Reproductive System Exam Study Guide (Pt. 5)

The almost identical cells produced by cleavage divisions are called blastomeres. ova. morulas. blastocoeles. trophoblasts.

blastomeres.

The individual cells produced by cleavage are called blastocysts. blastocytes. embryos. zygotes. blastomeres.

blastomeres.

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

both yolk sac and allantois

Under the influence of the trophoblast, maternal blood vessels in the endometrium increase in size and penetrate the blastocyst. break down and form lacunae. form a capillary network in the trophoblast. attach to the inner cell mass. disappear.

break down and form lacunae.

The trophoblast has many of the characteristics of ________ cells. infectious cardiac smooth muscle cancer None of the answers is correct.

cancer

Identify the structure labeled "7." amnion chorion myometrium endometrium placenta

chorion

The extra-embryonic membrane that forms the fetal portion of the placenta is the amnion. yolk sac. chorion. allantois.

chorion.

The mesoderm and the cytotrophoblast combine to form the amnion. amniotic sac. chorion. allantois. None of the answers is correct.

chorion.

Identify what process is occurring at the structure labeled "6." ovulation migration cleavage fertilization gastrulation

cleavage

The process of cell division that divides the cytoplasm of the zygote among blastomeres is called blastulation. cleavage. embryogenesis. implantation. placentation.

cleavage.

Which of the following is not part of fertilization? release of acrosomal enzymes amphimixis oocyte activation completion of meiosis II completion of meiosis I

completion of meiosis I

The oval, three-layered sheet produced by gastrulation is called the inner cell mass. embryonic disc. ectoderm. embryo. yolk sac.

embryonic disc.

The inner cell mass of the blastocyst will provide nutrients for early growth. form the placenta. form the morula. form the embryo. form blood vessels of the placenta.

form the embryo.

Completion of cytokinesis does not lead to division of the cytoplasm into two portions. formation of a polar body. initiation of interphase. completion of cleavage. production of two blastomeres.

formation of a polar body.

What is the developmental fate of "9?" forms the chorion forms the embryo dissolves completely forms the trophoblast forms the placenta

forms the embryo

During implantation, the entire trophoblast becomes syncytial. inner cell mass begins to form the placenta. inner cell mass is temporarily deprived of nutrients. maternal blood vessels in the endometrium are walled off from the blastocyst. syncytial trophoblast erodes a path through the endometrium.

syncytial trophoblast erodes a path through the endometrium.

After fertilization, the first cell division is completed in 12 hours. within a few seconds. about 6 hours later. within the hour. more than a day later.

more than a day later.

A pre-embryo that consists of a solid ball of cells is known as what type of structure? (Module 27.3A) blastomere cytotrophoblast morula blastocyst trophoblast

morula

After 3 days, a pre-embryo becomes a solid ball of cells known as a lacuna. blastomere. blastocyst. chorion. morula.

morula.

The mesoderm forms the lining of the digestive tract. muscle. respiratory epithelium. the brain. epidermis.

muscle.

The ectoderm forms neural tissues. the lining of the stomach and small intestine. muscle .the urinary system. blood.

neural tissues.

Which of the following does not occur during the first trimester? organs become functional implantation separation of blastomeres to form monozygotic twins cleavage gastrulation

organs become functional

Identify the structure labeled "4." chorion myometrium endometrium placenta amnion

placenta

Identify the structures labeled "4." polar bodies blastomere morula trophoblast zygotic twins

polar bodies

Name the four extra-embryonic membranes. (Module 27.5A) yolk sac, amnion, allantois, and the chorion amnion, placenta, umbilical stalk, and chorion blastodisc, embryonic disc, cytotrophoblast, and syncytiotrophoblast endoderm, mesoderm, ectoderm, gastroderm yolk sac, amnion, blastocoele, and the trophoblast

yolk sac, amnion, allantois, and the chorion

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

week 3

The extra-embryonic membrane that forms blood cells is the yolk sac. allantois. amnion. chorion.

yolk sac.

Fertilization is complete when which of the follow occurs? formation of blastomeres spindle formation oocyte activation pronucleus formation amphimixis and cleavage

amphimixis and cleavage

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. ectoderm formation. amnion formation.

migration of ectodermal cells to form the mesoderm.

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

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

Describe the chorionic villi. (Module 27.6A) The chorionic villi contain fluid that surrounds and cushions the embryo or fetus. The chorionic villi are structures that extend into the maternal tissues through which maternal blood flows. The chorionic villi form the yolk sac. The chorionic villi forms the umbilical cord. The chorionic villi forms the interface between the embryonic/fetal system and the amniotic fluid.

The chorionic villi are structures that extend into the maternal tissues through which maternal blood flows.

Describe the placenta. (Module 27.5C) The placenta forms the interface between the inner cell mass and the trophoblast. The placenta forms the interface between the embryonic/fetal system and the maternal system. The placenta forms the interface between the blastocoele and the amniotic cavity. The placenta is a layer of cells that surround the yolk sac. The placenta contains fluid that surrounds and cushions the embryo or fetus.

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

Describe the trophoblast. (Module 27.3B) The trophoblast is the cell layer surrounding the blastocyst. The trophoblast is the inner cavity within the blastocyst. The trophoblast is a pre-embryo at the four-cell stage. The trophoblast is a solid ball of cells. The trophoblast is the fluid-filled chamber filled with amniotic fluid.

The trophoblast is the cell layer surrounding the blastocyst.

Identify the stage labeled "8." trophoblast zygote early morula blastomere advanced morula

advanced morula

Identify the structure labeled "6." myometrium placenta umbilical cord chorion amnion

amnion

The extra-embryonic membrane that forms a fluid-filled sac is the amnion. allantois. yolk sac. All of the answers are correct. None of the answers is correct.

amnion.

Identify the structure labeled "5." amniotic cavity placenta endometrium amnion chorion

amniotic cavity

A space opens within the inner cell mass that will form the lacunae. allantois. blastocoele. amniotic cavity. chorion.

amniotic cavity.

By day 12 of embryonic development, mesoderm begins to form through gastrulation. mitosis. embryogenesis. meiosis. None of the answers is correct.

gastrulation.

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

hollow ball of cells.

Attachment to and penetration of the endometrium by the blastocyst is referred to as cleavage. fertilization. embryogenesis. placentation. implantation.

implantation.

Which of the following descriptors regarding the trophoblast is false? spreads into the endometrium absorbs nutrients released by degenerating endometrial glands is derived from the inner cell mass has both a syncytial and cellular component causes maternal blood vessels to break down

is derived from the inner cell mass

All of the following are true of the allantois except it derives partly from mesoderm. part will develop as the urinary bladder. it derives partly from endoderm. it acts as the fetal bone marrow. it projects into the umbilical stalk.

it acts as the fetal bone marrow.

The endoderm forms the urinary bladder. blood. neural tissue. skin. muscle.

the urinary bladder.

During gastrulation, three germ layers are formed. the neural tube closes. blastomeres form. the blastomeres fuse. the placenta penetrates the endometrium.

three germ layers are formed.

Identify the stage labeled "12." morula blastocyst trophoblast zygote cytotrophoblast

trophoblast

Identify the structure labeled "3." yolk sac placenta myometrium amniotic cavity umbilical cord

umbilical cord

The ________ is formed by a portion of the allantois, blood vessels, and remnants of the yolk sac. placenta amnion umbilical cord chorion body stalk

umbilical cord

Which of the following is not one of the extra-embryonic membranes? umbilical cord amnion allantois chorion yolk sac

umbilical cord

Identify the structure connecting the fetus to the placenta, and name the extra-embryonic membrane from which it is derived. (Module 27.6C) umbilical cord; chorion umbilical cord; allantois umbilical cord; amnion yolk sac; chorion yolk sac; allantois

umbilical cord; allantois