AP Biology : Understanding Other Reproductive Physiology

Study concepts, example questions & explanations for AP Biology

varsity tutors app store varsity tutors android store

Example Questions

Example Question #81 : Reproductive Physiology

Which of the following best describes the role of the bulbourethral gland?

Possible Answers:

It contributes proteolytic enzymes to semen 

It contracts to initiate ejaculation 

It contributes fructose to semen 

It lubricates the urethra

Correct answer:

It lubricates the urethra

Explanation:

The bulbourethral gland is a part of the male reproductive system that contributes protein-rich fluid to semen and lubricates the urethra.

Example Question #81 : Reproductive Physiology

Which of the following best describes the place where all secretions that form the ejaculate combine?

Possible Answers:

Urethra

Ejaculatory duct

Epididymis

Glans penis 

Correct answer:

Ejaculatory duct

Explanation:

Prior to ejaculation, secretions from the bulbourethral gland, prostate gland, epididymis, and seminal vesicles enter the ejaculatory duct. The ejaculatory duct is the place where semen mixes and is stored until ejaculation.

Example Question #1592 : Ap Biology

Which of the following best explains why ejaculation has a high fructose concentration?

Possible Answers:

To lubricate the urethra 

To increase alkalinity 

To provide energy for the sperm cells 

To degrade the zona pellucida 

Correct answer:

To provide energy for the sperm cells 

Explanation:

Seminal vesicles secrete a large portion of the components that make up semen. A high concentration of fructose is included in these secretions. The fructose provides energy rich molecules for sperm cell movement.

Example Question #11 : Understanding Other Reproductive Physiology

Which of the following parts of the male reproductive system carries the semen out of the penis?

Possible Answers:

Urethra

Epididymis

Seminiferous tubules

Vas deferens

Correct answer:

Urethra

Explanation:

In males, the urethra carries semen from the ejaculatory duct out of the penis. The urethra also carries urine from the bladder through the penis.

Example Question #11 : Understanding Other Reproductive Physiology

During copulation, where does the penis release the ejaculate in the female reproductive tract?

Possible Answers:

Cervix

Vagina

Uterus

Fallopian tubes

Correct answer:

Vagina

Explanation:

During copulation and sexual intercourse, the penis enters the female vagina. Ejaculation—the release of semen from the penis—also occurs in the vagina.

Example Question #12 : Understanding Other Reproductive Physiology

Which of the following choices best describes the impact of an influx of intracellular calcium on sperm cells during capacitation?

Possible Answers:

It destabilizes the sperm's plasma membrane

It aids in chemotaxis towards the oocyte

It increases sperm cell motility 

It triggers the acrosomal reaction 

Correct answer:

It increases sperm cell motility 

Explanation:

During capacitation, sperm cells undergo biochemical changes that allow for fertilization of the oocyte. One of these changes is an influx of intracellular calcium, which leads to an increase in intracellular cAMP levels. The high levels of calcium and cAMP promote hyperactivation—increased motility—through deeper tail bends. This change in sperm tail movement is accompanied by the adoption of a swinging movement by the head of the cell. These changes in motility patterns help sperm cell movement within the female reproductive tract.

Example Question #321 : Systems Physiology

The acrosomal reaction is triggered when sperm cells bind to which of the following cell layers?

Possible Answers:

The lipids within the semen

The oocyte plasma membrane

The epithelial cells on the vaginal wall

The glycoproteins within the zona pellucida

Correct answer:

The glycoproteins within the zona pellucida

Explanation:

Sperm cells bind to ZP3 glycoproteins in the zona pellucida—a layer surrounding the oocyte that is composed of glycoproteins. This binding triggers the acrosomal reaction in the sperm cell. Once inside the female reproductive tract, sperm cells undergo capacitation. The subsequent state of hyperactivity allows sperm cells to successfully move up the fallopian tubes towards the oocyte. Once a sperm cell encounters the cell layers surrounding the oocyte, the sperm binds and penetrates the layers of cells surrounding the oocyte until it reaches the zona pellucida.

Example Question #12 : Understanding Other Reproductive Physiology

Which of the following best describes what happens to the acrosome during the acrosomal reaction?

Possible Answers:

It fuses with lysosomes for degradation

Its contents are ingested by the oocyte via phagocytosis

It fuses with the plasma membrane for release

It is digested by the sperm cell

Correct answer:

It fuses with the plasma membrane for release

Explanation:

The acrosomal reaction in sperm cells is another process that aids in fusing the sperm and oocyte. After binding to glycoproteins in the zona pellucida, the acrosome—cap of the sperm cell—fuses with the sperm plasma membrane. This fusion causes the release of acrosomal contents, which include enzymes that allow the sperm cell to move further towards the oocyte.

Example Question #13 : Understanding Other Reproductive Physiology

Which of the following can be best described as the final step of the acrosomal reaction in mammals?

Possible Answers:

Pronuclei fusion

Sperm cell and oocyte plasma membrane fusion

Penetration of the acrosome into the oocyte

Release of the acrosomal contents

Correct answer:

Sperm cell and oocyte plasma membrane fusion

Explanation:

During the acrosomal reaction, the sperm cell acrosome fuses with the plasma membrane, releasing digestive enzymes. These digestive enzymes—acrosin and hyaluronidase—break down the layers surrounding the oocyte as well as parts of the oocyte plasma membrane itself. The plasma membranes of the sperm cell and oocyte then fuse, which completes the acrosomal reaction.

Example Question #11 : Understanding Other Reproductive Physiology

Which of the following best describes how genetic materials combine after the sperm and oocyte fuse?

Possible Answers:

Pronuclei fusion

A mitotic spindle links the pronuclei nuclear membranes 

Chromosomes combine after nuclear membrane dissolution

Chromosomes freely diffuse in the oocyte cytoplasm

Correct answer:

Chromosomes combine after nuclear membrane dissolution

Explanation:

After the sperm cell and oocyte fuse, the sperm’s pronucleus enters the oocyte. The oocyte completes meiosis II while the sperm’s tail and mitochondria degrade. The pronuclei migrate towards one another within the oocyte and replicate genetic material in preparation for genome fusion and mitosis. The nuclear membranes of the sperm and egg pronuclei dissolve; however, a mitotic spindle tethers the chromosomes together and prevents the genetic material from diffusing. The genetic material then undergoes mitosis, which fuses the maternal and paternal chromosomes into one diploid genome.

Learning Tools by Varsity Tutors