In people who stand for long periods, blood tends to pool in the lower limbs and this may result in varicose veins. Varicose veins are caused by
a) an aneurysm or weak point in an artery.
b) an aneurysm or weak point in a vein.
c) failure of the venous valves.
d) failure of the lymphatic valves.
e) a ruptured aneurysm in a vein.
Answer: c) failure of the venous valves.
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The ________ is a comma-shaped structure that lies on the surface of the testis, and includes a head, body, and tail.
Fill in the blank(s) with the appropriate word(s).
Which of the following types of force act parallel to a surface?
A. shear B. compression C. tension D. all of the above
Answer the following statements true (T) or false (F)
1. The second greatest source of water for the body is the water produced by the catabolism of food. 2. Potassium is the most common cation in intracellular fluid. 3. With slight variation, the amount of extracellular fluid equals the amount of intracellular fluid. 4. One reason the amount of water per pound increases in the elderly is that the muscle mass decreases and body fat increases.
Failure of the superior neural tube to close causes a fatal condition called
A. anencephaly. B. spina bifida. C. SIDS. D. striae gravidarum.