Question 1

Which of the following best describes the process of capacitation in sperm?

Accepted Answer

It is the process by which sperm membranes become fragile and permeable to Ca$$^{2+}$$, enabling the acrosome reaction.

Question 2

During fertilization, what prevents polyspermy (fertilization by more than one sperm)?

Accepted Answer

Fast and slow blocks: Na$$^+$$ channels depolarize the egg membrane and cortical granules release enzymes to harden the zona pellucida.

Question 3

Which of the following is the correct sequence of early embryonic development after fertilization?

Accepted Answer

Zygote → Cleavage → Morula → Blastocyst

Question 4

A blastocyst typically implants into the uterine wall how many days after ovulation?

Accepted Answer

About 6 days

Question 5

Which embryonic germ layer gives rise to the nervous system and epidermis?

Accepted Answer

Ectoderm

Question 6

What is the primary function of the amnion during embryonic development?

Accepted Answer

To protect the embryo from trauma, infection, and temperature fluctuations

Question 7

Which of the following best explains why the placenta is considered a selective barrier?

Accepted Answer

It allows nutrients and oxygen to pass to the fetus, while fetal wastes pass to the mother for elimination.

Question 8

Which of the following is a consequence of fetal alcohol syndrome (FAS)?

Accepted Answer

Malformed facial features and central nervous system defects

Question 9

Which structure allows most fetal blood to bypass the lungs by connecting the pulmonary artery to the aorta?

Accepted Answer

Ductus arteriosus

Question 10

Which of the following best describes monozygotic twins?

Accepted Answer

They result from one fertilized egg that splits, and are genetically identical.

Question 11

A patient presents with an ectopic pregnancy. Where is the most common site for implantation in this condition?

Accepted Answer

Uterine tube (fallopian tube)

Question 12

Which hormone is secreted by the trophoblast and is detected by pregnancy tests?

Accepted Answer

Human chorionic gonadotropin (hCG)

Question 13

Which of the following events occurs during the process of cleavage?

Accepted Answer

The zygote undergoes mitotic divisions without increasing in size.

Question 14

Which of the following is a function of the yolk sac in early embryonic development?

Accepted Answer

It provides the initial site of blood cell formation.

Question 15

Which of the following best describes the role of the syncytiotrophoblast during implantation?

Accepted Answer

It digests endometrial cells, allowing the embryo to embed in the uterine wall.

Question 16

Which of the following is true regarding the formation of the three primary germ layers during gastrulation?

Accepted Answer

The mesoderm forms muscle, bone, and blood.

Question 17

A newborn is diagnosed with a congenital heart defect that allows blood to flow from the right atrium directly into the left atrium. Which fetal structure failed to close after birth?

Accepted Answer

Foramen ovale

Question 18

Which of the following is a likely outcome if the cortical reaction fails to occur during fertilization?

Accepted Answer

Polyspermy may occur, resulting in a nonviable zygote.

Question 19

Which of the following best explains why the placenta is considered an incomplete barrier?

Accepted Answer

It allows some harmful substances, such as alcohol and certain viruses, to cross from mother to fetus.

Question 20

Which of the following is a critical function of the chorion during pregnancy?

Accepted Answer

It contributes to the formation of the placenta and secretes hormones.

Chapter 28 Pregnancy and Human Development Notes

Study Guide - Practice Questions

Study Guide - Flashcards