Histology* Flashcards
Ovary: Hilum? Cortex? Medulla? superficial?
hilum - where the blood supply enters - helicon arteries enter from the broad ligament
cortex - contains follicles
medulla - high vascular, connective tissue, nerves, lymphatics
superficial fibrous cortex covered by epithelium
list the layers of the ovary from the top to deep
simple cuboidal epithelium
dense connective tissue: tunica albuginea
connective tissue with stromal cells and muscle fibres
ovarian follicles present at various stages of development
when do germ cells from the yolk sac invade the ovaries and proliferate by mitosis to form oogonia
around week 6
what happens to those germ cells
undergo development and division to via meiosis to form mature oocytes also known as ova
what is oogenesis and what is fulliculogenesis
O - development of oocytes the female germ cells from oogonia
F - growth of follicles which consist of the oocyte and any associated support cells
6 weeks - number and name of cells 7 months birth puberty menopause
1700 germ cells 5 million oogonia 1 mill primary oocytes 500000 all types of follicles few
how does loss of oogonia and oocytes occur
apoptotic process call atresia - cell reabsorbed after death
when does meiosis halt
when does it recontinue
prophase 1
if the oocyte undergoes further development then meiosis will restart otherwise it will remain in this state for several decades
what kind of cell surrounds the primary oocyte
pregranulosa cells without which it would die
squamous cells but when the follicle grows they become cuboidal
what are the 2 changes that happen to cells around the primary oocyte after development
stroll cells are associated with the outside and go on to become the theca
zona pellucid forms between the oocyte and the granulosa cells
with further development which layer proliferates
granular layer
what happens to the stroll cells
inner layers - theca interna - secrete oestrogen precursors
outer layer will remain fibroblast like and form theca external
what releases oestrogen precursors and what happens to them then
theca interna
converted to oestrogen by the granulosa cells
describe the layers of the late primary follicle
what begins to happen in one of the layers
theca externa theca interna basal lamina granulosa zona pellucida
the granulosa cells begin to split
what is the space within the follicle called
antrum
fills with follicular fluid
oocyte still remains surrounded by a granular cells
when the oocyte detaches from the wall what are the granulosa cells surrounding it called
cumulus cells/corona radiata
what are the largest follicles called and how wide can they be
graafian follicles
20mm in dm
what happens in an oocyte in the largest graafian follicle one day before occupation
meiosis 1 but instead of 2 cells it will produce one cell called the secondary oocyte
what happens to other polar body that is formed
carried away to degenerate
what does the secondary oocyte trigger
where does that stop
second phase of meiosis
metaphase 2
when is meiosis completed
after it has been released (ovulation) and fertilised by a sperm will it become a fully mature oocyte
after ovulation what does the follicle transform into
corpus luteum
what do the theca and granulosa cells then secrete
oestrogen and progesterone which help prepare the uterus for implantation
if no implantation occurs what happens to the CL
becomes white coloured connective tissue called corpus albicans
what happens if implantation occurs
placenta secretes HCG which prevents degeneration of the CL
where of the funnel shaped infindibulum move
moves so its opening is adjacent to the site where the follicle ruptures
how does the ovum move down the tube
propelled by gentle peristalsis and currents created by ciliated epithelium
what do secretory cells in the epithelium secrete
nutrients
where does fertilisation usually occur
ampulla and the fertilised ovum is then transported tot he uterus for implantation
fallopian tube labelled from the end to the middle
fimbria infundibulum ampulla isthmus interstitial part
what does the ampulla look like
mucosa is folded and lined by simple columns epithelium with ciliated cells and secretory cells. surrounded by 2 layers smooth muscle
what does the isthmus look like
epithelium mostly secretory with few ciliated cells
3 layers of smooth muscle
what is the uterine wall made up of
inner secretory mucosa called what
then middle
outer layer
endometrium - shed during periods - made up of tubular secretory glands embedded in CT stroma
coat of 3 layers of SM combined with collaged and elastin called the myometrium
outer visceral covering of loose connective tissue covered by mesothelium - perimetrium
what is the inner layer divided into
stratum functionalis - undergoes monthly growth, degeneration and loss
stratum basal is - reserve tissue that regenerates SF (part of endometrium and myometrium)
during the proliferative phase what happens
glands, stroma and vasculature grow - increases the thickness of the endometrium
what happens during the secretory phase
glands become coiled with a corkscrew appearance and secrete glycogen
what happens during the menstrual phase
arterioles in the functionalism undergo constriction - ischeamia - tissue breakdown and tissue sloughing
what is the cervix
short cylinder with a small lumen that projects into the upper vagina
what is the histology of the cervix
mostly fibrous connective tissue covered by stratified squamous epithelium on its vaginal surface by transitioning to mucous secreting epithelium simple columnar epithelium - transition zone - frequent place for cancer
where are the mucous secreting epithelium of the canal
deep furrowed - forms endocervical glands which secrete thin stuff first to allow sperm through then thick stuff to prevent the passage of sperm and micro organisms after ovulation
list the 4 layers of vagina
non keratinised stratified squamous eputhlium
lamina propria
fibromuscular layer
adventitia
are there glands in the walls of the vagina
no - lubricated y mucous form cervical glands and fluid from the thin walled vessels of the lamina propria
how is the growth of pathogenic bacteria inhibited
commensal bacteria metabolise the glycogen to lactic acid which inhibit the growth
what is the external gentile outer layer called and what does it consist of
labia majora
extension of mons pubis, similar structure and rich in apocrine swear glands and sebeceous glands and with small bundles of smooth muscle
hair follicles on the outside
labia minora
lacks
has more of
thin skin that lack subcut fat and hair follicles
rich in vasculature and sebaceous glands
where is the transition in cells in the labia minora
hymen - goes from keratinised from opening of vagina to hymen then its non keratinised stratified squamous epithelium
what does the clitoris contain
two tubes of erectile vascular tissue covered by fibrocollageneous sheath covered by skin with rich innervation and a thin epidermis
