The heart sound associated with S2 occurs as the ventricles __________ and the semilunar valves _________.
a. relax; close
b. relax; open
c. contract; close
d. contract; open
Ans: a. relax; close
You might also like to view...
The ________________________________________ refill time of a healthy animal should be less than one or two seconds
Fill in the blank(s) with correct word
Damage to the septal cells of the lungs would most likely result in
A) a thickening of the respiratory membrane. B) an increased rate of gas exchange. C) alveolar rupture. D) reduction in surfactant production. E) decreased surface tension in the alveoli.
What type of hormones can cross the plasma membrane to bind to a receptor in the cytosol or nucleus?
What will be an ideal response?
Which one of the following is an extension of plasma membrane?
A) centrioles B) centromeres C) microfilaments D) cilia E) microtubules