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Question
What enzyme breaks the hydrogen bonds between the bases of DNA in preparation for replication?
A. DNA polymerase
B. DNA helicase
C. spliceosome
D. cyclin D
Answer
This answer is hidden. It contains 1 characters.
Related questions
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The Leydig cells of the testes constitute a blood-testis barrier that prevents autoimmune destruction of the sperm.
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Secretion of LH is inhibited by
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C. high concentrations of testosterone.
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Women do not enter a refractory period following orgasm and are capable of multiple orgasms.
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Which of the following is a precursor to melatonin synthesis?
A. tryptophan
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B. regression of the wolffian ducts during embryonic development.
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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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Female accessory sex organs develop from the mesonephric ducts.
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How many chromosomes are found in a normal human cell?
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B. 23 pair
C. 46
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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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Genetic screening of newborns using only a drop of blood can determine which of the following genetic disorders?
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
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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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A. increased, K+
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