Question 1

Which structure in the sperm cell contains enzymes necessary for penetrating the oocyte's zona pellucida during fertilization?

Accepted Answer

Acrosome

Question 2

What is the primary function of the mitochondria located in the middle piece of the sperm?

Accepted Answer

To provide energy for motility

Question 3

Which event marks the completion of fertilization?

Accepted Answer

The maternal and paternal chromosomes combine to form a diploid zygote

Question 4

What is the fast block to polyspermy, and how is it achieved?

Accepted Answer

Depolarization of the oocyte membrane; by influx of sodium ions

Question 5

During which stage of development does the conceptus implant into the uterine wall?

Accepted Answer

Blastocyst

Question 6

Which hormone is responsible for maintaining the corpus luteum during early pregnancy?

Accepted Answer

Human chorionic gonadotropin (HCG)

Question 7

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

Accepted Answer

To protect the embryo against physical trauma and maintain temperature

Question 8

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

Accepted Answer

Ectoderm

Question 9

A newborn has difficulty breathing due to a lack of surfactant. This condition is most likely due to which of the following?

Accepted Answer

Premature birth before the last months of gestation

Question 10

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

Accepted Answer

It is a temporary organ that functions in nutrition, respiration, excretion, and hormone production

Question 11

Which structure allows oxygenated blood from the placenta to bypass the fetal liver and enter the inferior vena cava?

Accepted Answer

Ductus venosus

Question 12

What is the fate of the foramen ovale after birth?

Accepted Answer

It fuses to form the fossa ovalis

Question 13

Which of the following is a teratogen that can cause fetal alcohol syndrome (FAS)?

Accepted Answer

Alcohol

Question 14

During gastrulation, which structure establishes the longitudinal axis of the embryo?

Accepted Answer

Primitive streak

Question 15

Which of the following best explains why only one sperm normally fertilizes an oocyte in humans?

Accepted Answer

Fast and slow blocks to polyspermy prevent entry of additional sperm

Question 16

Which event occurs immediately after the sperm nucleus enters the oocyte cytoplasm?

Accepted Answer

The oocyte completes meiosis II

Question 17

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

Accepted Answer

They are separated by the chorionic villi and capillary endothelium

Question 18

Which of the following is a correct sequence of early embryonic development?

Accepted Answer

Zygote → Morula → Blastocyst → Gastrula

Question 19

Which fetal structure allows blood to bypass the nonfunctional fetal lungs by connecting the pulmonary trunk to the aorta?

Accepted Answer

Ductus arteriosus

Question 20

A patient is found to have a single umbilical artery instead of the normal two. Which of the following is a possible consequence?

Accepted Answer

Reduced oxygen and nutrient delivery to the fetus

Human Development: From Fertilization to Birth

Study Guide - Practice Questions