to flow - which increases with decreased radius; determined by degree of contraction of arterial smooth muscle






3. Stretching to greater degree of heart muscle causes more forceful contraction; stretching increase occur by increasing fluid volume






4. Resting membrane potential of -90mV and have long duration action potentials






5. Body's mechanism of preventing bleeding






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






7. Produced during cell metabolism and diffuses through the endothelial cells into the blood stream - where it is picked up by the liver and converted to forms that can be excreted (all other wastes are picked up by the kidneys)






8. 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






9. 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






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






11. Pass through the capillaries in order to patrol the tissue for invading organisms; only macrophages and neutrophils can squeeze through cleft






12. Protein that maintains oncotic pressure in capillaries






13. When the valve of a vein fails and back flow occurs; blood not being moved toward the heart






14. Because the veins have essentially 0 pressure - these valves ensure one - way flow - skeletal muscle contraction encourages flow through veins






15. Ensure the one - way flow through the circulatory system






16. When do semilunar valves close?






17. 2 portal systems to know






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






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






20. Store and release histamine and are involved in allergic rxns






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






22. Monocyte that phagocytoses debris and microorganisms - has amoeboid motility - and displays chemotaxis






23. Pump blood out of the heart at high pressures into arteries






24. Hematocrit or RBC those compose 35-45% of the blood; cells are non - nucleated and have no organelles. Acquire ATP through glycolysis have biconcave shape to maximize surface area for binding O2






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






26. Excessive bleeding that results from defective proteins






27. Reservoirs where blood collects from veins






28. As low as pressure gets btw heart beats in arteries






29. 55% of whole blood that is composed of electrolytes - lipoproteins - sugars - buffer - and metabolic waste






30. Essentially 0 mmHg - which results b/c of branching of vessels dissipating pressure to overcome resistance






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






32. Region that initiates start of cardiac cycle - which acts as a pacemaker of the heart; has unstable resting potential due to Na leak channels






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






34. Flow from the heart to the rest of the body; pumped by the left side of the heart






35. Connects the two capillary beds of the intestine and the liver






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






37. Receives deoxygenated blood from systemic circulation (superior and inferior vena cava)






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






39. 2 lymphocytes






40. What causes tendency of water flow out of blood?






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






42. Osmotic pressure in capillaries due to plasma proteins






43. Number of systole contractions per unit time






44. Universal acceptor






45. Voltage - gated channels that open quickly; open at threshold potential






46. Which is longer - diastole or systole?






47. Where are RBCs broken down?






48. Peptide hormone secreted from the kidneys to increase RBC production in bone marrow






49. CO2 is soluble in H2O - and thus some is dissolved and carried to lungs and tissues in plasma - O2 is not soluble in plasma at all






50. Bone marrow cells that give rise to RBC and platelets