What factors are involved in the formation of varicose veins?
A) Varicose veins form when blood pressure is too high damaging the valves.
B) Varicose veins form when blood pressure is too low so the valves do not open.
C) Varicose veins form when the vein walls weaken and the valves fail so blood begins to pool in the veins.
D) Varicose veins form when the valves become stiff and fail to open.
E) Varicose veins form when sympathetic activation causes venoconstriction.
Answer: C
You might also like to view...
Which of the following is false regarding acetylcholine?
A. It is rarely used in the body. B. It is the neurotransmitter used at the neuromuscular junction. C. It is stored and released by the presynaptic cell. D. It is synthesized from acetic acid and choline.
Damage to which spinal cord component will affect only motor activity?
a. spinal nerve b. dorsal root c. ventral root d. ascending tracts e. dorsal root ganglion
What is the stimulus that change the postsynaptic neuron membrane from resting to -85 mV?
A. Threshold B. Graded potential C. Reciprocal inhibition D. Inhibitory stimulus
The motor (efferent) division of the peripheral nervous system
A. transmits impulses from the CNS to effectors, such as skeletal muscle. B. detects presence of food in the stomach. C. has nerve cell bodies located in ganglia near the spinal cord and brain. D. is a division of the CNS. E. detects a stimulus.