Human Reproduction and Menstrual Cycle Review Flashcards

Flashcards covering human reproductive systems (male and female anatomy, gametogenesis, sperm structure) and the hormonal regulation of the menstrual cycle.

Where is Follicle Stimulating Hormone (FSH) produced, and what is its target organ?

FSH is produced in the pituitary gland and targets the ovaries.

Where is Luteinizing Hormone (LH) produced, and what is its target organ?

LH is produced in the pituitary gland and targets the ovaries.

Where is Oestrogen produced, and what is its target organ in the menstrual cycle?

Oestrogen is produced in follicle cells (and corpus luteum) and targets the pituitary gland.

Where is Progesterone produced, and what is its target organ in the menstrual cycle?

Progesterone is produced in the corpus luteum and targets the pituitary gland.

Which diagram summarizes the four hormones of the menstrual cycle along with their production sites and target organs?

This diagram shows that FSH and LH are produced in the pituitary gland and target the ovaries, while Oestrogen and Progesterone are produced in the ovaries and target the pituitary gland.

What are the main functions of FSH in the menstrual cycle?

FSH causes follicle maturation and stimulates the secretion of Oestrogen.

What are the main functions of Oestrogen in the menstrual cycle?

Oestrogen stimulates uterus lining repair, inhibits FSH release, and stimulates LH release.

What are the main functions of Luteinizing Hormone (LH) in the menstrual cycle?

LH induces ovulation, stimulates Progesterone production, and inhibits Oestrogen production in the corpus luteum.

What are the main functions of Progesterone in the menstrual cycle?

Progesterone prepares and maintains the uterus lining while inhibiting the release of LH and FSH.

In the FOLP model of the menstrual cycle, what is meant by positive action and negative feedback?

Positive action means one hormone induces the production of another hormone, whereas negative feedback means one hormone inhibits the production of another hormone.

What events occur during Days 1–5 of the menstrual cycle?

The uterus lining sheds during menstruation, and FSH released from the pituitary gland induces Oestrogen in the developing follicle.

What events occur during Days 6–13 (Follicular phase) of the menstrual cycle?

Oestrogen inhibits FSH so only one egg matures, induces repair of the uterus lining, and induces LH release. LH then induces thickening of the uterus lining.

What major event takes place on Day 14 of the menstrual cycle?

LH peaks, causing the follicle to release an egg (ovulation) and transform into the corpus luteum (yellow body).

What events occur during Days 15–24 (Luteal phase) of the menstrual cycle?

The corpus luteum produces Progesterone, which maintains the uterus lining and inhibits FSH and LH in the pituitary gland.

What occurs during Days 25–28 of the menstrual cycle if the egg is not fertilized?

The corpus luteum degenerates, Progesterone decreases, the uterus lining is no longer maintained, menstruation occurs, and FSH rises again to begin a new cycle.

What are the two primary functions of the testis?

The testis produces sperms and testosterone.

What is the function of the epididymis?

The epididymis temporarily stores inactive sperms before ejaculation.

What glands produce semen and what is its composition?

The seminal vesicle, prostate gland, and Cowper's gland produce semen, which is a mixture of fluid containing nutrients and enzymes that nourish and activate sperms.

Why is the scrotum positioned outside the main body cavity?

Sperm development requires a temperature lower than normal body temperature.

Which diagram displays the structure and function of the male reproductive system?

This diagram highlights male reproductive organs including the testis, epididymis, vas deferens, urethra, seminal vesicle, prostate gland, Cowper's gland, scrotum, and penis along with their functions.

What is the function of the Fallopian tube (oviduct)?

It is a narrow, muscular tube leading from the ovary to the uterus where egg fertilization takes place.

What is the function of the uterus (womb)?

The uterus is where the baby develops during pregnancy; it has muscular walls and an inner lining (endometrium), part of which is sloughed off monthly during menstruation.

What is the function of the cervix?

The cervix is a circular ring of muscle that enlarges to allow passage of the fetus during birth.

How many potential cells are present at birth in a female ovary, and how many mature into ova over her lifetime?

About $70{,}000$ potential cells are present at birth, but only about $500$ mature ova are released from puberty to menopause.

Which diagram illustrates ovary anatomy and follicle development?

This diagram shows primary follicles, secondary follicles, vesicular (Graafian) follicle, secondary oocyte release, and the corpus luteum inside the ovary.

What is the definition of a gamete?

A reproductive cell containing the haploid number of chromosomes ($n$).

What are the cellular stages in sperm production (spermatogenesis)?

A diploid spermatogonium ($2n$, $46$ chromosomes) forms a primary spermatocyte, undergoes Meiosis I to form secondary spermatocytes, undergoes Meiosis II to form spermatids, and differentiates into haploid sperm ($n$, $23$ chromosomes).

Which diagram outlines the process of sperm production from diploid spermatogonium to haploid sperms?

This diagram displays the meiotic divisions (Meiosis I and Meiosis II) and differentiation from a spermatogonium ($2n$) through primary/secondary spermatocytes and spermatids to mature sperms ($n$).

What is the function of the acrosome in a sperm cell?

The acrosome is a sac containing enzymes that break down the egg membrane so the sperm can penetrate during fertilization.

What is the function of the mitochondria located in the sperm's midpiece?

The mitochondria provide energy for sperm activity.

What is the function of the sperm flagellum (tail)?

The flagellum enables the sperm to swim towards the egg.

What product is formed when sperm and egg fuse, and by what process does it develop into an embryo?

A haploid sperm ($n$) and a haploid egg ($n$) fuse during fertilization to form a diploid zygote ($2n$), which undergoes mitosis to form an embryo.