The first of the extraembryonic membranes to appear, which ultimately becomes involved in blood cell formation, is (the)
A) allantois.
B) yolk sac.
C) amnion.
D) chorion.
E) None of the answers are correct.
B) yolk sac.
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Which of the following is arranged in correct order from the most complex to the simplest?
A) cellular, tissue, molecular, system, organ, organism B) molecular, cellular, tissue, organ, system, organism C) tissue, cellular, molecular, organ, system, organism D) organ, organism, molecular, cellular, tissue, system E) organism, system, organ, tissue, cellular, molecular
Answer the following statements true (T) or false (F)
1. In alkalosis, the hydrogen ion concentration of the blood rises. 2. The proper ratio of the buffer pair would be 20 times more carbonic acid than sodium bicarbonate. 3. The proper ratio of the buffer pair would be 20 times more sodium bicarbonate than carbonic acid. 4. Uncontrolled diabetes or prolonged diarrhea can lead to metabolic alkalosis. 5. Bicarbonate deficit can lead to metabolic acidosis.
A positive Babinski reflex is observed when the:
A) toes curve or move downward when the sole of the foot is touched. B) patient responds to pain by flexing the arms and extending the legs. C) patient's reflexes are hyperactive in response to an external stimulus. D) toes move upward in response to stimulation of the sole of the foot.
In which order would blood flow through these structures as it travels from the hypothalamus to the pituitary gland? a: Primary plexusb: Secondary plexusc: Hypophyseal portal veins
A. b - a - c B. a - b - c C. c - a - b D. c - b - a E. a - c - b