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Question
Ligand-gated channels, when activated, allow only Na+ to move into the neuron.
Answer
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A. tryptophan
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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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A male with 5 alpha-reductase deficiency will have male internal sex organs but more female appearing external genitals.
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What hormone is secreted by the anterior pituitary that stimulates production of milk proteins?
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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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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
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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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