What is the pacemaker that sets the rate of the heartbeat?
A. The AV node
B. The Purkinje fibers
C. The vagus nerve
D. The SA node
E. The bundle of His
D. The SA node
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Distention of the stomach
a. triggers the gastrocolic reflex. b. encourages motility in the intestines. c. results in salivation. d. both (a) and (b) above. e. both (b) and (c) above.
Implantation
A. occurs prior to fertilization. B. assists sperm cell motility in the uterus. C. occurs in the vagina. D. normally occurs in the uterus. E. occurs in the cervix.
Hyperpolarization in the postsynaptic cell is caused by ________.
A. movement of K+ out of the cell B. inhibitory postsynaptic potentials C. excitatory postsynaptic potentials D. Both inhibitory postsynaptic potentials and movement of K+ out of the cell are correct.
The levator palpebrae superioris muscle
A. contributes to laughing and smiling. B. contributes to pouting. C. raises the eyelid. D. puckers the mouth for kissing. E. causes crow's feet wrinkles.