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Question
Which of the following is NOT an essential amino acid?
A. leucine
B. valine
C. lysine
D. proline
Answer
This answer is hidden. It contains 10 characters.
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Which of the following is a precursor to melatonin synthesis?
A. tryptophan
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The role of melatonin in puberty of humans is well established and critical.
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Pubic and axillary hair growth at puberty is from increased secretion of
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C. androgens from the adrenal cortex.
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Epiphyseal growth in males is stimulated by estrogen.
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A male with 5 alpha-reductase deficiency will have male internal sex organs but more female appearing external genitals.
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Males lacking testosterone receptors would
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Treating a male fetus with antibodies to DHT would prevent development of the epididymides.
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B. 23 pair
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Cryptorchid males do not produce testosterone.
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What hormone is secreted by the anterior pituitary that stimulates production of milk proteins?
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A. hypothyroidism
B. cystic fibrosis
C. sickle cell anemia
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What hormone may play a role in reducing the size of the uterus following delivery?
A. progesterone
B. prostaglandin
C. oxytocin
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DHEAS travels from the fetal adrenal cortex to the placenta where it is converted into oxytocin.
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Cortisol from the fetal adrenal gland will stimulate maturation of the lungs and production of surfactant.
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arteries
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A. zygote.
B. morula.
C. blastocyst.
D. embryo.
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The progressive fusion of the acrosomal membrane with the plasma membrane of the sperm is called the
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After meiosis I in males, ________ are formed.
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B. secondary spermatocytes
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B. decreased, K+
C. increased, Na+
D. decreased, Na+
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Cells synthesizing hydroxyapatite in bones are termed as
A. osteoblasts.
B. osteoclasts.
C. osteocytes.
D. osteosarcoma cells.
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Bone resorption is produced by the action of _____________, which return bone calcium and phosphate to the blood.
A. osteoblasts
B. osteoclasts
C. osteocytes
D. calcitonin