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Questions and Answers
What is the primary reproductive function of the ovaries?
What is the primary reproductive function of the ovaries?
Which hormone is primarily responsible for preparing the endometrium for pregnancy?
Which hormone is primarily responsible for preparing the endometrium for pregnancy?
At what stage of embryonic development does the migration of primordial germ cells occur?
At what stage of embryonic development does the migration of primordial germ cells occur?
What covers the surface of the ovary?
What covers the surface of the ovary?
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How many primary oocytes remain at birth?
How many primary oocytes remain at birth?
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Which type of follicle is NOT considered a stage of ovarian follicle development?
Which type of follicle is NOT considered a stage of ovarian follicle development?
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What typically happens to the majority of primary oocytes by birth?
What typically happens to the majority of primary oocytes by birth?
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What is the inner region of the ovary called?
What is the inner region of the ovary called?
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What do granulosa cells develop during follicular growth?
What do granulosa cells develop during follicular growth?
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What is the name of the fluid that accumulates among granulosa cells to form the antrum?
What is the name of the fluid that accumulates among granulosa cells to form the antrum?
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What are the two layers that the theca follicle differentiates into?
What are the two layers that the theca follicle differentiates into?
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What role do androgens play in the ovarian follicle?
What role do androgens play in the ovarian follicle?
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What happens as the stratum granulosum reaches 6 to 12 cell layers?
What happens as the stratum granulosum reaches 6 to 12 cell layers?
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During the menstrual cycle, how is the dominant follicle characterized?
During the menstrual cycle, how is the dominant follicle characterized?
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What substance do granulosa cells use to convert androgen to estrogen?
What substance do granulosa cells use to convert androgen to estrogen?
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What distinguishes the theca interna from the theca externa?
What distinguishes the theca interna from the theca externa?
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What is primarily found in the follicular fluid?
What is primarily found in the follicular fluid?
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What promotes the proliferation of granulosa cells?
What promotes the proliferation of granulosa cells?
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How many mature ova does a woman produce during her reproductive lifespan?
How many mature ova does a woman produce during her reproductive lifespan?
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What is the definition of a follicle in the context of ovarian biology?
What is the definition of a follicle in the context of ovarian biology?
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At what stage of intrauterine life do primordial follicles first appear in the ovaries?
At what stage of intrauterine life do primordial follicles first appear in the ovaries?
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What hormonal stimulation is required for the further development of primordial follicles after puberty?
What hormonal stimulation is required for the further development of primordial follicles after puberty?
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What is the location of primordial follicles within the ovary?
What is the location of primordial follicles within the ovary?
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What is the composition of zona pellucida in human primary follicles?
What is the composition of zona pellucida in human primary follicles?
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Which component is identified as a spermatozoa-binding receptor in zona pellucida?
Which component is identified as a spermatozoa-binding receptor in zona pellucida?
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What type of cells surround the oocyte in an early primary follicle?
What type of cells surround the oocyte in an early primary follicle?
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Which of the following describes the Balbiani body found in the oocyte?
Which of the following describes the Balbiani body found in the oocyte?
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What happens to granulosa cells during the late primary follicle stage?
What happens to granulosa cells during the late primary follicle stage?
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What is the primary responsibility of the placenta after 6 weeks of pregnancy?
What is the primary responsibility of the placenta after 6 weeks of pregnancy?
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What is primarily responsible for the symptoms of 'morning sickness' in early pregnancy?
What is primarily responsible for the symptoms of 'morning sickness' in early pregnancy?
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Which of the following is NOT a step in follicular atresia?
Which of the following is NOT a step in follicular atresia?
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What characterizes hilus cells in the ovary?
What characterizes hilus cells in the ovary?
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Ovarian cysts are primarily diagnosed through which method?
Ovarian cysts are primarily diagnosed through which method?
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What is the role of the cumulus oophorus during ovulation?
What is the role of the cumulus oophorus during ovulation?
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During which phase of the menstrual cycle does ovulation typically occur?
During which phase of the menstrual cycle does ovulation typically occur?
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What transformation happens to the follicular wall after ovulation?
What transformation happens to the follicular wall after ovulation?
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What hormone primarily secreted by the corpus luteum is crucial for maintaining early pregnancy?
What hormone primarily secreted by the corpus luteum is crucial for maintaining early pregnancy?
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What is the significance of the stigma formed before ovulation?
What is the significance of the stigma formed before ovulation?
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What defines the corona radiata?
What defines the corona radiata?
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What happens to other developing follicles during the process of atresia?
What happens to other developing follicles during the process of atresia?
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What role do spermatozoa play if sexual intercourse occurs near ovulation?
What role do spermatozoa play if sexual intercourse occurs near ovulation?
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What is a characteristic feature of the Graafian follicle at the time of ovulation?
What is a characteristic feature of the Graafian follicle at the time of ovulation?
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What happens to the blood flow in the tissue surrounding the mature follicle just before ovulation?
What happens to the blood flow in the tissue surrounding the mature follicle just before ovulation?
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What is the primary function of the female reproductive system during the menstrual cycle?
What is the primary function of the female reproductive system during the menstrual cycle?
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Which of the following pairs are internal organs of the female reproductive system?
Which of the following pairs are internal organs of the female reproductive system?
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How does the corpus luteum function in the female reproductive system?
How does the corpus luteum function in the female reproductive system?
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What characteristic distinguishes between a corpus luteum of menstruation and a corpus luteum of pregnancy?
What characteristic distinguishes between a corpus luteum of menstruation and a corpus luteum of pregnancy?
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What kind of changes occur in the female reproductive system between menarche and menopause?
What kind of changes occur in the female reproductive system between menarche and menopause?
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What distinguishes an atretic follicle from a corpus albicans?
What distinguishes an atretic follicle from a corpus albicans?
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Which structure primarily nourishes and transports the ovum post-ovulation?
Which structure primarily nourishes and transports the ovum post-ovulation?
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Which of the following statements about Graafian follicles is true during ovulation?
Which of the following statements about Graafian follicles is true during ovulation?
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What type of epithelium lines the oviduct?
What type of epithelium lines the oviduct?
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Which cells in the oviduct produce the fluid that nourishes the ovum?
Which cells in the oviduct produce the fluid that nourishes the ovum?
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What happens to ciliated cells during luteolysis?
What happens to ciliated cells during luteolysis?
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Which layer of the oviduct is composed of smooth muscle tissue?
Which layer of the oviduct is composed of smooth muscle tissue?
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What anatomical features distinguish the four regions of the oviduct?
What anatomical features distinguish the four regions of the oviduct?
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What differentiates the corpus luteum from the corpus albicans?
What differentiates the corpus luteum from the corpus albicans?
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What is the primary hormone secreted by granulosa lutein cells?
What is the primary hormone secreted by granulosa lutein cells?
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What initiates the continuation of progesterone secretion from the corpus luteum after fertilization?
What initiates the continuation of progesterone secretion from the corpus luteum after fertilization?
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What role does progesterone NOT play in the female reproductive system?
What role does progesterone NOT play in the female reproductive system?
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What happens to the corpus luteum if the ovum is not fertilized?
What happens to the corpus luteum if the ovum is not fertilized?
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What is one of the features of steroid-secreting cells, such as luteal cells?
What is one of the features of steroid-secreting cells, such as luteal cells?
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What primary feature defines the corpus luteum graviditatis?
What primary feature defines the corpus luteum graviditatis?
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The degeneration of the corpus luteum results in which of the following?
The degeneration of the corpus luteum results in which of the following?
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Which type of corpus luteum is characterized by its temporary existence and brief hormone secretion?
Which type of corpus luteum is characterized by its temporary existence and brief hormone secretion?
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What is the role of estrogens in female development?
What is the role of estrogens in female development?
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What characterizes the outer cortex of the ovary?
What characterizes the outer cortex of the ovary?
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At what point in embryonic development do oogonia begin to differentiate into primary oocytes?
At what point in embryonic development do oogonia begin to differentiate into primary oocytes?
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What is the predominant stage of oocyte development upon birth?
What is the predominant stage of oocyte development upon birth?
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What is the function of the corpus luteum after ovulation?
What is the function of the corpus luteum after ovulation?
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What defines the structure of a primordial follicle?
What defines the structure of a primordial follicle?
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What describes the typical outcome of ovarian follicle development during a menstrual cycle?
What describes the typical outcome of ovarian follicle development during a menstrual cycle?
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What occurs to the ovarian follicles during the process of atresia?
What occurs to the ovarian follicles during the process of atresia?
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What is the significance of the 'stigma' formed before ovulation?
What is the significance of the 'stigma' formed before ovulation?
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What typically happens to primary oocytes that do not mature?
What typically happens to primary oocytes that do not mature?
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What is the role of gonadotropins in ovarian follicle development post-puberty?
What is the role of gonadotropins in ovarian follicle development post-puberty?
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Which structure is essential for the process of sperm binding during fertilization?
Which structure is essential for the process of sperm binding during fertilization?
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How does the composition of the zona pellucida change during follicular development?
How does the composition of the zona pellucida change during follicular development?
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What is the ancestral origin of primordial follicles in the ovaries?
What is the ancestral origin of primordial follicles in the ovaries?
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What defines the primary oocyte within a primordial follicle?
What defines the primary oocyte within a primordial follicle?
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What is included in the structure of the Balbiani body located in the oocyte?
What is included in the structure of the Balbiani body located in the oocyte?
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Which of the following stages characterizes a growing follicle?
Which of the following stages characterizes a growing follicle?
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Where are primordial follicles primarily located within the ovary?
Where are primordial follicles primarily located within the ovary?
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Which oocyte stage is prevalent until the onset of puberty?
Which oocyte stage is prevalent until the onset of puberty?
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Study Notes
Ovary Location and Function
- Located in the broad ligament
- Produces gametes (ova) - reproductive function
- Secretes female sex hormones (estrogens and progesterone) - endocrine function
Estrogen
- Promotes growth and maturation of female sex organs and sex characteristics
- Stimulates ductal and stromal growth in mammary glands leading to breast development
Progesterone
- Prepares the internal sex organs for pregnancy by promoting secretory changes in the endometrium
- Prepares the mammary glands for lactation
Ovarian Structure
- Surface covered by a single layer of simple cuboidal epithelium (germinal epithelium)
- Thin capsule called tunica albuginea formed by connective tissue (CT)
- Divided into outer cortex (CT stroma containing ovarian follicles ) and inner medulla (loose CT containing blood vessels and nerves)
Early Ovarian Development
- During the first month of embryonic life, primordial germ cells migrate from the yolk sac to the gonadal primordia.
- These cells differentiate as oogonia.
- Oogonia divide by mitosis for the next few months, and some differentiate into primary oocytes.
- By the 3rd month, oogonia enter the prophase of the first meiotic division.
- By the 5th month of development, there are around 7 million primary oocytes, but most degenerate by birth.
- The remaining primary oocytes are surrounded by a single layer of squamous epithelial cells (follicle cells), forming a primordial follicle.
- Degeneration of primary oocytes continues throughout life.
- At birth, there are approximately 1 million primordial follicles.
- At puberty around 300,000 primordial follicles remain.
Ovarian Follicles
- Provide the microenvironment for the developing oocyte
- Vary in size, each containing a single oocyte.
- Size of follicle indicates the developmental state of the oocyte.
- Only one oocyte typically reaches full maturity.
- Maturation and release of multiple eggs at ovulation can lead to multiple zygotes.
- During a woman’s reproductive lifespan, only about 400 mature ova are produced.
Types of Ovarian Follicles
- Primordial follicle
- Growing follicles: primary and secondary
- Mature, dominant follicle or Graafian follicle
Primordial Follicles
- First appear in the ovaries during the 3rd month of intrauterine life (IUL).
- By the 7th month of IUL, all oogonia are transformed into primary oocytes.
- Early growth of the primordial follicles is independent of gonadotropin stimulation.
- Oocyte remains in this stage until puberty and further development occurs after puberty under the influence of gonadotropins (FSH and LH) secreted by the anterior pituitary.
- Located in the peripheral part of the cortex.
- Consists of an oocyte in prophase of the first meiotic division surrounded by a single layer of squamous follicle cells.
- Outer surface of the follicle cells is bounded by a basal lamina.
- Cytoplasm of the oocyte, referred to as ooplasm, contains a Balbiani body and annulate lamellae.
Balbiani Body
- Localized accumulation of Golgi membranes and vesicles, ER, centrioles, numerous mitochondria, and lysosomes.
Annulate Lamellae
- Resemble a stack of nuclear envelope profiles
- Each layer includes pore structures morphologically identical to nuclear pores.
Early Primary Follicle
- Consists of the oocyte surrounded by a single layer of cuboidal or columnar follicular cells (early, or unilaminar primary) follicle.
- Homogeneous, acidophilic refractive layer called zona pellucida (glycoproteins between the oocyte and granulosa cells) becomes visible.
- Zona pellucida is secreted by the growing oocyte and follicular cells.
- Composed of ZP glycoproteins: ZP-1, ZP-2, and ZP-3
- ZP-3 is the spermatozoa-binding receptor and inducer of the acrosome reaction.
Late Primary Follicle
- Continued proliferation of granulosa cells leads to the formation of a stratified epithelium surrounding the oocyte (multilaminar primary follicle).
- Follicular cells multiply to form membrane granulosa cells (stratum granulosum).
- Granulosa cells (renamed follicular cells) contain granulosa cells.
- Gap junctions develop between granulosa cells during follicular growth.
- Movement of nutrients and macromolecules from the blood into the follicular fluid is essential for normal development of the follicle.
- Surrounding stromal CT cells surrounding the follicle form concentric sheaths called theca folliculi.
Secondary Follicles
- When the stratum granulosum reaches 6 to 12 cell layers, fluid-filled cavities appear among the granulosa cells.
- Hyaluronan-rich follicular fluid (liquor folliculi) accumulates among the granulosa cells, the cavities coalesce, forming a single cavity called the antrum.
- The follicle is now identified as a secondary or antral follicle.
- Follicular fluid contains high concentrations of steroids (progesterone, androstenedione, and estrogens) with binding proteins.
- The oocyte is located eccentrically and surrounded by granulosa cells.
Theca Follicle
- Differentiates into 2 layers: inner theca interna and outer theca externa.
- Distinct basement membrane separates the granulosa cells from the theca interna.
-
Theca Interna:
- Highly vascularized layer of cuboidal secretory cells.
- Possesses a large number of luteinizing hormone (LH) receptors.
- Synthesize and secrete androgens in response to LH stimulation.
- Androgens serve as precursors of estrogens.
-
Theca Externa:
- Contains CT cells, smooth muscle cells, and bundles of collagen fibers.
Estrogen Production
- LH (adenohypophysis) stimulates the cells of the theca interna to secrete androgens, which serve as estrogen precursors.
- Androgens are transported to the granulosa cells.
- FSH (adenohypophysis) stimulates the granulosa cells to catalyze the conversion of androgens to estrogens (enzyme aromatase).
- Estrogens stimulate the granulosa cells to proliferate, increasing the size of the follicle.
Mature (Tertiary, Preovulatory, Graafian) Follicle
- One follicle grows more than others, becoming mature (dominant) during each menstrual cycle.
- While other developing follicles undergo atrophy (atresia).
- Cavities form a single large antrum.
- Oocyte is displaced to one side of the follicle.
- A few layers of follicular cells that immediately surround the oocyte are called the corona radiata.
- Some of the follicular cells concentrate at one point, projecting into the antrum; these cells are called the cumulus oophorus.
Ovulation
- Hormone-mediated (LH) process of liberation of the secondary oocyte by the rupture of the Graafian follicle into the peritoneal cavity.
- Takes place in the middle of the menstrual cycle, on the 14th day of a 28-day cycle.
- Secondary oocyte (not ovum yet) and its corona radiata cells leave the ruptured follicle at the ovarian surface and enter the fimbriated end of the oviduct.
Ovulation Process
- In the hours before ovulation, the large mature follicle bulging against the tunica albuginea develops a whitish or translucent ischemic area, the stigma, in which compaction of the tissue has blocked blood flow.
Ovulation and Fertilization
- If sexual intercourse takes place around the time of ovulation, spermatozoa deposited in the vagina swim into the uterus and into the uterine tube.
- One spermatozoa may fertilize the secondary oocyte.
- Ovulation should not be used as the only method of contraception - it is very unreliable.
Corpus Luteum (Yellow Body)
- After ovulation, the follicular wall, composed of the granulosa and theca cells, transforms into the temporary endocrine gland called corpus luteum (luteal gland).
- Corpus luteum secretes mainly progesterone.
- It is named after the Latin word "luteus", meaning "saffron-yellow".
Development of the Corpus Luteum
- Includes four stages: proliferation and vascularization, luteinization, secretory stage, and regression.
- In the proliferation and vascularization stage, cells of the granulosa and theca interna proliferate; blood vessels from theca interna rapidly grow into the granulosa layer.
- Luteinization is the process of transformation of granulosa cells into granulosa lutein cells and theca interna cells into theca lutein cells.
- During the secretory stage, the corpus luteum secretes progesterone and estrogens; the corpus luteum reaches its maximum size after 8 to 10 days.
- Regression occurs if pregnancy does not occur after 10 to 12 days, and the corpus luteum begins to degenerate and forms a corpus albicans.
hCG
- Detection of hCG in the serum is possible as early as 6 days after conception.
- Detection of hCG in the urine occurs between 10 to 14 days of pregnancy.
- Detection of hCG in urine by specific antibodies is the basis for most over-the-counter pregnancy tests.
- Rapid increase in hCG levels in early pregnancy causes “morning sickness”, characterized by nausea and vomiting.
Follicular Atresia
- Programmed destruction of follicles in apoptosis.
- Most ovarian follicles degenerate and undergo follicular atresia.
- Events in follicular atresia:
- Initiation of apoptosis by granulosa cells
- Autolysis of granulosa cells by proteolytic enzymes
- Hypertrophy of theca interna cells
- Replacement of follicular cells by CT
- Macrophages remove degenerating follicular cells, oocyte, and ZP by phagocytosis.
- Characteristic of degenerating follicle: basement membrane separating theca interna and granulosa cells become thick to form a wavy hyaline glassy membrane.
Hilus Cells (Hilar Cells)
- Arranged in clusters within the hilum area
- Shape: ovoid to polygonal (polyhedral)
- Nucleus: 1 spherical (eccentrically located)
- Cytoplasm staining: eosinophilic (high intensity)
- Contain Reinke's crystalloids (resembling interstitial endocrine cells of Leydig in the testes)
- These cells enzymatically produce androgens from estrogens
- Originate from fibroblasts
- Hyperplasia or tumors associated with these cells usually lead to masculinization
Clinical Correlation
- Ovarian cysts are fluid-filled sacs (>2 cm in diameter) that typically arise from epithelial components of the ovary, mostly Graafian follicles.
- Usually benign and asymptomatic.
- They commonly occur in reproductive-age women; diagnosis is by palpation, ultrasonography, or pelvic computed tomography.
Female Reproductive System
- The female reproductive system (FRS) consists of internal organs (ovaries, uterine tubes, uterus, and vagina) located in the pelvis and external genitalia (mons pubis, labia majora and minora, clitoris, vestibule, and external urethral opening) located in the perineum.
- Accessory sex glands include the mammary gland, Skene’s glands, Bartholin's glands, and pregnancy-related structures such as placenta and umbilical cord.
Functions of the Female Reproductive System
- The FRS is responsible for the maturation, release, and transportation of female gametes (oocytes).
- It facilitates sexual intercourse, provides a suitable environment for fertilization, and supports embryonic development.
- It contributes to childbirth through labor.
- It produces sex hormones (estrogens and progesterone) regulated by the hypothalamic-pituitary axis.
- These hormones trigger cyclical morphological and functional changes in female genital organs between menarche and menopause.
Ovary
- The ovaries are paired female gonads, almond-shaped, pinkish-white organs located in the broad ligament.
- They serve as the primary reproductive organs, producing gametes (ova) and secreting female sex hormones (estrogens and progesterone).
Female Sex Hormones
- Estrogens promote the growth and maturation of female sex organs during puberty and stimulate breast development.
- Progesterone prepares internal sex organs for pregnancy, including the endometrium for implantation and the mammary glands for lactation.
Ovarian Structure
- The ovary is covered by simple cuboidal epithelium (germinal epithelium) and a thin capsule called tunica albuginea.
- It is divided into an outer cortex (containing ovarian follicles in CT stroma) and an inner medulla (loose CT with blood vessels and nerves).
Early Ovarian Development
- Primordial germ cells migrate from the yolk sac to the gonadal primordia during the first month of embryonic life and differentiate as oogonia.
- Oogonia divide mitotically followed by differentiation into primary oocytes.
- By the third month, oogonia enter prophase of the first meiotic division but do not progress further.
- By the fifth month, around 7 million primary oocytes exist, but most degenerate before birth.
- Those that remain are surrounded by a single layer of squamous cells (follicle cells) forming a primordial follicle.
- Degeneration continues, leaving 1 million primordial follicles at birth and about 300,000 at puberty.
Ovarian Follicles
- The ovarian cortex displays various stages of developing follicles, including primordial, primary, secondary, Graafian, corpus luteum, corpus albicans, and atretic follicles.
- Follicles provide a microenvironment for developing oocytes, with size indicating developmental stage.
- Although multiple follicles develop, typically only one reaches full maturity.
- During reproductive life, a woman produces approximately 400 mature ova.
Follicle Development
- A follicle consists of one oocyte and surrounding follicular cells.
- Categories include primordial, growing (primary and secondary), and mature, dominant (Graafian) follicles.
Primordial Follicles
- These appear in the ovaries during the third month of intrauterine life.
- By the seventh month, all oogonia transform into primary oocytes.
- Early growth is independent of gonadotropin stimulation.
- Oocyte remains in this stage until puberty, where further development is stimulated by gonadotropins (FSH and LH) from the anterior pituitary.
Primordial Follicle Structure
- Located in the peripheral cortex, consisting of an oocyte in prophase of the first meiotic division surrounded by a single layer of squamous follicle cells.
- The outer surface is bounded by a basal lamina.
- The oocyte's cytoplasm (ooplasm) contains a Balbiani body and annulate lamellae.
Balbiani Body
- This is a localized accumulation of Golgi membranes and vesicles, ER, centrioles, mitochondria, and lysosomes.
Annulate Lamellae
- These resemble stacks of nuclear envelope profiles with pore structures similar to nuclear pores.
Early Primary Follicle
- Consists of an oocyte surrounded by a single layer of cuboidal or columnar follicular cells (unilaminar primary follicle).
- A homogeneous, acidophilic refractive layer called the zona pellucida (glycoproteins between the oocyte and granulosa cells) becomes visible.
- The zona pellucida is secreted by the growing oocyte and follicular cells.
- In humans, it is composed of ZP glycoproteins (ZP-1, ZP-2, and ZP-3).
- ZP-3 is the sperm-binding receptor that induces the acrosome reaction.
Late Primary Follicle
- Continued granulosa cell proliferation leads to stratified epithelium surrounding the oocyte (multilaminar primary follicle).
- The theca interna (luteal cells) increase in size and become filled with yellow pigment (lutein), exhibiting steroid-secreting cell features (abundant sER and mitochondria).
Development of the Corpus Luteum
- The corpus luteum develops from the ruptured Graafian follicle after ovulation.
- Granulosa lutein cells (derived from granulosa cells) secrete progesterone and inhibin.
- Theca lutein cells (derived from theca interna cells) secrete androgens, estrogens, and progesterone.
- Progesterone stimulates endometrial growth and secretory activity, preparing it for implantation.
Effects of Progesterone
- Inhibits the release of LHRH from the hypothalamus and LH from the anterior pituitary.
- Promotes the development of the uterine endometrium.
- Regulates cervical mucus viscosity.
- Contributes to female sexual characteristics, including breast development.
- Suppresses T cell-mediated fetal rejection.
Degeneration of the Corpus Luteum
- The corpus luteum degenerates after pregnancy or menstruation, forming a white scar called the corpus albicans.
- The corpus albicans disappears slowly within several months.
Types of Corpus Luteum
- If the oocyte is not fertilized, the corpus luteum remains for 14 days in a 28-day cycle, called the menstrual corpus luteum.
- If the oocyte is fertilized and implantation occurs, trophoblast cells of the blastocyst secrete human chorionic gonadotrophin (HCG).
- HCG signals the corpus luteum to continue progesterone secretion, maintaining the endometrium and supporting zygote development.
- This is called the corpus luteum graviditatis (corpus luteum of pregnancy).
Corpus Luteum Graviditatis (Pregnancy)
- In early pregnancy, the corpus luteum measures 2 to 3 cm, filling a large portion of the ovary.
- Its function starts to decline gradually after 8 weeks of pregnancy, but it persists throughout pregnancy.
Oviduct (Fallopian Tube)
- The oviduct is divided into four regions: infundibulum, ampulla, isthmus, and intramural portion.
Oviduct Structure
- The oviduct consists of three layers: mucosa, muscularis, and serosa.
- The mucosa contains longitudinal folds and a simple columnar epithelium with two cell types: ciliated cells (cilia beat toward the uterus) and non-ciliated, secretory peg cells (produce nutritive fluid for the ovum).
- The lamina propria is loose connective tissue.
- The muscularis has an outer longitudinal and inner circular smooth muscle layer.
- The serosa is covered by mesothelium.
Oviduct Epithelium
- The epithelium is under hormonal control.
- Ciliated cells enlarge and produce cilia during follicle development and estrogen production.
- Estrogens increase ciliary beat rate.
- During luteolysis (regression of the corpus luteum), ciliated cells lose cilia (deciliation).
- The secretory activity of the non-ciliated peg cells is also stimulated by estrogens, providing nutrients for the egg during its migration.
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Test your knowledge on the location and functions of the ovaries, including their role in gamete production and hormone secretion. This quiz also covers the structure of the ovaries and the development during embryonic life.
