BCMB 230 Exam 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 hyposecretion c a primary hypersecretion d a tertiary hypersecretion 4 The heart valve in the entrance to the systemic circulation is the a tricuspid b bicuspid c aortic semilunar 5 Which of the following is not activated by thrombin a factor 10 b platelets c factor 8 d pulmonary semilunar d factor 13 6 Which of the following hormones would be the slowest to act a cortisol b growth hormone c glucagon 7 Which hormone s is lipid soluble a T3 b epinephrine c LH d calcitonin d ACTH 8 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 oxytocin 10 Amine hormones from the thyroid act to change cell behavior by a changing membrane permeability b activating a second messenger c initiating transcription d all of the above 11 Von Willebrand factor a is produced by the liver b is activated by exposure to collagen c initiates the intrinsic clotting pathway d all of the above 12 Tropic hormones are produced by the a anterior pituitary b hypothalamus c placenta d all of the above 13 Secretion of which hormone would be controlled by a tropic hormone a estrogen b TSH c cortisol d all of the above 14 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 above 16 Production of glycogen is called a glycogenolysis b gluconeogenesis c glycogenesis d glucagon 17 Which is not an action of glucagon a decrease in the production of plasma proteins b increased plasma amino acids c decreased fat storage d promotes gluconeogenesis in liver 18 Parasympathetic stimulation of the pancreas results in the secretion of a glucagon b insulin c somatostatin d all of the above 19 Which hormone is produced by the pineal a testosterone b melanocyte stimulating hormone c growth hormone d melatonin 20 Permissive effects in the utilization of fats occur with a thyroid hormones and epinephrine b glucagon and cortisol c growth hormone and epinephrine d all of the above 21 In veins an increase in resistance typically a increases pressure b increases flow c decreases flow d both a and b 22 Osmotic pressure of the cardiovascular system is primarily produced by a blood volume b plasma proteins c plasma sodium d plasma glucose 23 The relationship between vessel length and resistance is a directly proportional and linear b inversely proportional and linear c directly proportional and exponential d inversely proportional and exponential 24 A change in plasma albumin would influence a blood pressure b hormone action 25 AV valves are closed by a atrial contraction c atrial relaxation c ultrafiltration d all of the above b ventricular contraction d ventricular relaxation 26 Vascular smooth muscle responds to increased stretch by a increasing contraction strength b decreasing contraction strength c contracting d both a and c 27 Which pacemaker does not directly interact with contractile cardiac muscle cells a SA node b AV node c Bundle of His d Purkinje fibers 28 The end diastolic volume is at the a P wave b T wave c QRS complex d L wave 29 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 inhibits cGMP 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 work b they would act together to increase systemic blood pressure c they would act together to decrease systemic blood pressure and flow d the action of Sildenafil would be greatly enhanced by NO 31 Atrial repolarization occurs during the of an EKG a P wave b T wave c QRS complex d none of the above 32 Most of the end diastolic volume enters the heart during the a P QRS interval b T P interval c P T interval 33 The first heart sounds lub occurs at the a P wave b T wave c QRS d T QRS interval d both a and c 34 Which of the following directly influences both stroke volume and heart rate a stretch b parasympathetic activity c sympathetic stimulation d all of the above 35 Contraction strength of the heart is influenced by a end diasystolic volume b stretch c sympathetic nerves d all of the above 36 Cardiac output is increased by a venous vasoconstriction c increased afterload b increased end systolic volume d all of the above 37 Afterload could be influenced by a blood viscosity c plaque decreasing artery diameter b high blood pressure d all of the above 38 Which of the following would not be produced by endothelial cells a NO b heparin c Von Willebrand factor d antithrombin 39 Active hyperemia starts with a decreased blood flow to an organ c increased metabolic activity in an organ b parasympathetic stimulation d sympathetic stimulation 40 Myogenic responses play a role in a flow autoregulation b active hyperemia c contractility d Starling s Law 41 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 pressures of plasma promote fluid to enter the capillary c low hydrostatic and high osmotic pressures of plasma promote fluid to enter the capillary d low hydrostatic and low osmotic pressures of plasma promote fluid to leave the capillary 42 Clots may be prevented by the action of a tissue factor b plasmin c