wrong ans Flashcards
The contractile portion of the thin filament is composed of what protein?
D) actin
What is the function of T tubules?
B) They conduct action potentials from the sarcolemma to the interior of the muscle cell.
What is occurring during ventricular ejection?
D) The AV valves are closed and the semilunar valves are open as blood is leaving the ventricles.
27) Cardiac output is determined by what two variables?
E) choices B and C
B) mean arterial pressure and total peripheral resistance
C) heart rate and stroke volume
29) Which of the following would NOT result from an increase in ventricular contractility?
C) decreased end-diastolic volume
34) Resistance to blood flow is regulated primarily by what blood vessels?
C) arterioles
38) Anabolic reactions do not ________.
D) release energy
39) Glycolysis converts glucose into two ________ molecules.
D) pyruvic acid
42) Each turn of the citric acid cycle produces ________.
B) 1 FADH2, 1 ATP, and 3 NADH
45) Under normal conditions, which Starling forces favor filtration?
B) capillary hydrostatic pressure and interstitial fluid osmotic pressure
46) What factor assists venous return to the heart?
A) valves in the vein
B) the muscle pumps in the legs
C) the respiratory pump
D) the lymphatic system returning interstitial fluid
E) all of the above assist venous return
47) ________ are responsible for the detection of mean arterial pressure.
B) Arterial baroreceptors
53) Stretch receptors in the aortic arch and carotid sinus
B) serve as baroreceptors that affect vagus and sympathetic nerve activity
55) The average life span of an erythrocyte in the circulation is
e) 120 days.
56) What is the state in a skeletal muscle when there is no relaxation is occurring?
a) tetanus