Twitch summation
a. is a means by which gradation of muscle contraction may be accomplished
b. results from the additional release of Ca2+ within the cytosol of muscle fibers
c. results from increasing the frequency at which motor units are firing within a muscle
d. results from more cross bridges binding to actin within muscle fibers
e. has all of the above characteristics
E
You might also like to view...
Fertilization usually occurs in the
A) vagina. B) ovary. C) uterus. D) uterine tube.
These receptors detect changes in pressure within the body caused by the stretch or distention of internal structures.
A. Chemoreceptors B. Mechanoreceptors C. Photoreceptors D. Thermoreceptors E. Baroreceptors
Which of the following would result from a reduced function of the Na+ channels in the SA node?
A. The heart rate would decrease. B. Depolarization would be delayed. C. Depolarization would be delayed, and the heart rate would decrease. D. The plateau phase would be shorter. E. Repolarization would not occur.
The most important action of plasma albumin is
A. helping maintain colloid osmotic pressure. B. transporting lipids and fat-soluble vitamins. C. acting as antibodies of immunity. D. serving as energy sources.