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Question
The ______________ are the last part of the electrical conducting system of the heart.
A. SA node
B. AV bundle
C. Bundle of His
D. Purkinje fibers
Answer
This answer is hidden. It contains 1 characters.
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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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A male with 5 alpha-reductase deficiency will have male internal sex organs but more female appearing external genitals.
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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. 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.
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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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Hypocalcemia enhances the excitability of nerves and muscles because of the ____ permeability of the cell membrane to ___.
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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
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