When is a conceptus considered to be an embryo?
A. When the trophoblast and embryoblast have differentiated from each other
B. As soon as the first traces of all the organ systems are present
C. When the three primary germ layers have formed
D. When the egg is fertilized by the sperm
E. After the conceptus has implanted in the uterine wall
Answer: C
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Which of the following developmental periods is the shortest?
a. embryo stage b. fetus stage c. neonatal stage d. infancy stage
From superficial to deep, the three layers of the adrenal cortex are:
A) zona glomerulosa, zona fasciculata, zona medullaris. B) zona glomerulosa, zona fasciculata, zona reticularis. C) zona glomerulosa, zona reticularis, zona fasciculata. D) zona fasciculata, zona intermedius, zona glomerulosa.
Cytoskeletal component made of actin.
A clot that breaks loose and floats in the blood is called a(n)
A) aneurysm B) thrombus C) embolus D) plaque