Chapter Questions
When a conceptus arrives in the uterus, it is at what stage of development?a. zygoteb. morulac. blastomered. blastocyste. embryo
The entry of a sperm nucleus into an egg must be preceded bya. the cortical reaction.b. the acrosomal reaction.c. the fast block.d. implantation.e. cleavage.
The stage of the conceptus that implants in the uterine wall isa. a blastomere.b. a morula.c. a blastocyst.d. an embryo.e. a zygote.
Chorionic villi develop froma. the zona pellucida.b. the endometrium.c. the syncytiotrophoblast.d. the embryoblast.e. the corona radiata.
Which of these results from aneuploidy?a. Turner syndromeb. fetal alcohol syndromec. nondisjunctiond. progeriae. rubella
Fetal urine accumulates in the and contributes to the fluid there.a. placental sinusb. yolk sacc. allantoisd. chorione. amnion
Cells may be limited in how many times they can divide because of shortening of the of their chromosomes at each division.a. blastomeresb. centromeresc. telomeresd. life expectancye. autosomes
Photoaging is a major factor in the senescence ofa. the integumentary system.b. the eyes.c. the nervous system.d. the skeletal system.e. the cardiovascular system.
Which of these is not a common effect of senescence?a. reduced synthesis of vitamin Db. atrophy of the kidneysc. atrophy of the cerebral gyrid. increased risk of intervertebral disc herniatione. reduced pulmonary vital capacity
For the first 8 weeks of gestation, a conceptus is nourished mainly bya. the placenta.b. amniotic fluid.c. colostrum.d. decidual cells.e. yolk cytoplasm.
Viruses and chemicals that cause congenital anatomical deformities are called
Aneuploidy is caused by , the failure of two homologous chromosomes to separate in meiosis.
The maximum age attainable by a member of the human species is called the
The average age attained by humans in a given population is called the
Fetal blood flows through growths called ___ which project into the placental sinus.
The enzymes with which a sperm penetrates an egg are contained in an organelle called the
Stiffening of the arteries, joints, and lenses in old age may be a result of cross-linking between molecules.
An enlarged tongue, epicanthal folds of the eyes, and mental retardation are characteristic of a genetic anomaly called
The fossa ovalis is a remnant of a fetal shunt called the
A developing individual is first classified as a/an when the three primary germ layers have formed.