chapter 29 inheritance
) In ________, implantation occurs somewhere other than in the uterus. A) ectopic pregnancy B) hydramnios C) placenta previa D) abortion E) spontaneous abortion
a
A mother has a lot of milk stored in the breast and mammary glands but cannot seem to expel the milk for her newborn. Her doctor thinks that the cause may be A) low levels of oxytocin. B) high levels of HCG. C) low levels of estrogen. D) low levels of progesterone. E) unresponsive smooth muscle around the mammary glands.
a
A zygote whose genotype is XX will develop as a A) female. B) male.
a
An infant born ________ prematurely has a good chance of survival. A) 1.5 months B) 3 months C) 5 months D) 7 months
a
During gestation, contraction of the myometrium is inhibited by ________, produced by the corpus luteum. A) progesterone B) estrogen C) oxytocin D) prostaglandins E) inhibin
a
During implantation, the A) trophoblast erodes a path through the endometrium. B) inner cell mass begins to form the placenta. C) maternal blood vessels in the endometrium are walled off from the blastocyst. D) entire trophoblast becomes syncytial. E) inner cell mass is temporarily deprived of nutrients.
a
Ectoderm is to ________ as mesoderm is to ________. A) neural tissue; muscle tissue B) cardiovascular system; neural tissue C) mesoderm; endoderm D) neural tissue; epithelial tissue E) muscle tissue; nerve tissue
a
Events in the first 12 weeks of gestation establish the basis for ________, the process of organ formation. A) organogenesis B) morphogenesis C) gametogenesis D) teratogenesis E) embryogenesis
a
If a color-blind (X-linked recessive trait) man marries a woman who is heterozygous for the trait, what proportion of their male offspring can be expected to be color blind? A) 1/2 B) 1/4 C) 1/8 D) 3/4 E) 100 (all)
a
In a(n) ________, an incision is made in the perineal musculature. A) episiotomy B) lumbar puncture C) crowning D) epidural E) peritoneal cut
a
In simple autosomal inheritance, phenotypic characters are determined, or controlled, by A) a single pair of alleles. B) multiple alleles. C) the action of a single gene. D) regulator genes on a different chromosome. E) the genes on the Y chromosome.
a
Sperm cannot fertilize an oocyte until they A) undergo capacitation. B) undergo meiosis. C) lose their flagellum. D) are in the vagina for 3 days. E) are activated by sustentacular cells of the vagina.
a
The ________ is formed by the allantois, blood vessels, and yolk sac. A) umbilical cord B) chorion C) chorioallantoic membrane D) trophoblast E) amnion
a
The blood vessel that carries oxygenated blood away from the placenta is the A) umbilical vein. B) iliac veins. C) umbilical arteries. D) uterine veins. E) uterine arteries.
a
The developmental period that is the period of all embryological and early fetal development is A) the first trimester. B) the second trimester. C) the third trimester. D) infancy. E) adolescence.
a
The extraembryonic membrane that forms blood is the A) yolk sac. B) amnion. C) allantois. D) chorion. E) decidua.
a
The first stage of labor is the ________ stage. A) dilation B) expulsion C) placental D) decidual E) neonate
a
The formation of different types of cells required in development, or ________, occurs through selective changes in genetic activity. A) differentiation B) cupellation C) deployment D) gametogenesis E) phylogeny
a
The gradual modification of anatomical structures during the period from conception to maturity is A) development. B) differentiation. C) embryogenesis. D) capacitation. E) All of the answers are correct.
a
The mesoderm forms A) muscle. B) epidermis. C) the brain. D) the lining of the digestive tract. E) respiratory epithelium.
a
The period of gestation when the rudiments of all major organ systems are established is the ________ trimester. A) first B) second C) third
a
The presence of a recessive gene can be detected (seen) only if the individual is A) homozygous recessive. B) heterozygous dominant. C) heterozygous recessive. D) homozygous dominant. E) epistatic recessive.
a
The process by which a viable embryo is formed is called A) embryogenesis. B) organogenesis. C) gametogenesis. D) morphogenesis. E) blastogenesis.
a
The process of cell division that divides the cytoplasm of the zygote among blastomeres is called A) cleavage. B) implantation. C) placentation. D) embryogenesis. E) blastulation.
a
Twins that occur when blastomeres separate are called A) monozygotic. B) blastulatory. C) zygoblastic. D) dizygotic. E) fraternal.
a
Where in the embryo does mesoderm first appear? A) between the cell layers of the inner cell mass B) within the blastocoele C) in the chorionic villi D) above the epiblast E) around the trophoblast
a
Which embryonic germ layer forms the brain and spinal cord? A) ectoderm B) endoderm C) trophoderm D) epiderm E) mesooderm
a
Which of the following is not part of oocyte activation? A) softening of the zona pellucida B) influx of sodium ion C) membrane depolarization D) release of calcium ion from smooth ER E) discharge of exocytotic vesicles
a
________ are nearly identical cells that are produced by early cleavages. A) Blastomeres B) Morulas C) Gastrulas D) Amnions E) Blastulas
a
) The neonatal period extends A) for the first 24 hours of life. B) for the first month of life. C) until the first birthday. D) from day 1 until day 60. E) until breast feeding stops
b
Blood flows to the placenta through ________ umbilical artery(ies). A) 1 B) 2 C) 3 D) 4 E) 5
b
By day 12 of embryonic development, mesoderm begins to form through A) embryolization. B) gastrulation. C) mitosis. D) meiosis. E) None of the answers is correct.
b
Fraternal twins result from A) one egg that is fertilized by two different sperm. B) two different zygotes. C) one zygote that splits into two zygotes. D) two eggs fertilized by one sperm cell. E) a blastula that splits into two blastulas.
b
How many chromosomes do human gametes contain? A) 12 B) 23 C) 46 D) 92 E) 6
b
If an individual carries a pair of alleles that are the same, the individual is ________ for the trait. A) homologous B) homozygous C) heterozygous D) autosomous E) polygenic
b
In ________, a sample of amniotic fluid is removed and the fetal cells it contains are analyzed. A) chorionic villus sampling B) amniocentesis C) paracentesis D) amniosis E) thoracentesis
b
In polygenic inheritance, phenotypic characters are A) determined by a double pair of alleles. B) determined by interactions among several genes. C) determined by multiple copies of a single gene. D) always controlled by genes on the same chromosome. E) determined by the genes on the Y chromosome.
b
Initially, the nutrients absorbed by the trophoblast easily reach the inner cell mass by simple A) osmosis. B) diffusion. C) peristalsis. D) ciliary action. E) convection.
b
Oxygenated blood from the placenta returns to the fetus in the A) allantois. B) umbilical vein. C) umbilical arteries. D) decidua capsularis. E) umbilical capillaries.
b
Proteolytic enzymes that digest a path through the zona pellucida include A) hyaluronidase and hCG. B) hyaluronidase and acrosin. C) acrosin and collagenase. D) relaxin and hyalouronidase. E) acetic acid and hydrochloric acid.
b
The 23rd set of chromosomes determines A) characteristics of the brain. B) sex. C) body characteristics. D) blood type. E) sex drive.
b
The almost identical cells produced by cleavage divisions are called A) centromeres. B) blastomeres. C) telomeres. D) myosomes. E) somal cells.
b
The clear liquid secreted by the mammary glands before milk production begins is called A) milk. B) colostrum. C) serum. D) plasma. E) peritoneal.
b
The developmental period heralded by the onset of puberty is known as A) post-infancy. B) adolescence. C) early childhood. D) teenage years. E) pre-teen.
b
The extraembryonic membrane that forms a fluid-filled sac is the A) yolk sac. B) amnion. C) allantois. D) chorion. E) decidua.
b
The extraembryonic membrane that gives rise to the umbilical cord is the A) yolk sac. B) allantois. C) amnion. D) chorion. E) decidua.
b
The gene for normal skin pigment (A) can also code for the recessive trait of albinism (a). An albino man and a homozygous normal pigmented woman marry and have four children. What is the phenotype of the children? A) 75% normal skin pigment and 25% albino B) 100% normal skin pigment C) 50% normal skin pigment and 50% albino D) 100% normal skin pigment E) 100% albino
b
The infancy stage of life is considered to be over at A) 3 months B) age 2. C) 6 months. D) 1 month. E) 18 months.
b
The layer of follicle cells that surround the unfertilized egg is called the A) zona pellucida. B) corona radiata. C) Graafian follicle. D) functional zone. E) tunica follicularis.
b
The penetration of the endometrium by the blastocyst is referred to as A) cleavage. B) implantation. C) placentation. D) embryogenesis. E) fertilization.
b
The period of gestation when organs and organ systems complete most of their development and the fetus looks distinctly human is the ________ trimester. A) first B) second C) third
b
The prostaglandins produced in the endometrium A) initiate the release of oxytocin for parturition. B) stimulate smooth muscle contractions. C) initiate secretory activity in the mammary glands. D) promote breast development. E) All of the answers are correct.
b
The trophoblast has many of the characteristics of ________ cells. A) cardiac B) cancer C) infectious D) rejuvenating E) epithelial
b
Which of the following does not occur at puberty? A) FSH levels rise. B) GnRH levels decline. C) Levels of sex hormones rise. D) Gametogenesis begins. E) Secondary sexual characteristics begin to develop.
b
________ is the percentage of individuals with a particular genotype that actually show the "expected" phenotype. A) Blending B) Penetrance C) Codominance D) Genome imprinting E) Pangenesis
b
) If an individual carries two different alleles for the same trait, the individual is ________ for the trait. A) homologous B) homozygous C) heterozygous D) autosomous E) polygenic
c
A ________ allele is expressed only when homozygous. A) homologous B) homocentric C) recessive D) maternal E) dominant
c
A blastocyst is a(n) A) extraembryonic membrane. B) solid ball of cells. C) hollow ball of cells. D) portion of the placenta. E) origin of the urinary bladder.
c
A space opens within the inner cell mass that will form the A) blastocoele. B) lacunae. C) amniotic cavity. D) chorion. E) allantois.
c
By the end of gestation, maternal blood volume normally increases by almost ________ percent. A) 20 B) 25 C) 50 D) 80 E) 100
c
Differentiation among blastomeres is the result of A) enzymes introduced by the sperm. B) hormones produced by the ovum. C) an unequal distribution of regulatory molecules in the cytoplasm of the ovum. D) regulator molecules supplied by cells of the uterus. E) enzymes activated by the sperm.
c
During amphimixis, A) sperm become haploid. B) the ovum finishes meiosis II. C) the male and female pronuclei fuse. D) meiosis occurs. E) gametes are formed.
c
During gastrulation, A) the blastomeres fuse. B) the placenta penetrates the endometrium. C) three germ layers are formed. D) cells from the hypoblast move to the epiblast. E) the neural tube closes.
c
Genes that appear on the X chromosome are said to be A) somatic. B) polygenic. C) X-linked. D) autosomal. E) chromosomal.
c
How many chromosomes do human somatic cells contain? A) 12 B) 23 C) 46 D) 92 E) 6
c
Identical twins that share body structures are called Siamese or ________ twins. A) zygotic B) attached C) conjoined D) nonidentical E) partotic
c
If a sperm carrying the "Y" chromosome fertilizes the ovum, the resulting offspring will be A) haploid. B) Rh positive blood type. C) male. D) fraternal twins. E) female.
c
Stretching of the cervix causes an increase in the blood levels of A) estrogen. B) progesterone. C) oxytocin. D) relaxin. E) chorionic gonadotropin.
c
The blood vessels that carry deoxygenated blood to the placenta are the A) umbilical veins. B) iliac veins. C) umbilical arteries. D) uterine veins. E) uterine arteries.
c
The ectoderm forms A) muscle. B) blood. C) neural tissues. D) the lining of the digestive tract. E) the urinary system.
c
The gradual modification of anatomical structures and physiologic characteristics from fertilization to maturity is termed A) gametogenesis. B) ontogeny. C) development. D) transformation. E) disablement.
c
The hollow cavity within the blastocyst is the A) blastula. B) gastrula. C) blastocoele. D) trophoblast. E) ootid.
c
The inner cell mass of the blastocyst will A) form the placenta. B) form the morula. C) form the embryo. D) form blood vessels of the placenta. E) provide nutrients for early growth.
c
The mesoderm and the trophoblast combine to form the A) amnion. B) amniotic sac. C) chorion. D) allantois. E) inner cell mass.
c
The period of gestation that is characterized by rapid fetal growth and fat deposition is the ________ trimester. A) first B) second C) third
c
The traits of an individual controlled by his or her genotype are his or her A) pleiotype. B) allotype. C) phenotype. D) isotype. E) genotype.
c
Under the influence of the trophoblast, maternal blood vessels in the endometrium A) disappear. B) attach to the inner cell mass. C) break down and form sinuses or lacunae. D) form a capillary network in the trophoblast. E) increase in size and penetrate the blastocyst.
c
Which of the following statements concerning development is false? A) The term induction refers to the chemical interplay between developing cells. B) The developing oocyte receives molecules that affect development from the surrounding granulosa cells. C) Each blastomere in the blastula receives exactly the same cytoplasmic composition. D) Differences in a cell's cytoplasmic makeup affect the cell's genetic activity. E) Cells release molecules that affect the developmental process of neighboring cells.
c
Which of these statements about ectopic pregnancy is false? A) The embryo may implant in the uterine tube. B) The mother's life may be endangered. C) Vaginal delivery is often possible. D) It occurs in less than 1 percent of pregnancies. E) It does not yield a viable embryo.
c
________ is the medical specialty that focuses on postnatal development from infancy to adolescence. A) Geriatrics B) Orthopedics C) Pediatrics D) Psychiatrics E) None of the answers is correct.
c
The region known as the primitive streak is the site of A) migration of mesodermal cells to form the endoderm. B) endoderm formation. C) ectoderm formation. D) migration of ectodermal cells to form the mesoderm. E) amnion formation.
d
The site where fertilization normally occurs is in the A) cervix. B) fimbrae. C) uterine wall near the fundus. D) outer one-third of the uterine tube. E) union of the vagina and uterus
d
The solid ball of cells that has been likened to a mulberry is called a A) chorion. B) blastula. C) gastrula. D) morula. E) blastocyst.
d
The stage of labor during which the fetus emerges from the vagina is called the ________ stage. A) emergence B) dilation C) placental D) expulsion E) fetal
d
The term ________ refers to the time spent in prenatal development. A) transformation B) micturition C) parturition D) gestation E) cleavage
d
Uterine contractions that are irregular and brief that occur toward the end of gestation are called A) parturition. B) expulsion. C) true labor. D) false labor. E) dilation.
d
Which embryonic germ layer forms connective tissues such as bone and cartilage? A) epiderm B) trophoderm C) ectoderm D) mesooderm E) endoderm
d
Which embryonic germ layer forms the linings of the respiratory and digestive tracts? A) mesoderm B) ectoderm C) trophoderm D) endoderm E) epiderm
d
Which of the following statements about the trophoblast is false? A) It secretes hyalouronidase to erode endometrial cell adhesion. B) It absorbs nutrients released by degenerating endometrial glands. C) It has both an acellular and cellular component. D) It is derived from the inner cell mass. E) It causes maternal blood vessels to break down.
d
A ________ allele will always be expressed regardless of what the other allele happens to be. A) homologous B) homocentric C) recessive D) maternal E) dominant
e
A woman who is heterozygous for blood type A mates with a man who is homozygous for blood type O. What blood type(s) would their children have? A) 75% heterozygous type A B) 100% type A C) 75% homozygous type O D) 100% type O E) 50% type A, 50% type O
e
After fertilization, the first cell division is completed A) within a few seconds. B) within the hour. C) about 6 hours later. D) in 12 hours. E) more than a day later.
e
As a person ages, A) the skin becomes more elastic. B) lung tissue becomes more elastic. C) peristalsis and muscle tone decrease. D) all hormone levels decrease. E) peristalsis and muscle tone decrease and some hormone levels decrease.
e
Contact of a sperm with the oocyte membrane causes A) oocyte activation. B) completion of the second meiosis. C) extrusion of the second polar body. D) membrane fusion. E) All of the answers are correct.
e
During the ________ stage, the placenta is expelled from the uterus. A) expulsion B) dilation C) crowning D) exit E) placental
e
If both parents are heterozygous dominant for a trait, what is the probability of an offspring inheriting the recessive trait? A) 10% B) 25% C) 50% D) 75% E) 100%
e
Polyspermy results in A) twins. B) fetuses with different fathers. C) haploid individuals. D) chimeric adults. E) a nonfunctional zygote.
e
Progesterone calms the myometrium and prevents contraction. What factors antagonize progesterone and trigger labor and delivery? A) Rising estrogen levels increase sensitivity. B) Rising oxytocin levels lead to uterine contractions. C) distortion of the myometrium D) distortion of the cervix E) All of the answers are correct.
e
The Y chromosome carries information for A) the penis. B) the development of the brain. C) sexual drive. D) fertility ability. E) the development of the testes.
e
The ________ is the portion of the endometrium not in contact with the chorion. A) trophoblast B) allantois C) deciduas capsularis D) decidua functionalis E) decidua parietalis
e
The ________ period extends from birth to 1 month. A) post-embryonic B) post-fetal C) neogen D) zygotic E) neonatal
e
The alternate forms of any one gene are called A) homologous. B) homozygous. C) heterozygous. D) autosomes. E) alleles.
e
The cell that directly results from the fusion of a secondary oocyte and a spermatozoon is called a(n) A) ootid. B) gastrula. C) blastula. D) morula. E) zygote.
e
The endoderm forms A) muscle. B) blood. C) neural tissue. D) skin. E) the urinary bladder.
e
The full set of genetic information in an individual's chromosomes is called A) pleiotype. B) allotype. C) phenotype. D) isotype. E) genome.
e
The hormone that increases the flexibility of the pubic symphysis during pregnancy is A) luteinizing hormone. B) progesterone. C) human chorionic gonadotropin. D) human placental lactogen. E) relaxin.
e
The outer layer of the blastocyst that can penetrate the endometrium is the A) archegonium. B) chorion. C) gastrula. D) blastula. E) trophoblast
e
The placenta is a source of which of the following hormones? A) hCG B) relaxin C) placental lactogen D) progesterone E) All of the answers are correct.
e
Which of the following activities occurs during senescence? A) decrease in the size of some cell populations B) accumulation of mutations C) reduction in immune response D) reduced mitosis in stem cells E) All of the answers are correct.
e
Which of the following are recognized classes of abortion? A) spontaneous B) therapeutic C) induced D) spontaneous and induced E) All of the answers are correct.
e
Which of the following does not occur during pregnancy? A) A woman's respiratory rate and tidal volume increase. B) Maternal blood volume increases. C) Maternal nutrient requirements increase. D) A woman's glomerular filtration rate increases. E) A woman's bladder capacity increases
e
Which of the following is a critical event of the first trimester? A) cleavage B) implantation C) placentation D) embryogenesis E) All of the answers are correct.
e
Which of the following is false concerning the allantois? A) It derives partly from endoderm. B) It projects into the umbilical cord. C) It stores nitrogenous wastes. D) Part will develop as the urinary bladder. E) It acts as the fetal bone marrow.
e
Which of the following is not one of the extraembryonic membranes? A) yolk sac B) amnion C) allantois D) chorion E) umbilical cord
e
The period from 1 month after birth to 1year is known as A) childhood. B) post-fetal. C) neogen. D) infancy. E) neonatal.
d
A 5-6-kg (11-13-lb) infant usually requires about ________ of milk per day. A) 250 ml B) 1.5 quarts C) 100 ml D) 850 ml E) 1 cup
d
During early development, the Y chromosome produces a substance called "testis determining factor" (TDF) that causes the indifferent gonad to become a testis. This would be an example of A) capacitation. B) activation. C) differentiation. D) induction. E) predilection.
d
If fertilization occurs, the ________ is maintained because the embryo secretes ________. A) corpus albicans; human chorionic gonadotrophin B) corpus luteum; luteinizing hormone C) corpus cavernosum; human chorionic gonadotrophin D) corpus luteum; human chorionic gonadotrophin E) corpus albicans; placental prolactin
d
Non-sex chromosomes are called A) homologous. B) homozygous. C) heterozygous. D) autosomal. E) chromatids.
d
Placental functions are concentrated in a disc-shaped area in the endometrium called the A) trophoblast. B) allantois. C) deciduas capsularis. D) decidua basalis. E) decidua parietalis.
d
Polyspermia is prevented by the ________ reaction. A) metabolic B) gamete C) gollumina D) cortical E) polarity
d
Shortly after gastrulation, the body and organs of the embryo begin to form. This process is called A) cleavage. B) implantation. C) placentation. D) embryogenesis. E) germination.
d
The extraembryonic membrane that forms the fetal portion of the placenta is the A) yolk sac. B) amnion. C) allantois. D) chorion. E) decidua.
d
The hormone called the hormone of pregnancy, inhibiting uterine contractions, is A) hCG. B) relaxin. C) placental lactogen. D) progesterone. E) All of the answers are correct.
d
The part of the endometrium that covers the implanted embryo and lacks chorionic villi is the A) decidua parietalis. B) decidua albicans. C) decidua functionalis. D) decidua capsularis. E) decidua basalis.
d
