Standing still and at attention for long periods can result in inadequate venous return. The effects of this can be seen when even young and healthy soldiers sometimes faint when standing at attention for long periods. Which of the following is NOT occurring to promote return of blood from the venous system in this situation?
A. sympathetic activation of smooth muscle in large veins
B. skeletal muscle activity compressing veins and forcing blood flow
C. one way flow in the venous system due to valves
D. ventricular contraction
E. None of the choices for this question are correct.
B. skeletal muscle activity compressing veins and forcing blood flow
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Anury is the absence or abbreviation of the tail in sheep (and also other animals). It is inherited in an autosomal dominant fashion. A ram with anury is mated to a ewe with a normal tail. The ram’s father had anury, his mother did not. What is the probability that the ram and ewe will produce a lamb with anury? (ram = male; ewe = female)
A. 25% B. 50% C. 75% D. 100% E. No chance
The _____ have a coelom and are radial as adults
a. cnidarians c. annelids b. echinoderms d. placozoans
Which of the following shows the correct energy flow?
A) sunlight ® consumer ® producer B) sunlight ® producer ® consumer C) producer ® sunlight ® consumer D) consumer ® producer ® sunlight
Which is incorrect about Mycoplasma pneumoniae?
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