Reproductive Physiology Practice Questions

Q: Which of the following hormones play an important role in pubertal development?

All of the options play a role in puberty.. ***All of the options play a role in puberty.*** - Puberty is a complex process involving the interplay of various hormones, including **gonadotropins (LH)**, **sex steroids (testosterone)**, and metabolic hormones like **leptin**. - All these hormones contribute directly or indirectly to the **initiation and progression of pubertal development**. *Luteinizing Hormone (LH)* - While essential for **gonadal steroid production** and a key marker of puberty, LH alone does not *initiate* the process; it is part of a larger hormonal cascade. - LH levels rise significantly *during* puberty to stimulate the gonads, but its release is ultimately triggered by **GnRH**. *Testosterone* - **Testosterone** is crucial for the development of **secondary sexual characteristics** in males and contributes to growth in both sexes during puberty. - However, its production is stimulated by LH, meaning it acts downstream in the pubertal cascade and is not the sole initiator. *Leptin* - **Leptin**, a hormone produced by **adipose tissue**, is thought to play a permissive role in the timing of puberty. - High enough **body fat stores** and therefore adequate leptin levels are believed to signal to the brain that the body has sufficient energy reserves for reproductive development, but it's not the direct hormonal trigger.

Q: Which of the following changes is NOT seen during the capacitation of sperm?

Decreased permeability to calcium. ***Decreased permeability to calcium*** - **Capacitation** involves an **influx of calcium ions** into the sperm, which is crucial for subsequent acrosome reaction and hyperactivated motility. - Therefore, a *decrease* in calcium permeability would hinder, not facilitate, the necessary changes for fertilization. *Increased permeability to calcium ions* - This is a **characteristic event** during capacitation, as **calcium influx** triggers downstream signaling pathways. - The increased intracellular calcium is essential for the sperm to undergo the **acrosome reaction** and develop **hyperactivated motility**. *Removal of cholesterol from the sperm membrane* - **Cholesterol efflux** from the sperm plasma membrane is a key event in capacitation, making the membrane more fluid. - This increased fluidity is necessary for the **acrosome reaction** to occur, allowing the outer acrosomal membrane to fuse with the plasma membrane. *Increased motility* - During capacitation, sperm develop **hyperactivated motility**, characterized by a more vigorous and asymmetric flagellar beat. - This change in motility is essential for the sperm to navigate through the female reproductive tract and penetrate the egg's outer layers.

Q: Within what timeframe after ovulation does fertilization typically occur?

12-24 hours. ***12-24 hours*** - The **ovum** is viable for fertilization for a relatively short period, typically **12 to 24 hours** after its release during ovulation. - For fertilization to occur, **sperm** must be present in the fallopian tube within this critical window. *5-6 days* - This timeframe is more characteristic of the **duration that sperm can survive** in the female reproductive tract, rather than the viability of the ovum for fertilization. - If sperm are present in the reproductive tract up to **5-6 days before ovulation**, they may still fertilize the egg once it's released. *8-12 days* - This period extends significantly beyond the **viability of the ovum** for fertilization. - An ovum released during ovulation will have degenerated and will no longer be capable of being fertilized after 24 hours. *> 12 days* - Fertilization cannot occur this late after ovulation as the **egg would have long since degenerated**. - This timeframe is not relevant to the process of fertilization itself.

Q: What is the role of growth hormone in the early stages of spermatogenesis?

Stimulates early division of spermatogonia. ***Stimulates early division of spermatogonia*** - **Growth hormone** plays a crucial permissive role in the initial stages of spermatogenesis, primarily by promoting the early **mitotic divisions of spermatogonia**. - This hormone ensures an adequate pool of spermatogonial stem cells to proceed through the later stages of sperm development. *Promotes late division of spermatocytes* - The progression from **primary spermatocytes** to **secondary spermatocytes** involves meiosis I, which is primarily regulated by **FSH** and **testosterone**, not directly by growth hormone. - Growth hormone's main impact is earlier in the proliferation phase of spermatogonia, rather than the meiotic divisions of spermatocytes. *Stimulates Sertoli and Leydig cells* - **Sertoli cells** are primarily stimulated by **FSH**, and **Leydig cells** are stimulated by **LH**, leading to **testosterone production**. - While growth hormone may indirectly influence the overall testicular environment, its direct and primary role is not the stimulation of these specific cell types. *Facilitates formation of acrosomes* - **Acrosome formation** occurs during **spermiogenesis**, the final stage of spermatid maturation. - This process is mainly dependent on **testosterone** and the intricate cellular machinery within the spermatid, with no direct or primary role specifically attributed to growth hormone.

Q: After how many days post-ovulation does the corpus luteum begin to regress?

10 days. ***10 days*** - The corpus luteum begins to regress approximately **9-11 days post-ovulation** in the absence of pregnancy, making **10 days** the correct answer. - This regression, known as **luteolysis**, is triggered by declining levels of **LH** and leads to decreased production of **progesterone** and **estrogen**. - The functional regression marks the end of the luteal phase and precedes menstruation by approximately 3-4 days. *5 days* - At 5 days post-ovulation, the corpus luteum is in its **active growth phase** and approaching peak function. - **Progesterone** levels are rising to maintain the endometrium, not declining. - Regression has not yet begun at this early stage of the luteal phase. *24 days* - This timing is too late - at 24 days post-ovulation (approximately day 38 of the cycle), menstruation would have already occurred. - In a typical **28-day cycle**, menstruation begins around day 14 post-ovulation. - Such delayed regression would only occur with **pregnancy** and hCG support, preventing luteolysis. *None of the options* - This is incorrect because **10 days** is the medically accurate answer, falling within the established 9-11 day timeframe for corpus luteum regression.

Q: Which of the following is an estrogen-dependent pubertal change?

Vaginal Cornification. ***Vaginal Cornification*** - Vaginal cornification refers to the **maturation and stratification of the vaginal epithelium** under the direct influence of **estrogen**. - Estrogen stimulates the **proliferation of vaginal epithelial cells**, leading to thickening of the vaginal mucosa and increased glycogen content in the superficial cells. - This is a **purely estrogen-dependent change** and is one of the key markers of estrogenic activity during puberty. - The vaginal maturation index increases with estrogen exposure, making this a reliable indicator of estrogenic stimulation. *Menstruation* - While estrogen is important for endometrial proliferation, menstruation requires the **coordinated action of both estrogen AND progesterone**. - Estrogen builds the endometrium during the proliferative phase, but **progesterone** is essential for the secretory transformation. - Menstruation occurs due to the **withdrawal of both hormones**, not estrogen alone, making it dependent on both hormones rather than purely estrogen-dependent. *Cervical mucus* - Cervical mucus characteristics are influenced by **both estrogen and progesterone** throughout the menstrual cycle. - Estrogen makes mucus thin, watery, and stretchy (spinnbarkeit), while progesterone makes it thick and viscous. - This **dual hormonal regulation** means it is not purely estrogen-dependent. *Hair growth* - Pubertal hair growth, including **pubic and axillary hair**, is primarily stimulated by **androgens** (testosterone, DHEA-S from the adrenal glands). - This process is called **adrenarche** and is androgen-dependent, not estrogen-dependent.

Q: Day 20 of menstrual cycle falls under which phase?

Luteal phase. ***Luteal phase*** - The **luteal phase** typically starts after ovulation, around day 14, and lasts until menstruation begins, usually day 28 of a 28-day cycle. Therefore, **day 20 falls squarely within this phase**. - During this phase, the **corpus luteum** forms and produces **progesterone**, preparing the uterus for potential pregnancy. *Menstrual phase* - The **menstrual phase** is the period of shedding of the uterine lining, typically occurring from **day 1 to day 5** of the menstrual cycle. - Day 20 is well past this phase, during which bleeding and low hormone levels are characteristic. *Follicular phase* - The **follicular phase** starts on day 1 of menstruation and lasts until ovulation, usually around **day 13-14** in a 28-day cycle. - During this phase, follicles mature under the influence of **FSH** and **estrogen** levels rise. Day 20 is beyond this period. *Ovulation phase* - The **ovulation phase** is a short period, typically around **day 14** of a 28-day cycle, when the mature egg is released from the ovary. - This phase is brief and marks the transition from the follicular to the luteal phase, so day 20 is considerably after ovulation.

Q: Which hormone is predominantly secreted after 14 days of the menstrual cycle?

Progesterone. ***Correct: Progesterone*** - After **ovulation**, which typically occurs around day 14 of a 28-day cycle, the ruptured follicle transforms into the **corpus luteum**. - The **corpus luteum** primarily secretes **progesterone**, which is crucial for preparing the **endometrium** for potential implantation. - Progesterone is the **predominant hormone** of the **luteal phase** (days 14-28). *Incorrect: Estrogen* - **Estrogen** levels rise significantly during the **follicular phase** (days 1-14), peaking just before ovulation. - After ovulation, **estrogen** levels decrease slightly and then rise again during the **luteal phase**, but its predominant role is earlier in the cycle. *Incorrect: LH (Luteinizing Hormone)* - **LH** experiences a surge around day 14, known as the **LH surge**, which triggers **ovulation**. - After this surge, LH levels decline and remain relatively low throughout the rest of the **menstrual cycle**, though it's essential for maintaining the **corpus luteum**. *Incorrect: FSH (Follicle-Stimulating Hormone)* - **FSH** is highest during the early **follicular phase**, stimulating the growth and development of ovarian follicles. - Its levels decrease as **estrogen** rises and remain low after ovulation, as its primary role is follicle maturation, not luteal phase events.

Q: Antimullerian hormone is secreted by ?

Both Sertoli cells and granulosa cells. ***Both Sertoli cells and granulosa cells*** - **Antimullerian hormone (AMH)** is produced by **Sertoli cells in males** and **granulosa cells in females** - In **males**: Sertoli cells secrete AMH during fetal development to cause **regression of Müllerian ducts** (which would otherwise develop into uterus, fallopian tubes, and upper vagina) - In **females**: Granulosa cells of developing ovarian follicles secrete AMH, which serves as a **marker of ovarian reserve** and inhibits excessive follicle recruitment - This is the only option that correctly identifies both cell types that produce AMH *Theca cells* - Theca cells are found in ovarian follicles and produce **androgens** (androstenedione and testosterone), not AMH - These androgens are converted to estrogens by granulosa cells via aromatase enzyme - Theca cells do not produce antimullerian hormone *Leydig cells* - Leydig cells are located in the **testes** and produce **testosterone** - They do not produce antimullerian hormone - Only Sertoli cells (not Leydig cells) produce AMH in males *None of the above* - This is incorrect because AMH is indeed produced by specific cell types: **Sertoli cells in males** and **granulosa cells in females**

Q: The role of human placental lactogen is :

Supports fetal growth and development.. ***Supports fetal growth and development.*** - Human placental lactogen (hPL) acts as a **growth hormone** for the fetus, primarily by altering maternal metabolism to favor fetal nutrient supply. - It increases **maternal insulin resistance**, leading to higher maternal glucose and free fatty acids, which are then shunted to the fetus, supporting its growth and development. *Stimulate milk production* - **Prolactin**, secreted by the anterior pituitary, is the primary hormone responsible for stimulating milk production (lactogenesis). - While hPL has some structural similarity to growth hormone and prolactin, its primary role is not to directly stimulate milk production during pregnancy; rather, it prepares the breasts. *Promotes growth of breast for lactation.* - hPL, along with **estrogen** and **progesterone**, contributes to the **mammary gland development** during pregnancy, preparing the breasts for lactation. - However, its direct role is more about **mammary gland proliferation and differentiation** rather than initiation of milk production. *Provide fetal nutrition by antagonizing the action of insulin in maternal circulation, breakdown of fats and proteins and transport of fatty acids and amino acids from maternal to fetal circulation.* - This is a highly detailed and largely accurate description of *how* hPL supports fetal growth and development, making it a mechanism rather than the primary, concise role. - It describes the metabolic changes induced by hPL, which ultimately lead to the **support of fetal growth and development**.

Question 1

Which of the following hormones play an important role in pubertal development?

Accepted Answer

All of the options play a role in puberty.

Answer

Luteinizing Hormone (LH)

Answer

Testosterone

Answer

Leptin

Question 2

Which of the following changes is NOT seen during the capacitation of sperm?

Accepted Answer

Decreased permeability to calcium

Answer

Removal of cholesterol from the sperm membrane

Answer

Increased permeability to calcium ions

Answer

Increased motility

Question 3

Within what timeframe after ovulation does fertilization typically occur?

Accepted Answer

12-24 hours

Answer

5-6 days

Answer

8-12 days

Answer

> 12 days

Question 4

What is the role of growth hormone in the early stages of spermatogenesis?

Accepted Answer

Stimulates early division of spermatogonia

Answer

Promotes late division of spermatocytes

Answer

Stimulates Sertoli and Leydig cells

Answer

Facilitates formation of acrosomes

Question 5

After how many days post-ovulation does the corpus luteum begin to regress?

Accepted Answer

10 days

Answer

None of the options

Answer

5 days

Answer

24 days

Question 6

Which of the following is an estrogen-dependent pubertal change?

Accepted Answer

Vaginal Cornification

Answer

Cervical mucus

Answer

Menstruation

Answer

Hair growth

Question 7

Day 20 of menstrual cycle falls under which phase?

Accepted Answer

Luteal phase

Answer

Menstrual phase

Answer

Follicular phase

Answer

Ovulation phase

Question 8

Which hormone is predominantly secreted after 14 days of the menstrual cycle?

Accepted Answer

Progesterone

Answer

Estrogen

Answer

LH

Answer

FSH

Question 9

Antimullerian hormone is secreted by ?

Accepted Answer

Both Sertoli cells and granulosa cells

Answer

Theca cells

Answer

Leydig cells

Answer

None of the above

Question 10

The role of human placental lactogen is :

Accepted Answer

Supports fetal growth and development.

Answer

Stimulate milk production

Answer

Promotes growth of breast for lactation.

Answer

Provide fetal nutrition by antagonizing the action of insulin in maternal circulation, breakdown of fats and proteins and transport of fatty acids and amino acids from maternal to fetal circulation.

Reproductive Physiology — MCQs

Reproductive Physiology — MCQs

On this page

Practice by Chapter

Want unlimited practice?