Female Histology Flashcards
Give the sequence of follicular development
Primordial follicle Unilaminar primary follicle Multilamina primary follicle Secondary follicle Ternary follicle Graafian (mature) follicle Corpus luteum Corpus nigricans
What is the conversion which occurs when primordial follicles change?
Squamous granulosa cells become cuboidal
What is a multilaminar primary follicle?
Stratified cuboidal cells, as opposed to simple unilaminar
What do the outer ovarian stromal cells differnentiate into?
Theca folliculi
What do the theca folliculi differntiate into#?
Theca interna
Theca externae
What does the theca interna do?
Secrete oestrogen
What does the theca externae do?
Mostly made up of vascular connective tissue
What is the fluid filled space in the ternary follicle called?
The antrum
What are the layers of granulosa cells around the oocyte called in the ternary follicle
The corona radiata
What is the “peg” the oocyte sits on in the graafian follicle
Cumulus oophorus
Why does ovulation occur?
The tissue around the follicle thins and becomes ischaemic
What does the corpus lutem develop from?
Granulosa and theca interna cells
What are granulosa cells converted into?
Granulosa lutein cells
Secretes progesterone
What are theca interna cells converted into and what do they secrete?
Theca lutein cells
Secretes oestrogen
What happens to the corpus lutem in the absence of fertilisation?
After two weeks it becomes fibrosed, hyalinised into a white connective tissue. Then known as a corpus albicans.
When would a corpus nigricans form?
If process of erythrocyte phagocytosis from centre of corpus luteum is incomplete, the degenerating corpus luteum can form a pigmented corpus nigricans
Name the four sections of the fallopian tube
Fimbria -> Infundibulum -> Ampulla -> Intramural part within uterine wall
Outline the walls of the fallopian tube
Mucosa -> Muscular layer -> Serosal covering
Where is the most folding in fallopian tube?
Ampulla
What type of epithelial cells are there in the fallopian tube?
Columnar
Where are the most numerous cilia cells in the fallopian tube?
Ampulla
What pattern does the number of peg cells in the fallopian tube follow?
More as get towards uterus
How does the structure of the fallopian tube vary along its length?
o In the Ampulla the muscle coat consists of two layers.
o In the Isthmus (shown here) the muscle layer is much thicker and has three layers.
What are the two layers of the uterus called?
Endometrium
Myometrium
What is the endometrium lined by?
Simple columnar epithelium
How many layers of smooth muscle in the myometrium?
Four layers of smooth muscle
What is the blood supply of the endometrium?
Uterine arteries which branch into arcuate arteries
What do the arcuate arteries branch out into? (2)
Straight arteries which ramify in the stratum basalis
Coiled arteries which supply the stratum functionalis
What can the endometrium be divided into?
o Functional (F Stratum Functionalis)
Outer Compact (C)
Deeper Spongy (S)
o Basal (B, Stratum Basalis)
What is the significance of the functional and basal layer?
Functional is shed entirely during menstruation
What are the three phases in the uterine endometrium
o A Proliferative Phase
Under control of Oestrogen
o A Sectretory Phase
Under control of Progesterone
o A Menstrual Phase
Sudden drop in ProgesteroneWhat happens during the proliferative phase?
Stratum functionalis regenerates from cells lining the glands in the stratum basalis
Growth leads to increasing length of endometrial glands and proliferation of stromal cells surrounding these glands.
What happens during the secretory phase?
Increasing levels of progesterone lead to further development of the endometrium. Glands grow more than surrounding lamina propria and become coiled.
Stroma become oedematous and develop into decidual cells. If fertilisation occurs, these assist in formation of placenta and secretion of prolactin.
What are the three types of endometrial glands
Straight, unbranched, tubular glands
What occurs in the menstrual phase?
Absence of fertilisation, progesterone starts to decline. Spasm of spiral arteries due to progesterone decrease causes locally released prostaglandin. This deprives stratum functionalis of nutrients, causing it to become necrotic. Coiled arteries do not go into spasm so the stratum basalis remains.
What is the cervix?
Connects the uterine cavity and the vagina,
Outline the structure of the cervix
External os - Cervical canal - Internal os
What cell type is the cervical canal lined by?
Simple columnar epithelium
EXCEPT for inner aspect of externa Os, epithelium stratified squamous non-keratinised
What kind of glands does cervical canal contain?
Mucous secreting glands
What is the vagina?
Fibromuscular tube
What are the three main layers of the vagina?
Mucosa Submucosa Muscular layer - Smooth muscle - Skeletal muscle
What is the vaginal epithelium?
Stratified squamous non-keratinized
What do epithelial cells in the vagina accumulate? Why?
Glucogen, due to oestrogen, which is a substrate for lactobacilli found within the vagina
What does the vagina conspicuously lack?
Glands
It is lubricated by mucous produced by cervical glands and also by the vestibular glands that open into vestibule.
