The __________ is a low-pitched sound caused by vibration of the atrioventricular valves and surrounding fluid as the valves close at the beginning of ventricular systole.
a. first heart sound
b. second heart sound
c. third heart sound
d. fourth heart sound
a. first heart sound
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Glycolysis, formation of acetyl CoA, Krebs cycle and the electron transport chain are all involved in
a) Lipogensis b) Gluconeogenesis c) Glucose catabolism d) Formation of Glycogen e) Formation of vitamin C
Which of the following is FALSE regarding the membrane potential?
A) The resting membrane potential is determined mainly by the concentration gradients and differential permeability of the plasma membrane to K+ and Na+ions. B) The resting membrane potential is maintained solely by passive transport processes. C) The resting membrane potential occurs due to active transport of ions across the membrane due to the sodium-potassium pump. D) In their resting state, all body cells exhibit a resting membrane potential.
Which are functions of the skin? Choose all that apply.
A. Produce body heat B. Eliminate ammonia, urea C. Prevent water loss D. Excrete excess water
A circular muscle that acts as a valve is called a
A. plicae. B. epiglottis. C. sphincter. D. diaphragm.