Histology Flashcards
where is a common site for ovarian cancer
the cuboidal epithelium of the ovary
what is oogenesis
development of oocytes, the female germ cells from the oogonia
what is Folliculogenesis
growth of the follicle, which consists of the oocyte and any support cells
how is an oogonia formed
around week 6 of embryonic development, germ cells from the yolk sac invade the ovaries and proliferate by mitosis»_space; oogonia
how are mature oocytes made
oogonia undergo development and division via meiosis to form oocytes [a.k.a ova]
what is atresia
loss of oogonia and oocytes by apoptosis > cell is reabsorbed following cell death
what are pregranulosa cells
follicle cells
what happens if an oocyte fails to associated with a pregranulosa cells
it will die
what is the histology of pregranulosa cells
begin squamous
if the follicle enters growth phase, they will become cuboidal
what are primary follicles defined by
cuboidal granolas cells
- zona granulosa
what cells go on to form the theca in primary follicles
stromal cells
during follicular development as the oocyte engages, what forms between the oocyte and granulosa cells
layer of special ECM
- zona pellucida
what does the theca interna layer go on to do
secrete oestrogen precursors
what converts the oestrogen precursors into oestrogen
granolas cells
how is a secondary follicle formed
A space, called the antrum, filled with follicular fluid begins to form and enlarge in the granulosa layer
what are Graafian follicles
very largest follicles
what happens 1 day before ovulation
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
what does the secondary oocyte do
begins second phase of meiosis but will stop at metaphase II
when would the secondary oocyte complete meiosis
after it has been released (ovulation) and fertilized by a sperm
what happens to the follicle after ovulation
transforms into the corpus luteum
what does the corpus luteum secretes, through what cells and why is this important
theca and granulosa cells secreting oestrogens and progesterone
helps prepare the uterus for implantation
what happens to the corpus luteum if no implantation occurs
becomes corpus albicans
what happens to the corpus luteum if implantation occurs
the placenta secretes HCG which prevents degeneration of the corpus luteum»_space; maintains progesterone levels,»_space; maintains the pregnancy
what are the parts of the uterine tube
isthmus
ampulla
infundibulum
fimbria
what does the infundibulum of the uterine tube do
moves so that its opening is adjacent to the site where the follicle ruptures
what propels the ovum down the tube
by gentle peristalsis and currents created by the ciliated epithelium
where does fertilisation occurs
in the ampulla
what is the ampulla composed of
the mucosa is folded and lined by simple columnar epithelium with ciliated cells and secretory cells.
This is surrounded by smooth muscle
what are the 3 parts of the uterus wall
endometrium
myometrium
perimetrium
what is the endometrium
inner secretory mucosa which is shed during menstruation
what is the endometrium made up of
tubular secretory glands embedded in a connective tissue stroma
what is the myometrium
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
stratum basalis
what is the role of the stratum functionalis
undergoes month growth, degeneration and loss
what is the role of the stratum basalis
reserve tissue that regenerates the functionalis.
how is the thickness of the endometrium increased during the proliferative phase
the glands, stroma and vasculature grow
what happens during the secretory phase in the uterus
glands become coiled with a corkscrew appearance and secrete glycogen.
what happens during the menstrual phase in the uterus
arterioles in the functionalis undergo constriction, depriving the tissue of blood and causing ischemia, with resultant tissue breakdown, leakage of blood
what is the cervix composed of
fibrous connective tissue covered by stratified squamous epithelium ON ITS VAGINAL SURFACE
BUT
transitioning to mucous secreting simple columnar epithelium
why is it important to know about the transition zone
common site of dysplasia and neoplastic changes leading to cervical cancer
what is the transition zone
area in the cervix where the histology changes from stratified squamous epithelium TO simple columnar epithelium
why is the epithelium of the cervix canal important
mucous secreting endocervical glands
- these secretions vary from thin and water in proliferative phase
- to thick and viscous following ovulation
what are the 4 layers of the vagina wall
- Non-keratinized stratified squamous epithelium.
- Lamina propria
- Fibromuscular layer
- Adventita
why is the Non-keratinized stratified squamous epithelium. thicker during reproductive years
due to glycogen accumulation
why is having glycogen in the vagina important
Commensal bacteria metabolize the glycogen to lactic acid which inhibits the growth of pathogenic bacteria.
how is the vagina lubricated as it has no glands
mucous from the cervical glands and fluid from the thin walled blood vessels of the lamina propria
what is mons pubis
skin containing hair follicles overing subcutaneous fat pad overlying the pubic symphysis
what is labia majora
Extensions of mons pubis, similar structure and rich in apocrine sweat glands and sebaceous glands
what is labia minora
hin skin folds that lack subcutaneous fat and hair follicles, but are rich in vasculature and sebaceous glands that secrete directly onto the surface of the skin
what histology is seen in labia minora and when does it change
Keratinized epithelium extends into the opening of the vagina to the level of the hymen, where there is a transition to non-keratinized stratified squamous epithelium.
what is the clitoris
Contains two tubes of erectile vascular tissue (corpora cavernosa), covered by a fibrocollagenous sheath covered by skin with rich innervation and a thin epidermis.
