Female repro A/P

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Questions and Answers

What is the primary location of oocyte development within the ovaries?

Fallopian Tubes

Ovarian Stroma

Ovarian Medulla

Ovarian Cortex (correct)

What is expelled during ovulation?

Oogonium

Polar body

Secondary oocyte (correct)

Primary oocyte

Which phase of the ovarian cycle involves the development of oocytes?

Luteal Phase

Menstrual Phase

Follicular Phase (correct)

Ovulation Phase

How many primordial germ cells does an embryonic ovary contain?

Around 3 million Signup and view all the answers

What are the two main phases of the ovarian cycle called?

Follicular and Luteal Phase Signup and view all the answers

What is the main function of the endometrium in the uterus?

To line the uterus and produce secretions Signup and view all the answers

Which layer of the uterus is primarily composed of smooth muscle?

Myometrium Signup and view all the answers

Where is the internal os located within the cervix?

At the opening from the cavity of the body to the cervix Signup and view all the answers

What anatomical feature is described as the portion above the entrance of the uterine tubes?

Fundus Signup and view all the answers

Which part of the vagina is deeper and covered with peritoneum?

Posterior fornix Signup and view all the answers

What is the description of the normal position of the uterus?

Anteverted Signup and view all the answers

What is the main role of ovarian hormones in the female reproductive system?

To stimulate the development of follicles Signup and view all the answers

During which phase of the menstrual cycle are corkscrew-shaped glands primarily present in the endometrium?

Secretory phase Signup and view all the answers

What anatomical structure forms the posterior part of the uterine cavity and is the lowest part of the peritoneal cavity?

Pouch of Douglas Signup and view all the answers

What is the primary composition of the perimetrium?

Serous membrane Signup and view all the answers

What happens during ovulation?

Rupture of the Graafian follicle and release of a secondary oocyte Signup and view all the answers

Which hormone surge triggers ovulation?

Luteinizing Hormone (LH) Signup and view all the answers

What is the role of Follicle Stimulating Hormone (FSH) in the ovarian cycle?

It initiates the growth of primary ovarian follicles Signup and view all the answers

What forms from the remaining follicle after ovulation?

Corpus luteum Signup and view all the answers

Which cycle typically lasts about 28 days and includes multiple hormonal changes?

Ovarian cycle Signup and view all the answers

What effect does Luteinizing Hormone (LH) have on dominant follicles?

Enhances LH receptor acquisition in dominant follicles Signup and view all the answers

What happens to the follicles maturing in each cycle?

Only one will fully mature into a secondary follicle Signup and view all the answers

What role does Luteinizing Hormone (LH) play in the ovarian cycle?

It induces ovulation. Signup and view all the answers

Which hormone is responsible for preventing the development of surrounding primary follicles?

Anti Mullerian Hormone Signup and view all the answers

What happens during the menstrual cycle if fertilization does not occur?

The stratum functionalis is shed. Signup and view all the answers

During which stage of the menstrual cycle does the proliferation and repair of the stratum functionalis occur?

Proliferative Stage Signup and view all the answers

What is the main function of the corpus luteum in the ovarian cycle?

It produces oestrogen and progesterone. Signup and view all the answers

What is the chromosomal status of a secondary oocyte?

n – haploid Signup and view all the answers

During which phase does the primary oocyte complete meiosis?

If fertilized Signup and view all the answers

Which follicle stage contains a secondary oocyte and is characterized by an antrum?

Graafian follicle Signup and view all the answers

What process is involved in the development of oocytes from oogonia?

Mitosis followed by meiosis Signup and view all the answers

What is the role of the corpus luteum?

To secrete progesterone Signup and view all the answers

Which cells are present in a primary follicle?

Both B and C Signup and view all the answers

What happens to the polar bodies during oocyte development?

They disintegrate Signup and view all the answers

What characterizes the corpus albicans?

It is a degenerating corpus luteum Signup and view all the answers

Explain the relationship between the ovarian cycle and the stages of oocyte development.

The ovarian cycle involves ovarian follicles maturing and expelling a secondary oocyte during ovulation, which correlates with the different stages of oocyte development. Signup and view all the answers

Describe the role of meiosis in oocyte development and how it differs from spermatogenesis.

Meiosis in oocyte development results in the formation of one secondary oocyte and polar bodies, while spermatogenesis produces four viable sperm cells from one precursor. Signup and view all the answers

What happens to the first primary oocyte during a female's lifetime?

The primary oocyte undergoes mitotic division in utero to form oogonia and then stops at prophase I of meiosis until puberty. Signup and view all the answers

How do primordial germ cells contribute to oocyte quantity in females?

Primordial germ cells multiply by mitosis to create approximately 3 million oogonia, which eventually lead to the formation of primary oocytes. Signup and view all the answers

Identify the stages of meiosis that an oocyte undergoes from development to fertilization.

An oocyte completes meiosis I during ovulation and then arrests at metaphase II until fertilization occurs. Signup and view all the answers

What triggers ovulation and during which days of the menstrual cycle does this occur?

A surge of Luteinizing Hormone (LH) triggers ovulation, occurring around days 13-14 of the menstrual cycle. Signup and view all the answers

What happens to the stratum functionalis if no fertilization occurs during the menstrual cycle?

If no fertilization occurs, the stratum functionalis is shed during menstruation. Signup and view all the answers

How does Anti-Mullerian Hormone (AMH) affect the development of ovarian follicles?

Anti-Mullerian Hormone (AMH) prevents the development of surrounding primary follicles. Signup and view all the answers

What are the three histologically distinct stages of the menstrual cycle and their primary hormone influences?

The three stages are the Menstrual stage, Proliferative stage, and Secretory stage, regulated by ovarian steroids like estrogen and progesterone. Signup and view all the answers

What roles do estrogen and progesterone play in the Secretory stage of the menstrual cycle?

Estrogen and progesterone from the corpus luteum promote uterine receptivity and stimulate glandular secretions. Signup and view all the answers

What is the outcome of the secondary oocyte during fertilization?

If fertilized, the secondary oocyte completes Meiosis II and develops into an ovum. Signup and view all the answers

Identify the structural changes that occur in the corpus luteum.

The corpus luteum matures and secretes progesterone, preparing the endometrium for potential implantation. Signup and view all the answers

Describe the stages an oocyte undergoes from its initial development to ovulation.

An oocyte develops from oogonium to primary oocyte, then to secondary oocyte, culminating in ovulation. Signup and view all the answers

What differentiates a primary follicle from a secondary follicle?

A primary follicle contains a primary oocyte surrounded by granulosa cells, while a secondary follicle has a secondary oocyte and an antrum. Signup and view all the answers

What role do polar bodies play during oocyte development?

Polar bodies are byproducts of meiosis that disintegrate and help to ensure the secondary oocyte retains the majority of cytoplasmic material. Signup and view all the answers

Explain the significance of the Graafian follicle in the menstrual cycle.

The Graafian follicle represents a mature stage of follicular development and is responsible for releasing the secondary oocyte during ovulation. Signup and view all the answers

What happens to the corpus luteum if fertilization does not occur?

It degenerates into the corpus albicans, leading to a decline in progesterone levels. Signup and view all the answers

How does the oocyte's chromosomal status change from oogonium to secondary oocyte?

The oogonium is diploid (2n), the primary oocyte remains diploid during prophase I, and the secondary oocyte becomes haploid (n) after meiosis I. Signup and view all the answers

What are the three main layers of the uterus, and what distinguishes each one?

The three layers are the endometrium (inner layer with secretions), myometrium (middle muscle layer), and perimetrium (outer serous layer). Signup and view all the answers

Describe the anatomical position of the uterus in relation to the vagina.

The uterus is anteverted, meaning it tilts forward and is located anterior to the vertical plane going through the vagina. Signup and view all the answers

How does the cervix connect to the vagina, and what are its two openings called?

The cervix opens into the vagina, with the internal os being the opening from the cavity of the body and the external os being the opening into the vagina. Signup and view all the answers

What is the average length of the vagina in centimeters, and how does its structure facilitate its function?

The vagina is typically 8-10 cm long and has thin walls that allow it to expand during intercourse and childbirth. Signup and view all the answers

Identify the hilum of the ovary and its significance.

The hilum of the ovary contains blood vessels, nerves, and lymphatics that supply the ovary. Signup and view all the answers

What characterizes the endometrium during the menstrual cycle phases?

The endometrium undergoes changes such as proliferation and secretion during the menstrual cycle, specifically during the proliferative and secretory phases. Signup and view all the answers

Explain the importance of the myometrium in reproductive physiology.

The myometrium, composed mostly of smooth muscle, is important for the contractions that occur during labor and menstruation. Signup and view all the answers

What is the role of the peritoneum in the context of the cervix and vagina?

The peritoneum covers parts of the cervix and vagina, providing support and a protective layer in the pelvic cavity. Signup and view all the answers

Describe the anatomical feature of the fundus of the uterus.

The fundus is the top portion of the uterus located above the entrance of the uterine tubes. Signup and view all the answers

How do various clinical problems relate to the anatomy of the female reproductive tract?

Common clinical problems such as fibroids or endometriosis can directly affect structures like the uterus and ovaries, leading to pain and reproductive issues. Signup and view all the answers

What are the main hormones responsible for the regulation of ovarian function and what are their roles?

The main hormones are Follicle Stimulating Hormone (FSH) and Luteinizing Hormone (LH). FSH stimulates oocyte growth and estrogen secretion, while LH triggers ovulation and promotes the formation of the corpus luteum. Signup and view all the answers

Explain the sequence of events leading to ovulation during the ovarian cycle.

Ovulation occurs around day 14 of the cycle, initiated by an LH surge that results from hormonal changes, leading to the rupture of the Graafian follicle and release of the secondary oocyte. Signup and view all the answers

What happens to the remaining follicle after ovulation and what hormone does it produce?

After ovulation, the remaining follicle transforms into the corpus luteum, which produces progesterone and estrogen. These hormones are essential for preparing the endometrium for potential implantation. Signup and view all the answers

How does the feedback mechanism of oestrogens and inhibin influence FSH secretion during the ovarian cycle?

Oestrogens and inhibin exert negative feedback on the anterior pituitary to decrease FSH secretion, thereby preventing the maturation of additional follicles when one has already become dominant. Signup and view all the answers

What triggers the hormonal changes that lead to the LH surge before ovulation?

The rising levels of oestrogens from the growing follicles trigger the hypothalamus to release Gonadotropin-Releasing Hormone (GnRH), which stimulates the anterior pituitary to release LH. Signup and view all the answers

What role does the theca interna play in the ovarian cycle?

The theca interna cells produce androgens in response to LH, which are then converted to oestrogens by the granulosa cells stimulated by FSH. Signup and view all the answers

Describe the primary function of the corpus luteum in the menstrual cycle.

The corpus luteum primarily functions to secrete progesterone and estrogens, which are crucial for maintaining the endometrium and supporting early pregnancy if fertilization occurs. Signup and view all the answers

What distinguishes the dominant follicle during the ovarian cycle?

The dominant follicle is distinguished by its ability to rapidly acquire LH receptors, allowing it to respond more effectively to the LH surge compared to other follicles. Signup and view all the answers

Study Notes

Anatomy of the Female Reproductive Tract

The uterus is a pear-shaped muscular organ, 8 cm long, 5 cm wide, and 3 cm thick.
The uterus is anteverted, meaning it is anterior to a vertical plane going through the vagina.
The uterus has three layers: the endometrium (inner), myometrium (middle), and perimetrium (outer).
The cervix opens into the fornices of the vagina.
The fundus is the portion above the entrance of the uterine tubes.
The uterus is covered with peritoneum.

The Cervix

The isthmus is the area between the body and the cervix.
The isthmus is the supra vaginal portion of the cervix.
The posterior cervix is deeper and covered with peritoneum.
The internal os is the opening from the cavity of the body.
The external os is the opening into the vagina.

The Vagina

The vagina is a thin-walled tube, 8-10 cm long, that surrounds the cervix.
The vagina is normally anteverted and antiflexed.
The anterior fornix is shallow, and the anterior wall is shorter than the posterior wall.
The posterior fornix is deeper and covered with peritoneum in the pouch of Douglas, the lowest part of the peritoneal cavity.
The walls of the vagina are normally in contact except superiorly.

The Ovary

The ovary is responsible for oocyte development.
The ovarian cortex contains ovarian follicles in various stages of development.
Each follicle contains one oocyte.
From puberty to menopause, each month a mature (Graafian) follicle expels a secondary oocyte through ovulation.

Oogenesis

Oogenesis is the process of forming a secondary (2y) haploid (n) oocyte at ovulation.
Each embryonic ovary contains approximately 1000-2000 primordial germ cells.
Oogonia divide by mitosis to form around 3 million oogonia.
The sequence includes mitosis (in utero), meiosis I (after puberty each month), and meiosis II (at fertilization).
Oocytes develop in "follicles" with a visible sequence of follicular changes.
The follicular phase and luteal phase are defined by hormonal changes.

Follicle Development

Oogonia are stem cells.
Mitosis occurs in utero to form primary oocytes.
After puberty, meiosis I occurs each month.
Primary follicles develop into secondary follicles, then Graafian follicles.
The Graafian follicle releases a secondary oocyte during ovulation.

Follicular Stages

Primordial follicles contain a 1y oocyte and follicular cells.
Primary follicles contain a 1y oocyte, zona pellucida, theca interna and externa, and granulosa cells.
Secondary follicles (early antral/vesicular) contain a 1y oocyte.
Graafian follicles (vesicular) contain a 2y oocyte, antrum, follicular fluid, corona radiata, cumulus oophorius, and an ovulated oocyte.
Corpus luteum secretes progesterone.
Corpus albicans is a degenerating corpus luteum.

Ovulation

Ovulation is the rupture of the Graafian follicle and release of a 2y oocyte into the pelvic cavity.
Usually, only one oocyte is released.
Ovulation occurs around day 14 of the 28-day cycle due to hormonal changes causing an LH surge.
Increased volume and pressure of follicular fluid, enzymatic proteolysis of the follicular wall, and theca interna contraction contribute to ovulation.
The remaining follicle forms the corpus luteum.

Endocrine Regulation of Ovarian Function

Ovaries are responsible for oogenesis and the cyclic (~28 days) synthesis of steroidal estrogens and progesterone.
Principal events of the menstrual cycle in the uterus are correlated with events in the ovarian cycle and changes in the endometrium.
All events are hormonally controlled.

The Ovarian Cycle

The ovarian cycle is a monthly series of events associated with the maturation of an ovum.
The synthesis and secretion of estrogens from theca/granulosa cells and progesterone from the corpus luteum are regulated by the anterior pituitary gonadotrophins, LH, and FSH.

Follicle-Stimulating Hormone (FSH)

FSH stimulates the growth of granulosa cells and the initial development of primary ovarian follicles.
FSH stimulates the synthesis and secretion of estrogens and inhibin from granulosa cells (negative feedback).
FSH upregulates LH receptors in granulosa cells.
Many follicles may begin to mature during each cycle, but only one dominant follicle will mature to a secondary follicle.

Luteinizing Hormone (LH)

The dominant follicle that will ovulate is that which most rapidly acquires LH receptors.
LH stimulates later development of ovarian follicles.
An LH surge induces ovulation, peaking at day 13-14.
LH stimulates the production of estrogens via theca cells and progesterone by the corpus luteum.

Anti-Müllerian Hormone (AMH)

AMH is produced by granulosa cells.
AMH prevents the development of surrounding primary follicles.

The Menstrual Cycle

The menstrual cycle is a series of changes in the endometrium of the non-pregnant female.
The cycle is regulated by ovarian steroids.
Each month, the endometrium (stratum basalis and stratum functionalis) prepares to nourish and receive a fertilized ovum.
If no fertilization occurs, the stratum functionalis is shed (menstruation).
There are three histologically distinct stages in women: menstrual, proliferative, and secretory.

Ovarian Steroid Regulation

Menstrual stage: Shedding of the stratum functionalis occurs when progesterone from the corpus luteum is lost.
Proliferative stage: Ovarian estrogens promote proliferation and repair of the stratum functionalis.
Secretory stage: Estrogen and progesterone from the corpus luteum promote uterine receptivity and glandular secretions.

Female Reproductive Tract Anatomy

The female reproductive tract includes the bladder, urethra, uterus, ovaries, vagina, and rectum.

Uterus

The uterus is a pear-shaped muscular organ.
The uterus is anteverted, meaning it lies anterior to the vertical plane going through the vagina.
It is approximately 8 cm long, 5 cm wide, and 3 cm thick.
The cervix of the uterus opens into the fornices of the vagina.
The fundus is the portion of the uterus above the entrance of the uterine tubes.
The uterus is covered with peritoneum.

Uterine Histology

The uterine wall has three layers: endometrium, myometrium, and perimetrium.
The endometrium is the inner lining of the uterus and is composed of glandular cells that secrete.
The myometrium is the thickest middle layer of the uterus and consists mainly of smooth muscle.
The perimetrium is the outer serous layer of the uterus.

Cervix

The isthmus is a circular area between the body and cervix.
The isthmus is the supra vaginal portion of the cervix and the lower uterine segment.
The posterior cervix is deeper than the anterior cervix and is covered with peritoneum.
The internal os is the opening from the cavity of the body of the uterus into the cervix.
The external os is the opening of the cervix into the vagina.

Vagina

The vagina is a thin-walled tube that surrounds the cervix, approximately 8-10 cm long.
It is normally anteverted and antiflexed.
The anterior fornix is shallow and the anterior wall of the vagina is shorter than the posterior wall.
The posterior fornix is deeper and is covered with peritoneum of the pouch of Douglas, which is the lowest part of the peritoneal cavity.
The walls of the vagina are normally in contact except superiorly.

Ovary

The ovaries are the sites of oocyte development.
The ovarian cortex contains ovarian follicles in various stages of development.
Each follicle contains one oocyte.
The appearance of the ovaries varies with age and stage in the monthly cycle.