Chapter 27 Review (some questions from 26)

If an individual carries a pair of alleles that are the same, the individual is ________ for the trait.

homozygous

A zygote whose genotype is XY will develop as a

male

________ is the process of sloughing off the old functional layer of the endometrium.

menstruation

the mesoderm forms

muscle

the ectoderm forms______

neural tissue

the surge in luteinizing hormone secreted by the corpus luteum is _____.

ovulation

Stretching of the cervix causes an increase in the blood levels of

oxytocin

The breasts are attached to the chest superficial to the ________ muscle.

pectoralis major

The traits of an individual controlled by his or her genotype are his or her

phenotype

forms the interface between the embryonic/fetal system and the maternal system.

placenta

what are the functions of the gonads?

produce and store gametes

The principal hormone secreted by the corpus luteum is

progesterone

A ________ is used to show all possible combinations of genes that can result from a given parental cross.

punnett square

The hormone that increases the flexibility of the pubic symphysis during pregnancy is

relaxin

Follicle-stimulating hormone (FSH)

stimulates spermatogenesis and stimulates maturation of primordial follicles in the ovary.

A fetus undergoes its largest absolute weight gain during which trimester?

third trimester

the endoderm forms

urinary bladder

fertilization of an ovum usually takes place in the _____

uterine tube

Fertilization is complete when which of the follow occurs? A) oocyte activation B) pronucleus formation C) spindle formation D) amphimixis and cleavage

D) amphimixis and cleavage

Which chemicals are primarily responsible for initiating contractions of true labor? A) prolactin B) progesterone C) relaxin and inhibin D) estrogens and oxytocin stimulate the production of prostaglandins E) LH and oxytocin

D) estrogens and oxytocin stimulate the production of prostaglandins

attachment to and penetration of the endometrium by the blastocyst is referred to as

implantation

the production of milk is called _____

lactation

If an individual carries two different alleles for the same trait, the individual is ________ for the trait. A) homologous B) homozygous C) heterozygous D) autosomal E) polygenic

C) heterozygous

A blastocyst is a(n) A) extra-embryonic membrane. B) solid ball of cells. C) hollow ball of cells. D) portion of the placenta. E) origin of the urinary bladder.

C) hollow ball of cells.

The period of gestation that is characterized by the largest fetal weight gain and fat deposition is the ________ trimester. A) first B) second C) third

C) third

During gastrulation, A) the blastomeres fuse. B) the placenta penetrates the endometrium. C) three germ layers are formed. D) blastomeres form. E) the neural tube closes.

C) three germ layers are formed.

Define organogenesis.

Organogenesis is the process of organ formation.

How can you tell that the karyotype shown here is male?

The 23rd pair of chromosomes is XY.

A child born with one lone X chromosome will have

Turner's syndrome

The various forms of any one gene are called

alleles

hollow ball of cells is called

blastocyst

The individual cells produced by cleavage are called

blastomeres

The trophoblast has many of the characteristics of ________ cells.

cancer

The process of cell division that divides the cytoplasm of the zygote among blastomeres is called

cleavage

The 3 germ layers of gastrulation are

ectoderm, endoderm, mesoderm

The oval, three-layered sheet produced by gastrulation is called the

embryonic disc

The _____is the inner lining of the uterus

endometrium

A zygote whose genotype is XX will develop as a

female

The ________ is the rounded portion of the uterine body superior to the attachment of the uterine tubes.

fundus

By day 12 of embryonic development, mesoderm begins to form through

gastrulation

A person's original chromosomes and their component genes constitute that person's

genotype

how many chromosomes does a zygote contain?

46

Why does a mother's blood volume increase during pregnancy?

A mother's blood volume increases to accommodate for flow through the placenta.

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) All E) None

A) 1/2

Which of the following is a puberty-related change caused by increased testosterone levels? A) accelerated bone deposition and skeletal growth B) loss of terminal hairs on the face and chest C) replication of skeletal muscle fibers D) thinning of the vocal folds E) decreased erythropoiesis

A) accelerated bone deposition and skeletal growth

The first stage of labor is the ________ stage. A) dilation B) expulsion C) placental

A) dilation

Which of the following hormones is the cause of most puberty-related changes in a female? A) estrogen B) progesterone C) oxytocin D) relaxin E) chorionic gonadotropin

A) estrogen

Embryonic and early fetal development occurs in the ________ trimester. A) first B) second C) third

A) first

The period of gestation when the rudiments of all major organ systems are established is the ________ trimester. A) first B) second C) third

A) first

The placenta is expelled from the uterus during the ________ stage of labor. A) placental B) expulsion C) dilation

A) placental

The placenta is expelled from the uterus during the ________ stage of labor. A) placental B) expulsion C) dilation D) contraction E) afterbirth

A) placental

During implantation, the A) syncytial 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) syncytial trophoblast erodes a path through the endometrium.

Oxygenated blood is carried away from the placenta by the A) umbilical vein. B) umbilical arteries.

A) umbilical vein.

Describe the process that forms the primary germ layers and cite the layer that contributes to nearly all body systems. (Module 27.4A) A) Gastrulation forms the primary germ layers from the embryonic disc. The endoderm contributes to nearly all body systems. B) Gastrulation forms the primary germ layers from the embryonic disc. The mesoderm contributes to nearly all body systems. C) Formation of the primitive streak gives rise to the primary germ layers. The ectoderm contributes to nearly all body systems. D) Formation of the primitive streak gives rise to the primary germ layers. The endoderm contributes to nearly all body systems. E) Gastrulation forms the primary germ layers from the embryonic disc. The ectoderm contributes to nearly all body systems.

B) Gastrulation forms the primary germ layers from the embryonic disc. The mesoderm contributes to nearly all body systems.

Molly is homozygous for the dominant black hair trait. Therefore, A) Molly is a carrier for the black hair trait. B) Molly has black hair. C) Molly's hair color cannot be determined from this information

B) Molly has black hair.

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) determined by interactions among several genes.

The stage of labor during which the fetus emerges from the vagina is called the ________ stage. A) dilation B) expulsion C) placental

B) expulsion

Which hormone stimulates the milk let-down reflex? A) progesterone B) oxytocin C) estrogen D) relaxin E) GnRH

B) oxytocin

During the proliferative phase of the uterine cycle, A) the corpus luteum is forming. B) the functional zone of the endometrium is restored. C) the fertilized ovum implants. D) the uterine glands enlarge. E) menses occurs.

B) the functional zone of the endometrium is restored.

Deoxygenated blood is carried to the placenta by the A) umbilical veins B) umbilical arteries

B) umbilical arteries

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 lacunae. D) form a capillary network in the trophoblast. E) increase in size and penetrate the blastocyst.

C) break down and form lacunae.

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) form the embryo.

List the major changes that occur in maternal systems during pregnancy. A) decreased respiratory rate and tidal volume, decreased blood volume, increased GFR and nutrient requirements, increases in the size of the uterus and mammary glands B) increased immune function, increased heart rate and blood pressure, decreased nutrient requirements and decreased thermoregulation C) decreased immune function, decreased heart rate and blood pressure, decreased blood volume and GFR, and decreased respiratory rate and tidal volume D) increased respiratory rate and tidal volume, increased blood volume and GFR, increased nutrient requirements, and increases in the size of the uterus and mammary glands E) increased respiratory rate and tidal volume, decreased nutrient requirements, decreased blood volume and GFR, and decreased size of the uterus and mammary glands.

D) increased respiratory rate and tidal volume, increased blood volume and GFR, increased nutrient requirements, and increases in the size of the uterus and mammary glands

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) migration of ectodermal cells to form the mesoderm.

After 3 days, a pre-embryo becomes a solid ball of cells known as a A) chorion. B) blastomere. C) lacuna. D) morula. E) blastocyst.

D) morula.

The embryonic heart starts beating as blood begins to flow through chorionic vessels at approximately ________ of development. A) day 3 B) day 12 C) week 2 D) week 3 E) the second trimester

D) week 3

Contact of a sperm with the oocyte membrane does not cause A) oocyte activation. B) completion of the second meiosis. C) formation of the second polar body. D) membrane fusion. E) a decrease in calcium released from the oocyte.

E) a decrease in calcium released from the oocyte.

All of the following occur during pregnancy except 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) a woman's bladder capacity increases.

Endoderm + mesoderm = which extra-embryonic membrane(s)? A) chorion B) amnion C) allantois D) yolk sac E) both yolk sac and allantois

E) both yolk sac and allantois

Which of the following does not occur during the first trimester? A) cleavage B) implantation C) separation of blastomeres to form monozygotic twins D) gastrulation E) organs become functional

E) organs become functional

Progesterone calms the myometrium and prevents contraction. What factor does not 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) relaxation of the cervix

E) relaxation of the cervix