Flashcards in 38 - Female Reproduction II Deck (92):
What are the four main steps of ovulation?
1 - Follicular changes right before ovulation
2 - Follicle ruptures
3 - Secondary oocyte becomes suspending in metaphase II
4 - The oocyte is ovulated and enters the fallopian tube
What are the follicular changes that occur right before ovulation?
- Blood flow to the cortical tissue of the ovary (which covers the follicle) ceases
- Clear pale spots called stigma form, covering the follicle
- Proteases breakdown the cortical tissue
What happens when the follicle ruptures?
The liquor folliculi is also released
How does the oocyte get from the ovary where it is ovulated to the fallopian tube?
The fallopian tubes contain fimbriae or "fringes" at the distal open end which assists in the capture of the oocyte from the ovary
What happens following ovulation in the ovary?
The granulosa and thecal cells are transformed into a temporary endocrine gland
What is the temporary endocrine gland formed by granulosa and thecal cells called?
Corpus luteum or "yellow body" because it looks yellow in fresh specimen
What is the specific endocrine function of the corpus luteum post-ovulation?
Release estrogen and progesterone in order to prepare the lining of the uterus to receive the blastocyst
If implantation does not occur, what happens to the corpus luteum?
The corpus luteum will persist as the "corpus luteum of menstruation" during day 15-28 of the cycle and will continue to release estrogen and progesterone to influence to endometrial lining
What happens to the corpus luteum after day 28?
It will degerate and become the corpus albicans, which is a "tiny white scar" tissue formation in the ovarian cortex
If implantation does occur, what happens to the corpus luteum?
The corpus luteum will persist as the "corpus luteum of pregnancy" and is maintained by hCG
Before sperm is able to fertilize the oocyte, it must penetrate through two layers. What are they?
1 - Corona radiate (granulosa layer)
2 - Zona pellucida (contains glycoproteins)
Which glycoproteins are found in the zona pellucida of an oocyte?
ZP-1, ZP-2, ZP-3
What happens when a sperm penetrates both layers?
It eventually passes into the cytoplasm of the oocyte
What phase is the oocyte suspended in?
The secondary oocyte is suspended in metaphase II
What needs to happen in order for the secondary oocyte to complete meiosis II?
When a sperm passes into the cytoplasm
What does the sperm release to aid in fertilization?
The acrosome (tip of head) releases enzymes that breakdown the first barrier of the oocyte, the corona radiate
What does the sperm do when it reaches the zona pellucida?
Binds to ZP-3, a glycoprotein which serves as the spermatozoa-binding receptor
What does the sperm binding to ZP-3 induce?
More enzymes to be released from the acrosome that help it to perforate the zona pellucida
What happens once one sperm has completely perforated the zona pellucida?
The "zona reaction" occurs, which changes the composition of the zona pellucida to make it impermeable to other sperm
How many sperm can fertilize a single oocyte?
Once the sperm is inside the cytoplasm of the oocyte, what will occur?
Meiosis II (anaphase and telophase)
Once the fertilized oocyte forms a zygote, how many cells is this structute?
Are any two zygotes the same?
What happens to a zygote as it travels through the fallopian tube?
It under goes cleavage - a series of mitosis
How many cells will from during cleavage?
2 cell --> 4 cells --> 8 cells --> Morula (12-16 cells)
What happens to the morula that causes it to form into a blastocyst?
Fluid fro the uterine cavity passes into the morula and causes the cells to rearrange, forming a blastocyst
What happens after the blastocyst enters the uterus?
It implants in the posterior uterine wall
How many days after fertilization does implantation occur?
The fallopian tube has two ends. What are they called?
- The end that is attached to the uterus is called the "attached end"
- The end that is open near the ovary is called the "open end"
What are the "fringe-like structures" of the fallopian tube's open end called?
What is the normal function of fimbria?
Fimbria normally hover over the ovary so when an oocyte is released, the oocyte can easily pass into the lumen of the fallopian tube
When looking at a fallopian tube in cross section, what will the mucosa look like?
What is the mucosa of the fallopian tube made of?
Epithelium and lamina propria (loose connective tissue)
Why is there a "leaf-shaped" structure to the fallopian tube mucosa?
Increase surface area
What other layers are found in the fallopian tube beyond the mucosa?
Muscularis and serosa
What does the muscularis layer of the fallopian tube consist of?
- A thick inner layer of circular (spiral) fibers
- An outer layer of longitudinal fibers
What type of muscle cells are found in the fallopian tube?
- Paristaltic waves produced by the smooth muscle helps to move the oocyte/zygote toward the uterus
Describe the serosa of the fallopian tube
- Single layer of epithelial cells
- Visceral peritoneum (mesothelium and a thin layer of loose connective tissue)
What type of epithelium would you find on the mucosal folds of the fallopian tube?
Simple columnar epithelium
There are two types of cells found in the epithelium of the mucosal folds. What are they?
- Ciliated cells
- Nonciliated peg cells
What is the function of the ciliated epithelial cells of the fallopian tube mucosal folds?
Move the oocyte through the fallopian tube
What is the function of the non-ciliated peg cells of the fallopian tube mucosal folds?
- Secrete glycoproteins
- Supply nutrients to the oocyte/zygote since there is no placenta yet
What is an ectopic tubal pregnancy?
The zygote implants in the fallopian tube
What happens as the zygote grows in an ectopic tubal pregnancy?
The wall of the fallopian tube stretches and eventually ruptures - this causes a hemorrhage
What does "ectopic" mean?
Outside the normal location where the zygot is supposed to implant
What are the three layers of the uterus?
1 - Perimetrium (outer)
2 - Myometrium
3 - Endometrium (inner)
What does the myometrium consist of?
A middle smooth muscle layer
What arteries run through this layer?
The uterine artery gives rise to the arcuate arteries, which will run circumferentially around the uterus
What do we call the branches of the arcuate arteries that radiate toward the surface of the uterus?
What do the radial branches branch off into? What do these branches supply
- Straight arteries: supply basal layer
- Spiral arteries: supply functional layer
What type of epithelium do we find in the innermost endometrial layer of the uterus?
There is also a lamina propria of the endometrium. What is this called?
What does the endometrial stroma consist of?
- Uterine glands
- Dense irregular collagenous tissue
- Blood vessels
What does the tissue of the uterine cervix consist of?
- 85% dense collagenous connective tissue
- Elastic fiber
- Some smooth muscle (not as much as myometrium)
The endometrium and cervix have one type of epithelium, but the vagina has a different type. What are these two types?
Endocervical = simple columnar, mucous-secreting
Vaginal = stratified squamous, nonkeratinized
Describe the glands of the cervix
- Branched pattern
- Lined with mucous-secreting columnar epithelium
What does a normal cervical smear look like?
- Each squamous epithelial cell contains a pyknotic nuclei
- Abundant cytoplasm around nucleus
What does an abnormal cervical smear look like?
- Large nuclei
- Little cytoplasm around nucleus
There are three phases of the menstrual cycle. What are they?
1 - Menstrual phase (day 1-4)
2 - Proliferative phase (day 5-14)
3 - Secretory phase (day 15-28)
What occurs during the menstrual phase?
- Menstrual flow
What occurs during the proliferative phase?
- Follicular maturation in preparation for ovulation
- Estrogen stimulates the proliferation of tissues in the functional layer of the endometrium
What exactly proliferates in the functional layer of the endometrium?
- Building up of the lamina propria
- Uterine glands proliferate
- Spiral arteries proleferate
What occurs during the secretory phase?
(AKA luteal phase, progestational phase)
- Formation of the corpus luteum
- Progesterone stimulates the synthesis and secretion of glycoproteins by uterine glands
Does the basal layer of the endometrium shed?
NO - just the functional layer
What histological features will you see in poly cystic ovary syndrome? (PCOS)
- Tunica albuginea is excessively thick
- Under the tunica albuginea there are many small immature primordial follicles
What is the tunica albuginea again?
A layer of dense irregular collagenous connective tissue that lies immediately deep to the germinal epithelium
What are the consequences of these histological features of PCOS?
- Incomplete follicular development
- Infrequent or lack of ovulation
How do the cysts form in PCOS?
The abnormally thick tunica albuginea does not let oocytes in the follicles be released during ovulation, so over time, the follicles accumulate and the antrum becomes enlarged, forming the follicular cyst
Will patients with PCOS be fertile?
No, the lack of an ovulatory menstrual cycle results in infertility
Will the corpus luteum form in patients with PCOS?
No, since oocytes are not ovulating
Will there be normal levels of estrogen and progesterone present?
There will be an imbalance in the estrogen/progesterone ratio...
- Estrogen will be produced
- Progesterone will not be produced
What do granulosa cells produce?
Androgens, which are converted to estrogen
How is the menstrual cycle changed in PCOS due to the levels of estrogen and progesterone present?
Estrogen will stimulate the uterine lining, but since there is no progesterone present, the lining will not develop normally
Infrequent menstrual bleeding will be seen in patients with PCOS
What do FSH and LH control?
The growth of follicles and the release of eggs
What happens during the proliferative phase?
- Functional layer of the endometrium proliferates
- Formation of follicle, which releases estrogen
- This stimulates formation of connective tissue, blood vessels and glands
What happens during the secretory phase?
Begins around day 15
- This corresponds to the time when the corpus luteum forms
- Progesterone, produced by the corpus luteum, stimulates the glands in the endometrium to release glycoproteins
- These glycoproteins will nourish the implanting blastocyst if implantation occurs
What happens during the menstrual phase?
- If the ovulated oocyte is not fertilized and implantation does not occur, the corpus luteum stops functioning at about day 14
- Progesterone and estrogen levels drop
- The functional layer of the endometrium sheds
What histological features will we see during the menstrual phase?
- Smooth muscle in the wall of spiral arteries will undergo spasmodic contraction
- Blood flow to the functional layer ceases
- Ischemia leads to necrosis (tissue degeneration) of the functional layer
- The functional layer is "sloughed off"
- The blood vessels break off
- Bleeding occurs
Describe the postmenopausal endometrium
- Thin, atrophic endometrium
- Consists of only stratum basale
- Sparce, inactive glands will be present
What can happen to the glands of the postmenopausal endometrium?
They can form dilated cystic spaces
Are dilated cystic spaces from the glands in the postmenopausal endometrium normal?
Yes - common and normal
What is uterine leiomyoma?
Benign smooth muscle neoplasm that is found in the myometrium
(neoplasm is a tumor or abnormal growth)
What three regions can a uterine leiomyoma occur?
What is one side effect that can occur if the leiomyoma is in the submucosal layer
- Increase in surface area of the uterine endometrium
- Causes heavy menstrual bleeding
How common is it that a leiomyoma will transform into a malignant leiomyosarcoma?
Only about 1% of leiomyomas will transform into a malignant leiomyosarcoma
What type of epithelium is found in the vagina?
Stratified squamous nonkeratinized epithelium
What layers will you find in the vagina wall?
- Lamina propria
What is important to note about the lamina propria of the vagina?
It has elastic fibers
Will there be any glands present in the vaginal wall?
Describe a non-pregnant mammary gland
- Branching duct system of a lobule
- Dense fibrous interlobular tissue
Describe a mammary gland during pregnancy
- The terminal duct epithelium proliferates to form secretory acini
- Separate lobules will be present
- Septa will separate these lobules