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Question
Melatonin can pass through plasma membranes since it is derived from the nonpolar amino acid tryptophan.
Answer
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Which of the following is a precursor to melatonin synthesis?
A. tryptophan
B. serotonin
C. tyrosine
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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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Epiphyseal growth in males is stimulated by estrogen.
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The rate at which GnRH is secreted from the hypothalamus determines whether LH or FSH is secreted from the anterior pituitary.
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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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Female accessory sex organs develop from the mesonephric ducts.
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A. 23
B. 23 pair
C. 46
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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
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What hormone may play a role in reducing the size of the uterus following delivery?
A. progesterone
B. prostaglandin
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DHEAS travels from the fetal adrenal cortex to the placenta where it is converted into oxytocin.
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Blood within the umbilical ___________ contain(s) high concentrations of fetal waste products.
arteries
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B. morula.
C. blastocyst.
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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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B. decreased, K+
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Cells synthesizing hydroxyapatite in bones are termed as
A. osteoblasts.
B. osteoclasts.
C. osteocytes.
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Bone resorption is produced by the action of _____________, which return bone calcium and phosphate to the blood.
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