Question 1

During the pre-embryonic period, which process is responsible for transforming the zygote into a solid ball of 16-32 cells known as the morula?

Accepted Answer

Cleavage divisions

Question 2

Which structure is formed when the blastocyst attaches to the endometrium of the uterine wall?

Accepted Answer

Implantation

Question 3

The trophoblast cells of the blastocyst differentiate to form which structure that provides nutrients to the developing embryo?

Accepted Answer

Chorion

Question 4

Which of the following is NOT a function of the amnion during embryonic development?

Accepted Answer

Provides nutrients to the embryo

Question 5

If a mutation prevented the formation of the hypoblast, which extra-embryonic membrane would be most directly affected?

Accepted Answer

Yolk sac

Question 6

Which layer is responsible for forming the three germ layers during the embryonic period?

Accepted Answer

Epiblast

Question 7

A patient presents with abnormal development of the fetal blood supply. Which extra-embryonic membrane is most likely involved?

Accepted Answer

Chorion

Question 8

Which of the following correctly matches the extra-embryonic membrane with its primary function?

Accepted Answer

Chorion – surrounds all embryonic membranes

Question 9

During which period do the major organ systems become almost completely formed and the heart begins to beat?

Accepted Answer

Embryonic period

Question 10

Which of the following is derived from the hypoblast and is involved in the formation of the digestive tract?

Accepted Answer

Yolk sac

Question 11

If the blastocyst fails to implant in the uterine wall, which of the following outcomes is most likely?

Accepted Answer

Pregnancy will not be established

Question 12

Which extra-embryonic membrane is responsible for the exchange of nutrients, wastes, oxygen, and carbon dioxide between fetal and maternal blood?

Accepted Answer

Chorion

Question 13

The allantois is primarily involved in which function during embryonic development?

Accepted Answer

Formation of the umbilical cord and urinary bladder

Question 14

Which of the following best describes the role of the epiblast during early embryonic development?

Accepted Answer

Differentiates into the three germ layers

Question 15

A researcher is studying the formation of the bilaminar embryonic disc. Which two cell layers are involved?

Accepted Answer

Epiblast and hypoblast

Question 16

Which of the following equations best represents the number of cells in a morula after $n$ cleavage divisions, starting from a single zygote?

Accepted Answer

$2^n$

Question 17

If the embryonic disc fails to form the three germ layers, which developmental process is most directly affected?

Accepted Answer

Organogenesis

Question 18

Which extra-embryonic membrane is most important for temperature regulation and shock absorption for the developing embryo?

Accepted Answer

Amnion

Question 19

During the fetal period, which of the following best describes the primary developmental process?

Accepted Answer

Growth and maturation of organs

Question 20

A medical case describes a fetus with abnormal urinary bladder development. Which extra-embryonic membrane is most likely implicated?

Accepted Answer

Allantois

Human Embryonic and Fetal Development: Key Stages and Structures

Study Guide - Practice Questions