Chapter 29 Development
Ectoderm is to ________ as mesoderm is to ________. muscle tissue; neural tissue neural tissue; muscle tissue mesoderm; endoderm cardiovascular system; neural tissue neural tissue; epithelial tissue
neural tissue; muscle tissue
Which of these pairs of terms is mismatched? third trimester - largest size gain first trimester - formation of trachea and lungs first trimester - placentation second trimester - embryogenesis
second trimester - embryogenesis
Which of the following is not part of oocyte activation? release of calcium ion from smooth ER membrane depolarization influx of sodium iondischarge of exocytotic vesicles adjacent to the oocyte membrane softening of the zona pellucida
softening of the zona pellucida
Which of the following oocyte processes is NOT activated by sperm penetration? completion of meiosis IImembrane depolarization discharge of exocytotic vesicles softening of the zona pellucida
softening of the zona pellucida
Shortly after gastrulation, the body and organs of the embryo begin to form. This process is called cleavage. placentation. germination. embryogenesis. implantation.
embryogenesis.
The process by which a viable embryo is formed is called morphogenesis. blastogenesis. embryogenesis. gametogenesis. organogenesis.
embryogenesis.
Which embryonic germ layer forms the linings of the respiratory and digestive tracts? ectoderm trophoderm endoderm epiderm mesoderm
endoderm
Which of the given cells represents the earliest stage after fertilization? A B C D
A
Which of the images shows the third week of gestation? A B C D
A
Which of the labels in the figure indicates the growing population of mesoderm cells? A B C D
A
Identify the stage labeled "8." early morula trophoblast blastomere advanced morula zygote
advanced morula
The hollow cavity within the blastocyst is the blastocoele. blastula. gastrula. ootid. trophoblast.
blastocoele.
Blood flows from the fetus to the placenta through paired uterine arteries. iliac veins. umbilical arteries. uterine veins. umbilical vein.
umbilical arteries.
The ________ is formed by the allantois, blood vessels, and yolk sac. umbilical cord chorioallantoic membrane trophoblast amnion chorion
umbilical cord
Which of the following is not one of the extraembryonic membranes? allantois umbilical cord yolk sac amnion chorion
umbilical cord
Oxygenated blood from the placenta returns to the fetus in the allantois. umbilical arteries. umbilical vein. umbilical capillaries. decidua capsularis.
umbilical vein
Sperm cannot fertilize an oocyte until they undergo capacitation.are in the vagina for 3 days. undergo meiosis. are activated by sustentacular cells of the vagina. lose their flagellum.
undergo capacitation.
The extraembryonic membrane that forms blood is the allantois. decidua. amnion. yolk sac. chorion.
yolk sac.
The primary nutrient source for early embryonic development that later becomes an important site for blood formation is the yolk sac. placenta. amniotic fluid. basal decidua. umbilical vein.
yolk sac.
The cell that directly results from the fusion of a secondary oocyte and a single sperm is called a(n) ootid. gastrula. zygote. blastula. morula.
zygote.
________ are nearly identical cells that are produced by early cleavages. Blastomeres Gastrulas Blastulas Morulas Amnions
Blastomeres
Which of the following describes maternal and paternal genotypes in this Punnett square of a trait that shows strict dominance? Both parents are heterozygous. The father is recessive, and the mother is dominant. The mother is heterozygous, and the father is homozygous recessive. Both parents are homozygous.
Both parents are homozygous.
Uterine contractions that are irregular and brief that occur toward the end of gestation are called parturition. dilation. true labor. Braxton-Hicks. expulsion.
Braxton-Hicks.
Which extraembryonic membrane partially originates from tissue that is not part of the three germ layers? Amnion Chorion Allantois Yolk Sac
Chorion
Which of the following statements concerning development is false? Differences in a cell's cytoplasmic makeup affect the cell's genetic activity. Cells release molecules that affect the developmental process of neighboring cells. Each blastomere in the blastocyst receives exactly the same cytoplasmic composition. The developing oocyte receives molecules that affect development from the surrounding granulosa cells. The term induction refers to the chemical interplay between developing cells.
Each blastomere in the blastocyst receives exactly the same cytoplasmic composition.
Which of the following is NOT a placental factor involved in initiating labor? Fetal pituitary release of oxcytocin increases. The sensitivity of the smooth muscle cells of the myometrium is increased. Relaxin secretion increases. Estrogen production accelerates.
Fetal pituitary release of oxcytocin increases.
Which of the following best summarizes the difference between genotype and phenotype? Genotype refers to all of the genes individuals inherit, and phenotype refers to the genes they make on their own. Genotype refers to the gene alleles that one has, and phenotype refers to the trait that is expressed in response to those alleles. Genotype refers to the DNA one has, and phenotype refers to the RNA he or she inherits. Genotype refers to the genes one has, and phenotype refers to the alleles that person has.
Genotype refers to the gene alleles that one has, and phenotype refers to the trait that is expressed in response to those alleles.
Which of the following does not occur at puberty? FSH levels rise. Levels of sex hormones rise. GnRH levels decline. Gametogenesis begins. Secondary sexual characteristics begin to develop.
GnRH levels decline.
Which of the following is false concerning the allantois? It projects into the umbilical cord. It acts as the fetal bone marrow. It stores nitrogenous wastes. Part will develop as the urinary bladder. It derives partly from endoderm.
It acts as the fetal bone marrow.
Which of the following is true about genetic mutation? It is a change in the DNA base sequence. It is rarely passed on to other cells. It is defined as a change in a person's phenotype. Mutations always have a negative impact.
It is a change in the DNA base sequence.
Which of the following is true concerning the onset of labor contractions? Prostaglandins suppress contractions. Labor contractions work through positive feedback to help expel the fetus. Oxytocin from the mother makes the fetus irritable and active. Progesterone is a major stimulus of labor.
Labor contractions work through positive feedback to help expel the fetus.
During development, the placenta secretes several hormones, including progesterone and estrogen. But what would happen if the fetus is male? Placental secretion of estrogen and progesterone would cause the male fetus to become feminized. Placental secretion of estrogen and progesterone would cause the male fetus to be sterile. Placental secretion of estrogen and progesterone would have no effects on the developing fetus. Placental secretion of estrogen and progesterone would cause the male fetus to develop smaller than normal external genitalia.
Placental secretion of estrogen and progesterone would have no effects on the developing fetus.
An infant born ________ prematurely has a good chance of survival. 3 months 5 months 6 months 1.5 months 4 months
1.5 months
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? 1/2 3/4 1/8 1/4 100 (all)
1/2
If one parent is homozygous for a trait that exhibits simple dominance, and the other parent is heterozygous for that trait, their offspring will have a __________ chance of possessing that trait. 100% 50% 25% 0%
100%
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? 100% albino 75% normal skin pigment and 25% albino 50% normal skin pigment and 50% albino 25% normal skin pigment and 75% albino 100% normal skin pigment
100% normal skin pigment
How many chromosomes do human gametes contain? 23 46 92 12 6
23
How many chromosomes do human somatic cells contain? 46 92 12 6 23
46
By the end of gestation, maternal blood volume normally increases by almost ________ percent. 100 20 80 25 50
50
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? 75% homozygous type O 100% type A 50% type A, 50% type O 100% type O 75% heterozygous type A
50% type A, 50% type O
If both mother and father are heterozygous for a trait showing simple dominance, what is the probability that one of their future children will show that trait? 25 percent zero percent 100 percent 75 percent
75 percent
Which of the following does not occur during pregnancy? A woman's respiratory rate and tidal volume increase. A woman's bladder capacity increases. Maternal blood volume increases. A woman's glomerular filtration rate increases. Maternal nutrient requirements increase.
A woman's bladder capacity increases.
If a woman is having trouble with kidney function, which of the following consequences to the mother's physiology could the developing fetus face? Not enough renin or erythropoietin would be secreted to increase blood volume to necessary levels. The maternal glomerular filtration rate would remain too low, potentially producing a toxic environment within the placenta. The development of preeclampsia could progress to eclampsia, threatening both mother and fetus. All are conditions harmful to the maternal physiology that could potentially harm the developing fetus.
All are conditions harmful to the maternal physiology that could potentially harm the developing fetus.
Which of these hormones is/are secreted by the placental tissues? progesterone human chorionic gonadotropin (hCG) placental lactogen All of the listed hormones are secreted by placental tissues.
All of the listed hormones are secreted by placental tissues.
Which of these processes occurs after oocyte activation and the completion of meiosis II? The nucleus of the sperm cell swells. The nuclear material within the ovum reorganizes into a female pronucleus. The head, neck, and middle pieces of the sperm cell break down. All of the listed processes occur after oocyte activation and the completion of meiosis II.
All of the listed processes occur after oocyte activation and the completion of meiosis II.
Which membrane becomes an organ in the developing fetus? Yolk Sac Allantois Chorion Amnion
Allantois
An individual has two of the same alleles for a gene for eye color. One of her eyes is deep blue, and the other is a lighter blue. Which of the following is true? She is homozygous for that gene. She is heterozygous for that gene. She is homozygous for the phenotype. She is homozygous for that gene, but heterozygous for the phenotype.
She is homozygous for that gene.
Explain why this is a karyotype of a male and not a female. (Figure 29-14) The 23rd chromosome is a Y chromosome. The 23rd pair of chromosomes are an XX. There are 24 pairs of chromosomes. There are 22 pairs of chromosomes. The 23rd pair of chromosomes are an XY.
The 23rd pair of chromosomes are an XY.
Which of the following statements about the first trimester is false? The events that occur during the first trimester are very complex. During this trimester, cleavage, implantation, placentation and embryogenesis occur. It consists of 10 developmental weeks. Only about 40 percent of conceptions survive the first trimester. The fetus gains the most weight during the first trimester.
The fetus gains the most weight during the first trimester.
The smooth muscle of the myometrium undergoes which of the following changes during gestation? increased sensitivity to oxytocin spontaneous contractions tremendous stretching by the growth and increase in fetal weight The myometrium undergoes all of the listed changes during gestation.
The myometrium undergoes all of the listed changes during gestation
Which of these statements about monozygotic twins is FALSE? They are identical. They may form when the inner cell mass splits. They form when blastomeres fuse in the pre-embryonic stage. They may form when there is a complete separation during cleavage.
They form when blastomeres fuse in the pre-embryonic stage.
Which extraembryonic membrane is responsible for red blood cell production during early development? Amnion Allantois Chorion Yolk Sac
Yolk Sac
Polyspermy results in Polyspermy results infetuses with different fathers. chimeric adults. a nonfunctional zygote. haploid individuals. twins.
a nonfunctional zygote.
In simple autosomal inheritance, phenotypic characters are determined, or controlled, by the genes on the Y chromosome. multiple alleles. the action of a single gene. a single pair of alleles. regulator genes on a different chromosome.
a single pair of alleles.
After fertilization, the first cell division is completed within the hour. in 12 hours. within a few seconds. about 6 hours later. about 30 hours later.
about 30 hours later.
How many days after fertilization will it take the pre-embryo to reach the point indicated by the red arrow? 1 day 2-3 days about 5 days 7-10 days
about 5 days
The developmental period heralded by the onset of puberty is known as early childhood. pre-teen. teenage years. post-infancy. adolescence.
adolescence.
The infancy stage of life is considered to be over at 1 month. 6 months. 18 months. age 2.3 months
age 2.
The umbilical cord contains the yolk sac, the placental blood vessels and the chorionic villi. allantois. amnion. chorion. decidua.
allantois.
The alternate forms of any one gene are called alleles. homozygous. heterozygous. autosomes. homologous.
alleles.
A pregnant female does not know if her child has Down syndrome. What technique would enable her to find out if she is carrying a child with Down syndrome? Pap smear amniocentesis cheek cell swab There is no test to determine this syndrome.
amniocentesis
In ________, a sample of amniotic fluid is removed and the fetal cells it contains are analyzed. amniocentesis chorionic villus sampling amniosis paracentesis thoracentesis
amniocentesis
During the second trimester, the mesoderm on the outer surface of the amnion contacts the mesoderm on the inner surface of the chorion and fuse to form the ________ membrane. amniochorionic embryonic cervical umbilical syncytial
amniochorionic
Identify the structure labeled "6." basal decidua umbilical cord amnion parietal decidua placenta
amnion
The extraembryonic membrane that forms a fluid-filled sac is the decidua. amnion. yolk sac. chorion. allantois.
amnion.
The fetus develops within a membranous cavity called the __________. allantois amniotic cavity chorion decidua parietalis
amniotic cavity
A space opens within the inner cell mass that will form the chorion. lacunae. allantois. blastocoele. amniotic cavity.
amniotic cavity.
The separation between the inner cell mass and the trophoblast forms a fluid-filled chamber called the placenta. allantois. chorion. amniotic cavity. yolk sac.
amniotic cavity.
Senescence involves all of the following EXCEPT __________. .an increased stem cell mitotic rate a weaker immune response a decrease in glomerular filtration rate a loss of elasticity in tissues
an increased stem cell mitotic rate
Non-sex chromosomes are called autosomal. chromatids. homozygous. homologous. heterozygous.
autosomal
Identify the structure labeled "2." basal decidua placenta chorion amnion endometrium
basal decidua
Placental functions are concentrated in a disc-shaped area in the endometrium called the capsular decidua. trophoblast. allantois. basal decidua. parietal decidua
basal decidua.
Where in the embryo does mesoderm first appear? around the trophoblast above the epiblast in the chorionic villi between the cell layers of the inner cell mass within the blastocoele
between the cell layers of the inner cell mass
Identify the stage labeled "12." trophoblast late morula blastocyst early morula zygote
blastocyst
Implantation of the __________ occurs about seven days after __________. blastocyst; fertilization zygote; fertilization zygote; ovulation blastocyst; ovulation
blastocyst; fertilization
Identify the structures labeled "6." polar bodies cytotrophoblast blastomeres syncytiotrophoblast trophoblast
blastomeres
The almost identical cells produced by cleavage divisions are called blastomeres. telomeres. centromeres. myosomes. somal cells.
blastomeres.
Which of the following events does NOT occur during the third trimester of prenatal development? accumulation of adipose tissue organ systems fully functional blood formation begins in the liver large weight gain
blood formation begins in the liver
The trophoblast induces endometrial capillaries to __________. invade the inner cell mass penetrate the chorion invade the trophoblast break down and form lacunae
break down and form lacunae
Under the influence of the trophoblast, maternal blood vessels in the endometrium break down and form sinuses or lacunae. attach to the inner cell mass. increase in size and penetrate the blastocyst. form a capillary network in the trophoblast.disappear.
break down and form sinuses or lacunae.
Identify the structure labeled "8." amnion placenta capsular decidua basal decidua chorion
capsular decidua
The part of the endometrium that covers the implanted embryo and lacks chorionic villi is the albicans decidua. capsular decidua. functional decidua. parietal decidua. basal decidua.
capsular decidua.
In polygenic inheritance, phenotypic characters are determined by multiple copies of a single gene. determined by a double pair of alleles. determined by the genes on the Y chromosome. determined by interactions among several genes. always controlled by genes on the same chromosome.
determined by interactions among several genes.
The gradual modification of an organism from conception to maturity is called __________. fertilization differentiation development embryonic development
development
The gradual modification of anatomical structures and physiologic characteristics from fertilization to maturity is termed ontogeny transformation gametogenesis disablement development
development
The formation of different types of cells required in development, or ________, occurs through selective changes in genetic activity. deployment differentiation cupellation gametogenesis phylogeny
differentiation
The process that results in the formation of different cell types occurring through selective changes in genetic activity that causes some genes to be turned off, while others are turned on is called __________. development conception fertilization differentiation
differentiation
Which of these is NOT a stage in development? embryonic development prenatal development differentiation postnatal development
differentiation
The first stage of labor is the ________ stage. neonate decidual placental dilation expulsion
dilation
Which of the following places the stages of labor in the correct order?expulsion, dilation, placental dilation, expulsion, placental dilation, placental, expulsion placental, expulsion, dilation placental, dilation, expulsion
dilation, expulsion, placental
A ________ allele will always be expressed regardless of what the other allele happens to be. homologous dominant recessive maternal homocentric
dominant
During gastrulation the three germ layers are formed. Which germ layer will ultimately give rise to all of the neural system? mesoderm endoderm ectoderm allantois
ectoderm
The epidermis and accessory structures of skin form from which germ layer? mesoderm epiderm ectoderm trophoderm endoderm
ectoderm
Which embryonic germ layer forms the brain and spinal cord? ectoderm trophoderm endoderm mesooderm epiderm
ectoderm
In ________, implantation occurs somewhere other than in the uterus. placenta previa ectopic pregnancy hydramnios abortion spontaneous abortion
ectopic pregnancy
In a(n) ________, an incision is made in the perineal musculature. episiotomyl umbar puncture crowning peritoneal cut epidural
episiotomy
The stage of labor during which the fetus emerges from the vagina is called the ________ stage. expulsion dilation emergence fetal placental
expulsion
What term refers to the fusion of two haploid gametes, each containing 23 chromosomes, producing a zygote that contains 46 chromosomes? fertilization ovulation differentiation cleavage
fertilization
The neonatal period extends until breast feeding stops. for the first 24 hours of life. for the first six months. until the first birthday. for the first month of life.
for the first month of life
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.
form the embryo.
What is the developmental fate of "9"? forms the placenta forms the chorion forms the embryo forms the parietal decidua forms the trophoblast
forms the embryo
At what stage of embryogenesis do the three germ layers form? extraembryonic stage gastrulation neural tube formation blastocyst
gastrulation
The full set of genetic information in an individual's chromosomes is called isotype. genome. allotype. phenotype. pleiotype.
genome.
The term ________ refers to the time spent in prenatal development. micturition transformation cleavage parturition gestation
gestation
Increased release of which of these hormones triggers the onset of puberty? follicle-stimulating hormone (FSH) gonadotropin-releasing hormone (GnRH) sex hormones luteinizing hormone (LH)
gonadotropin-releasing hormone (GnRH)
Immediately after birth, a newborn's health is assessed by an Apgar score. Which of the following is not part of the Apgar assessment?breathing hearing heart rate muscle tone skin color
hearing
If an individual carries two different alleles for the same trait, the individual is ________ for the trait. polygenic homozygous autosomous homologous heterozygous
heterozygous
If an individual has a dominant allele on one chromosome but a recessive allele at the same position on the homologous chromosome, he or she is genetically __________ for the trait. heterozygous abnormal homozygous homologous
heterozygous
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.
hollow ball of cells.
If an individual carries a pair of alleles that are the same, the individual is ________ for the trait. homozygous heterozygous polygenic autosomous homologous
homozygous
The presence of a recessive gene can be detected (seen) only if the individual is homozygous recessive .homozygous dominant. heterozygous dominant. heterozygous recessive. epistatic recessive.
homozygous recessive.
Sperm release ________ to break down the bonds between adjacent follicle cells surrounding the oocyte. hyaluronidase glucose relaxin calcium zonal inhibiting proteins
hyaluronidase
The uterine epithelium is broken down by the enzyme, relaxin. urase. proteoglycan. acrosin. hyaluronidase.
hyaluronidase.
Identify the process occurring at the structure labeled "13." gastrulation fertilization implantation migration ovulation
implantation
The penetration of the endometrium by the blastocyst is referred to as embryogenesis. implantation. fertilization. cleavage. placentation.
implantation.
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 differentiation. induction. capacitation. predilection. activation.
induction
The period from 1 month after birth to 1 year is known as neonatal. post-fetal. infancy. childhood. neogen.
infancy.
The transfer of genetically determined characteristics from generation to generation is termed phylogeny inheritance differentiation development maturity
inheritance.
The entire set of chromosomes of an individual can be visualized on a karyotype. locus. Punnett square. map. genotype.
karyotype.
What maternal organ is indicated by the red arrow? stomach liver lung spleen
liver
A gene's position on a chromosome is called a locus. map. recombinant. karyotype. genome.
locus
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 high levels of HCG. unresponsive smooth muscle around the mammary glands. low levels of estrogen. low levels of oxytocin. low levels of progesterone.
low levels of oxytocin.
The placenta is a source of all of the following hormones, except placental lactogen. relaxin. luteinizing hormone. hCG. progesterone.
luteinizing hormone.
If a sperm carrying the "Y" chromosome fertilizes the ovum, the resulting offspring will be Rh positive blood type. fraternal twins. female. male. haploid.
male
What is found in the area indicated by the arrow? maternal blood yolk fetal blood amniotic fluid
maternal blood
What is the name of the third germ layer that forms during gastrulation? ectoderm mesoderm embryonic disc endoderm primitive streak
mesoderm
Which embryonic germ layer forms connective tissues such as bone and cartilage? trophoderm mesooderm endoderm ectoderm epiderm
mesooderm
The region known as the primitive streak is the site of migration of mesodermal cells to form the endoderm. endoderm formation. migration of ectodermal cells to form the mesoderm. amnion formation. ectoderm formation.
migration of ectodermal cells to form the mesoderm.
Twins that occur when blastomeres separate are called monozygotic. dizygotic. blastulatory. zygoblastic. fraternal.
monozygotic
After three days of cleavage divisions, the pre-embryo is a solid ball of blastomeres. What is the name of the pre-embryo at this stage? morula blastocyst inner cell mass zona pellucida
morula
The solid ball of cells that has been likened to a mulberry is called a blastocyst. morula. blastula. gastrula. chorion.
morula.
The mesoderm forms the brain. respiratory epithelium. epidermis. muscle. the lining of the digestive tract.
muscle.
The ectoderm forms the lining of the digestive tract. neural tissues. muscle. blood. the urinary system.
neural tissues.
The site where fertilization normally occurs is in the fimbrae. outer one-third of the uterine tube. uterine wall near the fundus. union of the vagina and uterus. cervix.
outer one-third of the uterine tube.
Fertilization stimulates the oocyte to enter meiosis II and the fertilized oocyte is called a(n) primary oocyte. ovum. polar body. oogonium. secondary oocyte.
ovum
The endocrine organ at the end of the arrow releases __________ in response to the infant sucking on the nipple. oxytocin prolactin estrogen progesterone
oxytocin
What hormones stimulate and increase the excitability of the myometrium? (Figure 29-10) oxytocin and prostaglandins prolactin and prostaglandins estrogen and prostaglandins oxytocin and progesterone estrogen and progesterone
oxytocin and prostaglandins
Mammary gland development requires a combination of all of the following hormones, except placental prolactin. oxytocin. estrogen. prolactin. human placental lactogen.
oxytocin.
Stretching of the cervix causes an increase in the blood levels of estrogen. chorionic gonadotropin. relaxin. progesterone. oxytocin.
oxytocin.
The ________ is the portion of the endometrium not in contact with the chorion. trophoblast parietal decidua capsular decidua functional decidua allantois
parietal decidua
The goal of labor is childbirth, also termed abortion. senescence. parturition. development. gestation.
parturition.
As a person ages, the skin becomes more elastic. lung tissue becomes more elastic. all hormone levels decrease. peristalsis and muscle tone decrease. peristalsis and muscle tone decrease and some hormone levels decrease.
peristalsis and muscle tone decrease and some hormone levels decrease.
Are environmental factors more likely to affect genotype or phenotype? phenotype They can affect both equally. genotype Environmental factors can't affect either one.
phenotype
The traits of an individual controlled by his or her genotype are his or her isotype. genotype. phenotype. allotype. pleiotype.
phenotype.
During embryonic development, which structure temporarily takes on the function of the lungs? yolk sac placenta endometrium myometrium
placenta
Identify the structure labeled "4." basal decidua endometrium chorion placenta amnion
placenta
The last stage of labor is __________. loss of amniotic fluid placental gestation dilation
placental
The processes that occur in the embryonic period are cleavage and placentation. placentation and embryogenesis. implantation and embryogenesis. implantation and placentation. cleavage and implantation.
placentation and embryogenesis.
Height is not expressed by a simple dominant and recessive allele. This type of inheritance is termed incomplete dominance. simple inheritance. polygenic inheritance. codominance. strict dominance.
polygenic inheritance.
Which of the following is least likely to result in a genetic mutation? radiation drugs poor health errors in DNA replication
poor health
During gestation, contraction of the myometrium is inhibited by ________, produced by the corpus luteum. oxytocin progesterone inhibin estrogen prostaglandins
progesterone
Which of the following hormones does NOT play a role in initiating labor contractions? estrogen oxytocin progesterone prostaglandin
progesterone
The hormone called the hormone of pregnancy, inhibiting uterine contractions, is hCG. relaxin. placental lactogen. luteinizing hormone. progesterone.
progesterone.
A patient comes in the clinic expressing concern over changes in her body. She says she has been experiencing axillary and genital hair growth, breast growth, acne and she is going through a growth spurt. You reassure her these are all a normal part of maturation and inform her that she has begun menarche. menopause. peri-menopause. prenatal development. puberty.
puberty.
Adolescence begins at the period of sexual maturity called gestation. senescence. menopause. puberty. postnatal.
puberty.
A ________ allele is expressed only when homozygous. homocentric dominant maternal recessive homologous
recessive
The hormone that increases the flexibility of the pubic symphysis during pregnancy is human chorionic gonadotropin. relaxin. luteinizing hormone. progesterone. human placental lactogen.
relaxin.
The period of gestation when organs and organ systems complete most of their development and the fetus looks distinctly human is the ________ trimester. first second third
second
The 23rd set of chromosomes determines body characteristics. sex drive. sex. blood type. characteristics of the brain.
sex
Which of the following is NOT a disorder that would be associated with the pair of chromosomes shown? sickle cell anemia some types of hemophilia red-green color blindness Duchenne's muscular dystrophy
sickle cell anemia
What types of inheritance are involved in the following phenotypes-nearsightedness, normal vision, and red-green color blindness? simple inheritance; simple inheritance; sex-linked inheritance sex-linked inheritance; polygenic inheritance; polygenic inheritance polygenic inheritance; sex-linked inheritance; sex-linked inheritance simple inheritance; polygenic inheritance; sex-linked inheritance polygenic inheritance; simple inheritance; polygenic inheritance
simple inheritance; simple inheritance; sex-linked inheritance
The prostaglandins produced in the endometrium stimulate smooth muscle contractions. initiate the release of oxytocin for parturition. initiate secretory activity in the mammary glands. promote breast development. stimulate the milk let-down reflex.
stimulate smooth muscle contractions.
The uterine epithelium is broken down by which structure of the blastocyst? blastocoele amnion cytotrophoblast syncytiotrophoblast allantois
syncytiotrophoblast
The embryo becomes a fetus at the end of the eighth week. the end of the first week. the end of the second trimester. the end of the second week. the end of the third trimester.
the end of the eighth week.
The developmental period that is the period of all embryological and early fetal development is the first trimester. the third trimester. the second trimester. adolescence. infancy.
the first trimester
All of the following changes occur during puberty, except the hypothalamus decreases its production of GnRH. FSH levels increase. LH levels increase. growth rate increases. gamete formation begins.
the hypothalamus decreases its production of GnRH.
During amphimixis... the male and female pronuclei fuse. the ovum finishes meiosis II. gametes are formed. sperm become haploid. meiosis occurs.
the male and female pronuclei fuse
The zygote forms when __________. sperm penetrates the oocytethe male and female pronuclei fuse the spermatozoan contacts the oocytethe female pronucleus completes meiosis II
the male and female pronuclei fuse
The endoderm forms blood. skin. muscle. the urinary bladder. neural tissue.
the urinary bladder.
The period of gestation that is characterized by rapid fetal growth and fat deposition is the ________ trimester. first second third
third
The period of gestation that is characterized by rapid growth and fat accumulation is the __________ trimester. third postnatal first second
third
During gastrulation, cells from the hypoblast move to the epiblast. the neural tube closes. the blastomeres fuse. the placenta penetrates the endometrium. three germ layers are formed.
three germ layers are formed.
The human gestation period consists of two trimesters of 2 months each. three trimesters of 3 months each. two trimesters of 1 month each. fertilization and one trimester. three trimesters of 1 month each.
three trimesters of 3 months each.
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.
trophoblast erodes a path through the endometrium.
The outer layer of the blastocyst that can penetrate the endometrium is the blastula. archegonium. gastrula. trophoblast. chorion.
trophoblast.
What is the name and function of the outer cell layer of a blastocyst? blastomere; implant into the uterine wall inner cell mass; become the yolk sac blastocoele; form the embryo trophoblast; provide nutrients morula; become the amniotic fluid
trophoblast; provide nutrients
Fraternal twins result from one zygote that splits into two zygotes. a blastula that splits into two blastulas. one egg that is fertilized by two different sperm. two eggs fertilized by one sperm cell. two different zygotes.
two different zygotes.
Identify the structure labeled "3." capsular decidua umbilical cord placenta yolk sac basal decidua
umbilical cord
Regarding maternal systems, which of these does NOT increase during pregnancy? urinary bladder capacity glomerular filtration rate (GFR) blood volume respiratory rate
urinary bladder capacity
________ is the medical specialty that focuses on postnatal development from infancy to adolescence. Pediatrics Orthopedics Geriatrics Psychiatrics Obstetrics
Pediatrics
Which of the following events happens during the expulsion stage? The amniochorionic membrane ruptures. Infrequent contractions increase in frequency and intensity. The placenta is ejected. Contractions reach maximum intensity, occur in two- to three-minute intervals, and last a full minute.
Contractions reach maximum intensity, occur in two- to three-minute intervals, and last a full minute.
Which of the following is not included in the neonatal period? Neonates demonstrate hourly to daily shifts in body temperature. Neonatal metabolic rate per unit of body weight is approximately twice that of adults. Neonatal heart rate and respiratory rates are much lower than those of adults because the baby is so much smaller. Neonatal fluid requirements are much greater than those of adults.
Neonatal heart rate and respiratory rates are much lower than those of adults because the baby is so much smaller
Nicole has the following genotype: Gene 1: Aa Gene 2: BB Gene 3: cc Based on this, which of the following statements is correct? Nicole is homozygous for genes 1 and 2. Nicole is homozygous only for gene 3. Nicole is heterozygous only for gene 1. Nicole is heterozygous for genes 1 and 3.
Nicole is heterozygous only for gene 1.
Identify the structure labeled "7." chorion amnion basal decidua endometrium placenta
chorion
The extraembryonic membrane that forms the fetal portion of the placenta is the decidua. amnion. yolk sac. chorion. allantois.
chorion.
The mesoderm and the trophoblast combine to form the amnion. inner cell mass. amniotic sac. allantois. chorion.
chorion.
An individual's karyotype shows trisomy 21. This is an example of a recombination error. mutation. chromosomal abnormality. teratogen. translocation.
chromosomal abnormality
The process that divides different portions of the zygote's cytoplasm among blastomeres is called __________. embryogenesis placentation fertilization cleavage
cleavage
The processes that occur in the pre-embryonic period are cleavage and implantation. placentation and embryogenesis. implantation and placentation. implantation and embryogenesis. cleavage and placentation.
cleavage and implantation
The process of cell division that divides the cytoplasm of the zygote among blastomeres is called blastulation. embryogenesis. cleavage. placentation. implantation.
cleavage.
The ABO blood type is an example of which type of inheritance? polygenic inheritance incomplete dominance strict dominance sex-linked codominance
codominance
The clear liquid secreted by the mammary glands before milk production begins is called serum. plasma. colostrum. peritoneal. milk.
colostrum.
The layer of follicle cells that surround the unfertilized egg is called the zona pellucida. tunica follicularis. functional zone. Graafian follicle. corona radiata.
corona radiata.
If fertilization occurs, the ________ is maintained because the embryo secretes ________. corpus luteum; luteinizing hormone corpus cavernosum; human chorionic gonadotrophin corpus albicans; placental prolactin corpus luteum; human chorionic gonadotrophin corpus albicans; human chorionic gonadotrophin
corpus luteum; human chorionic gonadotrophin
Block to polyspermy is prevented by the ________ reaction. gamete gollumina metabolic cortical polarity
cortical
Chromosomal abnormalities associated with recombination errors are more common in females older than age 35. Recombination errors include all of the following EXCEPT __________. deletion translocation defect chromosomal damage crossing over
crossing over
The inner cellular layer of trophoblast that remains intact inside the blastocyst is termed the morula. synctiotrophoblast. cytotrophoblast. lacunae. amnion.
cytotrophoblast.
