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Question
The chorion frondosum develops from the ___________ layer of the chorion.
A. cytotrophoblast
B. yolk sac
C. syncytiotrophoblast
D. amnion
Answer
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Related questions
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A. tryptophan
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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. 23
B. 23 pair
C. 46
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Cryptorchid males do not produce testosterone.
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A. IgA
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C. IgF
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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
D. All of the choices are correct.
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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
D. prolactin
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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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Blood within the umbilical ___________ contain(s) high concentrations of fetal waste products.
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.
A. primary spermatocytes
B. secondary spermatocytes
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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