Question 1

The formation on endodermal and ectodermal germ layers occurs at ________.&#10;A) fertilization&#10;B) gastrulation&#10;C) cleavage&#10;D) blastula formation

Accepted Answer

The formation of endodermal and ectodermal germ layers occurs during gastrulation, when the blastula undergoes a series of cell movements and rearrangements to form a three-layered structure called the gastrula.

Question 2

Derivatives of the ectoderm include ________.&#10;A) epithelium of the digestive tract&#10;B) epithelium of the respiratory tract&#10;C) nervous tissue&#10;D) none of the above

Accepted Answer

The ectoderm gives rise to the nervous tissue, including the brain and spinal cord. Therefore, option C is correct. Options A and B are incorrect because both the epithelium of the digestive tract and respiratory tract are derived from the endoderm.

Question 3

During which stage of labor is the fetus delivered?&#10;A) expulsion stage&#10;B) placental stage&#10;C) dilation stage&#10;D) gastrula stage

Accepted Answer

The expulsion stage is the final stage of labor where the fetus is delivered through the birth canal.

Question 4

Which of the following is not a germ layer?&#10;A) epiderm&#10;B) endoderm&#10;C) mesoderm&#10;D) ectoderm

Accepted Answer

Epiderm is not a recognized germ layer. The three primary germ layers are endoderm, mesoderm, and ectoderm, which give rise to all the tissues and organs in the body during embryonic development.

Question 5

The placenta is made up of a contribution from mother and fetus. Which portion is from the fetus?&#10;A) umbilicus&#10;B) amnion&#10;C) chorion&#10;D) yolk sac

Accepted Answer

The chorion is the portion of the placenta that develops from the fetal cells. The umbilicus connects the fetus to the placenta, the amnion surrounds the fetus and is part of the fetal membrane, and the yolk sac is important in early fetal development but is not part of the placenta.

Question 6

Which of the following is highly UNLIKELY method of producing a child?&#10;A) embryo transfer&#10;B) ectopic pregnancy&#10;C) in vitro fertilization&#10;D) none of the above

Accepted Answer

An ectopic pregnancy occurs when a fertilized egg implants outside of the uterus, usually in the fallopian tube. It is not a method of intentionally producing a child, and is actually a medical emergency that requires treatment to prevent serious complications. Embryo transfer and in vitro fertilization are both methods of assisted reproduction that can be used to help individuals or couples who are struggling with infertility.

Question 7

What stage of preembryonic development results in a solid ball of nearly identical cells?&#10;A) zygote&#10;B) blastomere&#10;C) blastocyst&#10;D) morula

Accepted Answer

The stage of preembryonic development that results in a solid ball of nearly identical cells is the morula stage. At this stage, the zygote has undergone several rounds of mitotic division and has developed into a ball of approximately 16-32 cells, with no differentiation between the cells yet. The other options are not correct because: 
- A) zygote is the first stage of development after fertilization, when the sperm and egg fuse to form a single cell. 
- B) blastomere refers to any of the cells produced by the early divisions of the zygote. 
- C) blastocyst is a later stage of development, when the morula has developed a fluid-filled cavity called the blastocoel and differentiated into two types of cells: the inner cell mass and the trophoblast.

Question 8

Derivatives of the endoderm include ________.&#10;A) synovial membranes&#10;B) blood, bone, and lymphoid tissue&#10;C) the digestive tract&#10;D) epithelium of the respiratory tract

Accepted Answer

The answer of Derivatives of the endoderm include ________.&#10;A) synovial...

Question 9

All of the following are extraembryonic membranes EXCEPT ________.&#10;A) yolk sac&#10;B) allantois&#10;C) chorion&#10;D) placenta

Accepted Answer

The placenta is not an extraembryonic membrane, it is an organ formed from both maternal and fetal tissues. The yolk sac, allantois, and chorion are all extraembryonic membranes.

Question 10

The formation of endodermal and epidermal germ layers occurs at ________.&#10;A) gastrulation&#10;B) cleavage&#10;C) fertilization&#10;D) blastula formation

Accepted Answer

The formation of endodermal and epidermal germ layers occurs during gastrulation, which is the process of cell migration and differentiation that occurs after the blastula stage. Cleavage, fertilization, and blastula formation occur earlier in embryonic development and do not involve the formation of distinct germ layers.

Question 11

At which stage of labor is the afterbirth delivered?&#10;A) dilation stage&#10;B) expulsion stage&#10;C) placental stage&#10;D) none of the above

Accepted Answer

The answer of At which stage of labor is the...

Question 12

The trophoblast will eventually become the ________.&#10;A) allantois&#10;B) archenteron&#10;C) lining of the endometrium&#10;D) placenta

Accepted Answer

The answer of The trophoblast will eventually become the ________.&#10;A)...

Question 13

Cells on the dorsal surface of the two-layered embryonic disc migrate to form a raised groove known as the ________.&#10;A) germ cell formation&#10;B) blastocyst&#10;C) primitive streak&#10;D) amnion formation

Accepted Answer

The answer of Cells on the dorsal surface of the...

Question 14

Sperm become functional when ________.&#10;A) capacitation occurs&#10;B) they become spermatids&#10;C) stored in the uterus for several days&#10;D) the tail disappears

Accepted Answer

The answer of Sperm become functional when ________.&#10;A) capacitation occurs&#10;B)...

Question 15

Derivatives of the mesoderm include ________.&#10;A) glands of the digestive tract&#10;B) nervous tissue&#10;C) skeletal system&#10;D) none of the above

Accepted Answer

The answer of Derivatives of the mesoderm include ________.&#10;A) glands...

Question 16

Which extraembryonic membrane appears first?&#10;A) yolk sac&#10;B) amnion&#10;C) chorion&#10;D) allantois

Accepted Answer

The answer of Which extraembryonic membrane appears first?&#10;A) yolk sac&#10;B)...

Question 17

Cleavage as part as embryonic development is distinctive because it involves ________.&#10;A) cell division by mitosis&#10;B) meiosis&#10;C) the fusion of gametes&#10;D) none of the above

Accepted Answer

The answer of Cleavage as part as embryonic development is...

Question 18

The deciduas basalis is ________.&#10;A) not a maternal contribution to the placenta&#10;B) remains in the uterus after birth&#10;C) located between the developing embryo and myometrium&#10;D) none of the above

Accepted Answer

The answer of The deciduas basalis is ________.&#10;A) not a...

Question 19

The correct sequence of preembryonic structures is ________.&#10;A) zygote, morula, blastocyst&#10;B) zygote, blastocyst, morula&#10;C) morula, zygote, blastocyst&#10;D) morula, blastocyst, zygote

Accepted Answer

The answer of The correct sequence of preembryonic structures is...

Question 20

Implantation involves ________.&#10;A) placenta completion&#10;B) formation of germ layers&#10;C) fusion of egg and sperm&#10;D) embedding of the blastocyst in the uterine wall

Accepted Answer

The answer of Implantation involves ________.&#10;A) placenta completion&#10;B) formation of...

Question 21

Which trimester of pregnancy do all major organs systems begin to develop?&#10;A) first&#10;B) second&#10;C) third&#10;D) none of the above

Accepted Answer

The answer of Which trimester of pregnancy do all major...

Deck 46: Development