Female Tract, Oogenesis and Endocrine Control Flashcards
What is oogenesis
What process by which oogonia develop and from mature oocytes.`
Primordial germ cells in the ____ ___, migrate to the ____ ____ at about _ weeks gestation. These oogonia start to divide (mitosis) and then get to _____ of ____ 1
Primordial germ cells in the yolk sac, which migrate to the gonadal ridge at about 6 weeks gestation. These oogonia start to divide (mitosis) and then get to prophase of meiosis 1
Formation of oocytes before puberty and meiosis
Meiosis begins in the developing ovary following mitosis of oogonia. This arrests at the end of prophase 1 (Just prior to metaphase). Now called (primary) oocytes. (primordial follicles)
Overview of the follicular phase, and how many follicles of each type develop
NB __ days from activation to antrum formation
Primordial: present 12-50 years after the arrested state. Millions
Primary: 30-50 advance, 2-3 months gestation
Secondary: 15-20, 2 weeks rapid growth. Loss of these by atresia
Tertiary/Graafian: 1-2 of them
85
Primordial follicles: anatomy
Primary oocytes, single layer of flattened granulosa cells. Then outer stromal
Primary follicle
Primary oocyte, cuboidal granulosa cells around
Secondary follicle
Granulosa cells do what under the influence of what?
Theca cells?
Primary oocyte surrounded by multilayered cuboidal granulosa cells. These express FSH receptors
Granulosa cells, under FSH influence produce: oestrogen, inhibin, AMH
Theca cells express LH receptors, to produce androgens
What is the steroid pathway and why is it important?
Progesterones make androgens which make oestrogen
Need androgens to make oestrogen
So androgens made by theca cells goes into granulosa cells to make oestrogen
SMALL tertiary follicle
Characterised by the presence of an antrum, containing follicular fluid
Also theca interna and externa
What is the zona pellucida and what are its constituents. What is it for?
Protein membrane surrounding oocyte madecof ZP-1 2 and 3
ZP-1 introduced when it is primordial. ZP-2 and 3 during activation
Filtering normal sperm and polyspermia
Tertiary/ Graafian follicle
Large antrum, with area of granulosa cells where oocyte is budding into the antrum called cumulus oophorus. Also a secondary oocyte
What part of the follicular phase in gonadotrophin independent and role of AMH
Up to where secondary follicles are formed, independent of FSH and LH. Only tertiarly follicles gonadotrophin dependent
AMH stops primordial to primary follicle formation
AMH is produced by granulosa cells, so level of AMH is an average way to know follicular reserve. If it i high, likely more follicles there
How is the corpus luteum formed?
Following ovulation, the leftover granulosa and theca cells from the mature follicle are /lutenised’ and form the corpus luteum. Produces progesterone
Key features of the menstrual cycle (follicular and luteal phases; proliferative and secretory phases too) DRAW OUT
___and ___ are produced, ___ rises.
This causes increase in ____ production. Negative feedback from _____ stops ___ and ___ release.
Day __, sustained, and very high ___ causes positive feedback, causing an __ surge. This causes ovulation (12-13)
______ production from corpus luteum in the ___ phase
Start of the ovarian cycle is menstruation.
FSH and LH are produced, FSH rises.
This causes increase in oestrogen production. Negative feedback from oestrogen stops FSH and LH release.
Day 10, sustained, and very high oestrogen causes positive feedback, causing an LH surge. This causes ovulation (12-13)
Progesterone production from corpus luteum in the luteal phase
Role of of inhibin and when it surges.
At about ovulation, and then in the luteal phase, produced by granulosa cells. Stops FSH from being released
What does progesterone do to body temp?
Increases basal body temperature
What can be said about menstrual cycle length (400 cycles)?
Differences between follicular and luteal phase
Varies a lot. Decreases with age and varies most when young and when older. Stale at mid point.
Follicular phase is more longer and more variable in length (17.6 +-4) than the more constant luteal phase (12.7 +-1.7)
Fallopian tube divisions; structure; epithelium
Infundibulum with fimbriae; Ampulla (wide); Isthmus
Epithelial layer, muscular (IC,OL), serosal
Epithelium: ciliated and secretory. Respond to steroids
Effect of E2 and P4 on FT’s
E2: Promote cilia movement, secretion and increase of muscular
P4: Decrease in muscular activity, decrease in cilia (increased frequency) and decreased secretions
The uterus is about __cm long.
During pregnancy, a change in physiology accommodates _L of _____, _____ and _____.
The uterus is about 7.5cm long.
During pregnancy, a change in physiology accomodates 5L of amniotic fluid, baby and placenta.
Uterine layers. Functions
NB decidua endometrium is the tissue lost during menstruation. Functional layer
Perimetrium(serosa)
Myometrium: Bulk of tissue. Unchanged during menstrual cycle. Forceful expulsion of foetus in parturition
Endometrium: Two layers. Basal and fuctional (glands and simple columnar epi.). Functional layer is the part that grows due to hormones
How the stratum functionalis changes in reference to the menstrual cycle
____ (__-__ days) the stratum is falling. __ is rising, oestrogen not rising much.
Proliferative phase. (days -) ____are high, eventually causes LH surge. Oestrogen causes proliferation. Glands are ____.
____: Day 14 on. Progesterone and___ high (secreted by _____ ___). Lining maintained. Glands ____
Menses (5-7 days) the stratum is falling. FSH is rising, oestrogen not rising much.
Proliferative phase. (days 7-14) Oestrogens are high, eventually causes LH surge. Oestrogen causes proliferation. Glands are circular.
Secretory: Day 14 on. Progesterone and inhibin high (secreted by corpus luteum). Lining maintained. Gland torturous
What is the decidual reaction
In preparation for implantation, the endometrial stroma becomes oedamatous, fibroblasts enlarge and secrete glycogen. Occurs every menstrual cycle
Uterine blood supply
theory on vessel coiling
Uterine artery to arcuate arteries. These to radial arteries then spiral arteries and basal arteries (in basal layer)
These spiral arteries, the terminal ends are lost with the functional layer. Thought that they spasm, closing themselves off. They grow during proliferative phase
Vessel coiling maybe due to fact that when uterus stretches, to accommodate tissue expansion
NB Lab.
Endometrial dates
Gland mitoses: Tortuorsity: Basal vacuolation: secretion: stromal oedema: decidual reaction: stromal mitoses: Leuckocyte infiltration:
Gland mitoses: proliferative
Tortuorsity: secretory
Basal vacuolation: Post ovulation, right after glands have secreted things.
secretion: secretory
stromal oedema: Follows oestrogen, so prolif. and secretory
decidual reaction: before menses
stromal mitoses: proliferative phase, some secretory
Leuckocyte infiltration: around menses
Role of estrogen and the uterus
Cell proliferation (epi. and stromal) Stromal oedema Serous secretions myometrial activity. synthesis of intracellular P4 receptors
Role of progesterone on uterus
Thick glandular secretions
stromal proliferation
decidual reaction
inhibits myometrial activity
Endometriosis
Endometrium outside the uterus. Causes thought to eb retrograde menarche, lymphatic movement or stem cells outside.
Associated w infertility and chronic pelvic pain
Two parts of the cevix. There is a junctional zone in some people (where HPV and cervical cancers are located)
Endocervix: Columnar epi. , glands and crypts, fibrous stroma, few SM cells
Ectocervix: stratified squamous epi.
How does cervical mucous change throughout a menstrual cycle
How do the hormone profiles coincide
Viscosity: Starts high, and dips at mid cycle, then goes to quite high again
Volume starts lower and peaks mid cycle, then goes back donw
Threadability: Peaks mid cycle with the clear watery mucous
Estrogen causes watery, threadable(spinnbarkeit) mucous at mid cycle. Passage for sperm to travel through
Progesterone (second half) causes mucous to be cross linked, no sperm passage
