Histology of the female reproductive tract Flashcards
What are the two related functions of the ovary?
- Produce gametes (termed oogenesis in females)
- Produce steroids, mainly oestrogens and progestogens (mainly progesterone)
The ovary has a ______ and a ______
The ______ forms the core of the organ and contains ______ ________ _____, contorted ______, ____ and _______.
The ________ is continuous with the hilum of the organ.
The ovary has a medulla and a cortex
The medulla forms the core of the organ and contains loose connective tissue, contorted arteries, veins and lymphatics.
The medulla is continuous with the hilum of the organ.
The cortex has scattered ______ ______ in a highly cellular ______ ______ stroma.
The outer shell of the cortex is a ______ _______ tissue layer called the _______ _______.
The cortex has scattered ovarian follicles in a highly cellular connective tissue stroma.
The outer shell of the cortex is a dense connective tissue layer called the tunica albuginea.
What covers the tunica albuginea?
Single layer of cuboidal cells called the germinal epithelium
List the stages of development from primordial follicle to corpus albicans
- primordial follicle
- early primary follicle
- late primary follicle
- secondary follicle
- follicle approaching maturity
- mature graafian follicle
- ruptured follicle
- corpus haemorrhagicum
- corpus luteum
- corpus albicans
What enters the hilum of the ovary from the broad ligament?
The helicine arteires- supply blood to the organ
Early in embryonic development (around ____ _) _____ cells from the yolk sac invade the _______ and proliferate by _______ to form _____. These cells will undergo development and division via ______ to form mature _____, which are also termed ___.
Early in embryonic development (around week 6) germ cells from the yolk sac invade the ovaries and proliferate by mitosis to form oogonia. These cells will undergo development and division via meiosis to form mature oocytes, which are also termed ova.
What is oogenesis?
Development of oocytes, the female germ cells, from oogonia.
What is folliculogenesis?
Growth of the follicle, which consists of the oocyte and any associated support cells.
What is atresia?
Loss of oogonia and oocytes- an apoptotic process.
The cell is resorbed following death.
Before birth ______ begins in the ______, but halts in ______ _. IF the oocyte undergoes further development, ______ will restart, but many will reman in this state for decades.
Before birth meiosis begins in the oocytes, but halts in prophase I. IF the oocyte undergoes further development, meiosis will restart, but many will reman in this state for decades.
When will an oocyte die?
If it fails to associate with pregranulosa (follicle cells)
As the follicle enters the growth phase the pregranulosa cells change from ______ –> ______
As the follicle enters the growth phase the pregranulosa cells change from squamous –> cuboidal
What defines primary follicles?
Cuboidal granulosa cells: zona granulosa
What do stromal cells associating with the outside of the primary follicle go on to form?
Theca Folliculi
What forms between the oocyte and the granulosa cells ?
Zona pellucida
Inner layers of the stromal cells (theca folliculi) transform into a layer called the ____ _______, which will go on to secrete ______ precursors which will be converted to _______ by the ______ ______. The outer layers remain _______-like and form the ____ ______.
Inner layers of the stromal cells (theca folliculi) transform into a layer called the theca interna, which will go on to secrete oestrogen precursors which will be converted to oestrogen by the granulosa cells. The outer layers remain fibroblast-like and form the theca externa.
As the follicle enlarges, a space, called the ______ (_), filled with _______ _____ begins to form and enlarge in the _______ ___ _____ (__), forming a secondary follicle.
As the follicle enlarges, a space, called the antrum (A), filled with follicular fluid begins to form and enlarge in the granulosa cell layer (GC), forming a secondary follicle.
Overall the follicle enlarges as the ______ enlarges, and the _______ and _____ layers (____ ______, TI, and ____ ______, TE) continue to ________.
Overall the follicle enlarges as the antrum enlarges, and the granulosa and thecal layers (theca interna, TI, and theca externa, TE) continue to proliferate.
What are the largest antral follicles?
Graafian follicles- can reach 20mm in diameter
___ day before ovulation, the _____ in the ______ Graafian follicle will complete _____ _, but instead of producing two equal cells, it will produce ___ ____ called a _______ ______, similar in size to the ______ ______ _____, and one tiny _____ ____ that carries the ______ ______ away to degenerate. The secondary oocyte will then begin the second phase of _______, but will stop at _______ __.
One day before ovulation, the oocyte in the largest Graafian follicle will complete meiosis 1, but instead of producing two equal cells, it will produce one cell called a secondary oocyte, similar in size to the original primary oocyte, and one tiny polar body that carries the second nucleus away to degenerate. The secondary oocyte will then begin the second phase of meiosis, but will stop at metaphase II.
When will a secondary oocyte complete meiosis?
When it has been released and fertilised by a sperm- producing a second polar body
After ovulation the follicle transforms into a _____ _____ with the ____ and ________ cells secreting _________ and _________, which helps prepare the uterus for _________.
After ovulation the follicle transforms into a corpus luteum with the theca and granulosa cells secreting oestrogens and progesterone, which helps prepare the uterus for implantation.
Assuming no implantation occurs, the _____ _____ will become a white coloured connective tissue called the _____ _____.
If implantation occurs, the placenta secretes ___ which prevents degeneration of the ______ ______ for a time and so maintains __________ levels, which in turn maintains the ________.
Assuming no implantation occurs, the corpus luteum will become a white coloured connective tissue called the corpus albicans.
If implantation occurs, the placenta secretes HCG which prevents degeneration of the corpus luteum for a time and so maintains progesterone levels, which in turn maintains the pregnancy.
The funnel shaped _________ moves so that its ______ is adjacent to the site where the follicle _______.
The ____ moves down the tube propelled by _____ ______ and currents created by the ______ ______.
The funnel shaped infundibulum moves so that its opening is adjacent to the site where the follicle ruptures.
The ovum moves down the tube propelled by gentle peristalsis and currents created by the ciliated epithelium.
Where do nutrients come from in the uterine tubes?
Secretory cells in the epithelium
Where does fertilisation occur?
In the ampulla
Describe the mucosa in the ampulla of the uterine tube?
Highly folded and lined by simple columnar epithelium with ciliated cells and secretory cells.
What surrounds the mucosa of the uterine tube?
Smooth muscle
In the uterine tube what is cyclic?
Secretion and ciliogenesis
What is the lining of the isthmus of the uterine tube like?
Much simpler
Mostly secretory with a few ciliated cells
There are said to be _ layers of smooth muscle in the ______ and _ layers in the ______.
There are said to be 2 layers of smooth muscle in the ampulla and 3 layers in the isthmus.
What makes up the uterine wall?
Endometrium
Myometrium
Perimetrium
What is the endometrium
Inner layer of secretory mucosa
Shed during menstruation
Tubular secretory glands embedded in connective tissue stroma
What is the myometrium?
Coat of 3 layers of smooth muscle combined with collagen and elastic tissue
What is the perimetrium?
Outer visceral covering of loose connective tissue covered by mesothelium
What is the endometrium divided into?
Stratum functionalis and stratum basalis
What is the stratum functionalis?
Undergoes monthly growth, degeneration and loss.
What is the stratum basalis?
Reserve tissue that regenerates the functionalis
What supplies the endometrium with blood
Uterine artery–> arcuate artery –> radial branch –> straight artery –> spiral artery
During the ________ _____ the stratum ______ proliferates and ______, ______ and ________ grow.
This increases the _______ of the endometrium by _________ the stratum __________.
During the proliferative phase the stratum basalis proliferates and glands, stroma and vasculature grow.
This increases the thickness of the endometrium by reconstituting the stratum functionalis.
When does the proliferative phase continue until?
About one day after ovulation from day 5 of cycle
How will the lining of the uterus appear during the proliferative phase?
Pseudostratified columnar epithelium lines glands which are relatively straight.
What happens to glands durng secretory phase?
The glands become coiled with corkscrew appearance and secrete glycogen.
What happens in the menstrual phase?
Arterioles in the stratum functionalis undergo constriction, depriving tissue of blood and causing ischaemia, with resultant tissue breakdown, leakage of blood and tissue sloughing.
The cervix is a short cylinder with a small _____ that projects into the _____ _____. It is mostly _____ _________ tissue covered by stratified squamous epithelium on its ______ surface, but transitioning to _______ ______ _____ ________ epithelium.
The cervix is a short cylinder with a small lumen that projects into the upper vagina. It is mostly fibrous connective tissue covered by stratified squamous epithelium on its vaginal surface, but transitioning to mucous secreting simple columnar epithelium.
What is a common problem in the transition zone?
Common site of dysplasia, and neoplastic changes leading to cervical cancer
Describe the mucus secreting epithelium of the cervical canal?
Deeply furrowed, forming glands- endocervical glands.
What is secreted from the endocervical glands?
Varies from thin and watery in the proliferative phase (allowing the passage of sperm) to thick and viscous following ovulation (preventing the passage of sperm or microorganisms)
What is a nabothian cyst?
Occurs when there is a blockage of the endocervical glands
What are the four layers of the vagina?
- non-keratinised stratified squamous epithelium
- lamina propria
- fibromuscular layer
- adventitia
What layer of the vagina is thicker during reproductive years and why?
The non-keratinised stratified squamous epithelium
Cells are enlarged due to glycogen accumulation
Describe the lamina propria of the vagina
Connective tissue rich in elastic fibres and thin-walled blood vessels
Describe the fibromuscular layer of the vagina?
Inner circular and outer longitudinal smooth muscle
How is the vaginal lubricates as there are no glands?
Mucous from the cervical glands and fluid from the thin walled blood vessels of the lamina propria
What prevents the growth of pathogenic bacteria in the vagina?
Commensal bacteria metabolise the glycogen to lactic acid which prevents growth of pathogenic bacteria
Describe the skin of the mons pubis?
Contains highly oblique hair follicles (produce coarse, very curly hair characteristic of pubic hair).
What underlies the skin of the mons pubis?
Substantial subcutaenous fat pad, which itself overlies the pubic symphysis
What is the labia majora?
Extension of the mons pubis
What is found on the labia majora?
Apocrine sweat glands, sebaceous glands and small bundles of smooth muscle.
Hair follicles on the outer surface, but not the inner surface.
Describe the labia minora
Skin folds that lack subcutaenous fat and hair follicles, rich in vasculature and sebaceous glands which secrete directly onto the surface of the skin.
What epithelium extends into the opening of the vagina?
Keratinized epithelium to the level of the hymen where it transitions into non-keratinised stratified squamous
Describe the structure of the clitoris
Contains two tubes of erectile vascular tissue (corpus cavernosa) covered by a fibrocollagenous sheath covered by skin with rich innervation and a thin epidermis.
