Question 1

Which process must sperm undergo in the female reproductive tract to increase their motility and enable successful fertilization?

Accepted Answer

Capacitation

Question 2

What is the primary mechanism that prevents polyspermy during fertilization?

Accepted Answer

Cortical reaction leading to changes in the zona pellucida

Question 3

During fertilization, what event triggers the completion of meiosis II in the oocyte?

Accepted Answer

Entry of the sperm into the oocyte cytoplasm

Question 4

Which structure forms as a result of rapid mitotic divisions of the zygote and consists of at least 16 cells?

Accepted Answer

Morula

Question 5

What is the main function of the trophoblast during early embryonic development?

Accepted Answer

Formation of the placenta and chorion

Question 6

Which hormone is secreted by the trophoblast to maintain the corpus luteum and support early pregnancy?

Accepted Answer

Human chorionic gonadotropin (hCG)

Question 7

During implantation, which layer of the trophoblast is responsible for invading and eroding the endometrium?

Accepted Answer

Syncytiotrophoblast

Question 8

Which of the following best describes the function of the placenta?

Accepted Answer

It acts as a barrier, endocrine organ, and provides nutritive, respiratory, and excretory functions.

Question 9

If implantation does not occur, what happens to the endometrium?

Accepted Answer

It becomes nonreceptive and is shed during menstruation.

Question 10

Which equation best represents the chromosomal combination after fertilization?

Accepted Answer

$$n + n = 2n$$

Question 11

Which structure connects the embryo to the placenta, allowing exchange of nutrients and waste?

Accepted Answer

Umbilical cord

Question 12

What is the primary role of chorionic villi in placental development?

Accepted Answer

They increase surface area for exchange between maternal and fetal blood.

Question 13

Which of the following is TRUE regarding maternal and fetal blood in the placenta?

Accepted Answer

Maternal and fetal blood are separated by thin capillary endothelium.

Question 14

Which event marks the transition from embryo to fetus?

Accepted Answer

Beginning of week 9 after fertilization

Question 15

Which of the following is a consequence of the Ca$$^{2+}$$ surge during fertilization?

Accepted Answer

Completion of meiosis II in the oocyte

Question 16

Which layer of the endometrium is involved in forming the maternal portion of the placenta?

Accepted Answer

Decidua basalis

Question 17

Which hormone peaks by the end of the second month of pregnancy and then declines as the placenta takes over hormone production?

Accepted Answer

Human chorionic gonadotropin (hCG)

Question 18

Which of the following best describes cleavage during early embryonic development?

Accepted Answer

Rapid mitotic divisions resulting in blastomeres

Question 19

Which structure is formed by the inner cell mass of the blastocyst?

Accepted Answer

Embryo and extraembryonic membranes

Question 20

Which of the following is a plausible reason for early miscarriage after implantation?

Accepted Answer

Genetic abnormalities or unknown causes

Pregnancy and Human Development: Fertilization to Placentation

Study Guide - Practice Questions