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30 Cards in this Set
- Front
- Back
When a conceptus arrives in the uterus, it is at what stage of development?
a. zygote b. morula c. blastomere d. blastocyst e. embryo |
morula
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The entry of a sperm nucleus into an egg must be preceded by
a. the cortical reaction b. the acrosomal reaction c. the fast block d. implantation e. cleavage |
the acrosomal reaction
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The stage of the conceptus that implants in the uterine wall is
a. a blastomere b. a morula c. a blastocyst d. an embryo e. a zygote |
a blastocyst
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Chorionic villi develop from
a. the zona pellucida b. the endometrium c. the syncytiotrophoblast d. the embryoblast e. the corona radiata |
the syncytiotrophoblast
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Which of these results from aneuploidy?
a. turner syndrome b. fetal alcohol syndrome c. nondisjunction d. progeria e. rubella |
turner syndrome
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Fetal urine accumulates in the_____and contributes to the fluid there.
a. placental sinus b. yolk sac c. allantois d. chorion e. amnion |
amnion
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One theory of senescence is that it results from a lifetime of damage by
a. teratogens b. aneuploidy c. free radicals d. cytomegalovirus e. nondisjunction |
free radicals
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Photoaging is a major factor in the senescence of
a. the integumentary system b. the eyes c. the nervous system d. the skeletal system e. the cardiovascular system |
the integumentary system
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Which of these is not a common effect of senescence?
a. reduced synthesis of vitamin D b. atrophy of the kidneys c. atrophy of the cerebral gyri d. increased herniation of the intervertebral discs e. reduced pulmonary vital capacity |
increased herination of intervertebral discs
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For the first 8 weeks of gestation, a conceptus is nourished mainly by
a. the placenta b. amniotic fluid c. colostrum d. decidual cells e. yolk cytoplasm |
decidual cells
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Viruses and chemicals that cause congenital anatomical deformities are called_______.
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teratogens
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Aneuploidy is caused by________, the failure of two homologous chromosomes to separate in meiosis.
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nondisjunction
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The maximum age attainable by a member of the human species is called the______.
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life span
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The average age attained by humans in a given population is called the________.
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life expectancy
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Fetal blood flows through growths called________which project into the placental sinus.
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chorionic villi
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The enzymes with which a sperm penetrates an egg are contained in an organelle called the________.
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acrosome
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Stiffening of the arteries, joints, and lenses in old age may be a result of cross-linking between_______molecules.
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collagen
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An enlarged tounge, epicanthal folds of the eyes, and mental retardation are characteristics of a genetic anomaly called________.
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down syndrome
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The fossa ovalis is a remnant of a fetal shunt called the_______.
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foramen ovale
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A developing individual is first classified as a/an______when the three primary germ layers have formed.
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embryo
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T/F Freshly ejaculated sperm are more capable of fertilizing an egg then are sperm several days old.
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False, sperm require about 10 hours to become capacitated and able to fertilize an egg.
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T/F Fertilization normally occurs in the lumen of the uterus.
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False, fertilization normaly occurs in the uterine tube.
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T/F An egg is usually fertilized by the first sperm that contacts it.
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False, Several early-arriving sperm clear a path for the one that fertilizes the egg.
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T/F By the time a conceptus reaches the uterus, it has already undergone several cell divisions and consists of 16 cells or more.
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True
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T/F The conceptus is first considered a fetus when all of the organ systems are present.
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True
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T/F The placenta becomes increasingly permeable as it develops.
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True
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T/F The endocrine system shows less senescence in old age than most other organ systems.
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True
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T/F Fetal blood bypasses the nonfunctional liver by passing through the foramen ovale.
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False, bypasses the lungs
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T/F Blood in the umbilical vein has a higher PO2 than blood in the umbilical arteries.
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True
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T/F It is well established that people who exercise regularly live longer than those who do not.
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False, exercise has proven to improve quality of live in old age, but hasn't shown to increase life expectancy significantly.
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