BCMB 230Exam 3 Spring 2014 1. Potassium channels in cardiac pacemakers act to:a. repolarize cardiac muscle b create a plateau in cardiac membrane potentials c. cause potential to reach threshold d. create an unstable resting potential in cardiac muscle 2. Which type of ion channel found in cardiac muscle opens at resting potential?a T-type Ca b. F type Na c. L type Ca d. both a and b 3. A decrease in the release of cortisol due to a tumor in the anterior pituitary would be an example of:a. a primary hyposecretion b. a secondary hyposecretionc. a primary hypersecretion d. a tertiary hypersecretion4. The heart valve in the entrance to the systemic circulation is the:a. tricuspid b. bicuspid c. aortic semilunar d. pulmonary semilunar 5. Which of the following is not activated by thrombin?a. factor 10 b. platelets c. factor 8 d. factor 13 6. Which of the following hormones would be the slowest to act?a. cortisol b. growth hormone c. glucagon d. calcitonin7. Which hormone(s) is lipid soluble?a. T3 b. epinephrine c. LH d. ACTH8. Steroid hormones are produced by the:a. adrenal medulla b. gonads c. thyroid gland d. both a and c 9. A change in the amount of body fat would have the most influence on the distribution of which hormone?a. calcitonin b. estrogen c. glucagon d. oxytocin10. Amine hormones from the thyroid act to change cell behavior by:a. changing membrane permeability b. activating a second messengerc. initiating transcription d. all of the above11. Von Willebrand factor:a. is produced by the liver b. is activated by exposure to collagenc. initiates the intrinsic clotting pathway d. all of the above12. Tropic hormones are produced by the:a .anterior pituitary b. hypothalamus c. placenta d. all of the above13. Secretion of which hormone would be controlled by a tropic hormone?a. estrogen b. TSH c. cortisol d. all of the above14. Which hormone acts on the GI tract?a. somatostatin b. glucagon c. insulin d. all of the above 15. A decrease in plasma glucose levels would stimulate secretion of:a. glucagon b. epinephrine c. cortisol d. all of the above16. Production of glycogen is called:a. glycogenolysis b. gluconeogenesis c. glycogenesis d. glucagon17. Which is not an action of glucagon?a. decrease in the production of plasma proteins b. increased plasma amino acidsc. decreased fat storage d. promotes gluconeogenesis in liver18. Parasympathetic stimulation of the pancreas results in the secretion of:a. glucagon b. insulin c. somatostatin d. all of the above19. Which hormone is produced by the pineal?a. testosterone b. melanocyte stimulating hormone c. growth hormone d. melatonin20. Permissive effects in the utilization of fats occur witha. thyroid hormones and epinephrine b. glucagon and cortisolc. growth hormone and epinephrine d.. all of the above21. In veins an increase in resistance typically:a. increases pressure b. increases flow c. decreases flow d. both a and b22. Osmotic pressure of the cardiovascular system is primarily produced by:a. blood volume b. plasma proteinsc. plasma sodium d. plasma glucose23. The relationship between vessel length and resistance is:a. directly proportional and linear b. inversely proportional and linearc. directly proportional and exponential d. inversely proportional and exponential24. A change in plasma albumin would influence:a. blood pressure b hormone action c. ultrafiltration d. all of the above25. AV valves are closed by:a. atrial contraction b. ventricular contractionc. atrial relaxation d. ventricular relaxation 26. Vascular smooth muscle responds to increased stretch by:a. increasing contraction strength b. decreasing contraction strengthc. contracting d. both a and c27. Which pacemaker does not directly interact with contractile cardiac muscle cells?a. SA node b. AV node c. Bundle of His d. Purkinje fibers28. The end diastolic volume is at the;a. P wave b. T wave c. QRS complex d. L wave29. Nitric oxide (NO) uses a signal transduction mechanism similar to the cAMP pathway but cGMP is produced and used instead of cAMP. A number of drugs interact with this pathway. Nitroglycerin and amyl nitrate act as precursors for the production of NO. Minoxidil is likely a NO agonist and Sildenafil inhibitscGMP specific phosphodiesterase type 5. Nitroglycerin and Sildenafil tend to have localized effects while Minoxidil acts systemically. Which drug would be best for helping to control high blood pressure?a. Nitroglycerin b. Sildenafil c. Minoxidil d. how the heck should I know?30. Nitrates such as nitroglycerin and Sildenafil should not be taken at the same time because together :a. their action would cancel each other out and neither drug would workb. they would act together to increase systemic blood pressurec. they would act together to decrease systemic blood pressure and flowd. the action of Sildenafil would be greatly enhanced by NO31. Atrial repolarization occurs during the ________ of an EKG.a. P wave b. T wave c. QRS complex d. none of the above32. Most of the end diastolic volume enters the heart during the:a. P-QRS interval b. T-P interval c. P-T interval d. T-QRS interval33. The first heart sounds (lub) occurs at the:a. P wave b. T wave c. QRS d. both a and c34. Which of the following directly influences both stroke volume and heart rate?a. stretch b. parasympathetic activity c. sympathetic stimulation d. all of the above35. Contraction strength of the heart is influenced by:a. end diasystolic volume b. stretchc. sympathetic nerves d. all of the above36. Cardiac output is increased by:a. venous vasoconstriction b. increased end systolic volumec .increased afterload d. all of the above37. Afterload could be influenced by:a. blood viscosity b. high blood pressurec. plaque decreasing artery diameter d. all of the above38. Which of the following would not be produced by endothelial cells?a. NO b. heparin c. Von Willebrand factor d. antithrombin39. Active hyperemia starts with:a. decreased blood flow to an organ b. parasympathetic stimulationc. increased metabolic activity in an organ d. sympathetic stimulation40. Myogenic responses play a role in:a. flow autoregulation b. active hyperemia c. contractility d. Starling’s Law41. Which is true of the arteriole end of a capillary? a. high hydrostatic and low osmotic pressures of plasma promote fluid to leave the capillary b. high hydrostatic and low osmotic