Microanatomy of Reproductive System Flashcards
What is the female reproductive system composed of ( Hint: 6 )
1- Ovaries 2- Fallopian tubes 3- Uterus 4- Cervix 5- Vagina 6- Placenta ( when pregnant) 7- mammary glands ( nutrition for newborn )
What are oocytes
female gametes
What is the Function of ovaries
Where oocytes are developed
What is the function of Fallopian tubes
Collects ovulated oocytes and is the site of fertilization
What is the function of the uterus
Site of decidualisation , menstruation , implantation and placenta growth
What is the function of the cervix
Neck of the uterus that provides aa barrier to infections. Dilates and secretes to regulate partition and reproduction
What is the function of the Vagina
Key deposition of sperm and protection of reproductive tract.
What happens during menopause
Reproductive system undergoes attrition , it involutes and stops functioning reproductively.
What encapsulated the ovary
Tunica Albuginea
What lines the ovaries
Single layer of germinal epithelium on the exterior of the tunica Albuginea
What is the ovary composed of and what does each section contain ( not including Tunica albuginea and epithelium )
Cortex: oocyte and follicular development
Medulla : loose CT with BV from hilum and fibroblasts
What is the function of the fibroblasts in Medulla
Sense levels of hormones in the ovary
What are the follicles in the ovary cortex
Structures that contain the oocytes.
What are primordial germ cells
Cells that gave rise to female gametes ( haploids ). When women is pregnant the developing baby will have her own germ cells move to gonads and develop to into oogonia
During the first 3-8 months of gestation what happens to primordial
Primordial germ cells develop into large primary oocytes
How many follicles are produced in utero vs at puberty
4 million but many are lost through atresia that by puberty there’s only 200K left. .
Approximately how many oocytes are ovulated for potential fertilization
450
What is follicular maturation
Changes of oocyte during monthly cycle.
What are the 4 distinguishable follicles during maturation stages in monthly cycle
1- primordial follicles
2- primary follicle
3– Secondary follicles
4– Mature graafian follicles
What follows the antra follicle stage where there is a mature graafian follicle
Oocyte will be ovulated ( leave ovary ) and collected by Fallopian tube
What is the corpus luteum
The Graafian mature follicle without the oocyte ( since it got ovulated )
What is the function of the corpus luteum if there is a pregnancy
Major endocrine regulator during first months of pregnancy until placenta develops and takes over ( 3 months ).
What happens to the corpus luteum if there is no pregnancy
Will regress and the follicular cells will undergo atrophy and become fibrotic. Structure left will be called corpus albican
Why is the corpus luteum yellow
Because there is a lot of progesterone and estrogen being produced
What are primordial follicles
Principle follicles present before birth
Consist of oocyte surrounded by single layer of follicular cells that develop into granulose cells
Explain the process of primordial follicle becoming a primary follicle
Every month 20-40 primordial follicles are stimulated to grow bigger.
Oocyte grows bigger and secrete zona pellucida and granulosa cells turn into cuboidal shape.
What is zona pellucida
a thin glycoprotein coating secreted by the oocyte once it grows and separates the oocyte from the granulose cells
How many graafin follicles are there
Only 1
Explain the process of primary follicle becoming a secondary follicle
Increase of granulosa cell layers and it becomes called zona granulosa with a basement membrane that separates granulosa cells from outer Theca cell layer
What are theca cells and list their functions
Cells that form outside the follicle. Two layers.
- theca interna : produces oestrogen and progesterone
- theca externa
What is follicular antrum and when does it happen
When the secondary follicle matures fluid forms in follicle to nourish granulosa cells
Explain the process of secondary follicle becoming a graafin follicles
Oocyte moves ecentrically.
Follicle grows as antrum enlarges.
Follicle cells form around oocyte . ( corona radiate )
What is the corona radiate
crown of cells surrounding oocytes in graafin follicles
What is the effect of FSH on ovary ( Hint: 4 steps )
1- stimulates follicular development every month
2- stimulates granulosa cells to produce oestrogen and progesterone
3- Increase in oestrogen levels cause increase of LH
4- increase Oestrogen will inhibit more FSH and some follicles will die off
What is the effect of LH on ovary ( explain what happens in detail )
1- Stimulates ovulation and development of corpus luteum
2- increases follicular fluid and pressure , thinning the ovarian cortex surrounding follicle until it ruptures and oocyte is released into Fallopian tube
When is there a surge in LH levels
around day 13 of ovulation cycle
What is the name of the pain caused when follicle ruptures. and what causes it
Mittelschmertz. Caused by release of follicular antrum in pelvic cavity causing irritation
Is the ovary attached to the Fallopian tube
No , finger like extensions from Fallopian tube at ovulation come to lie over the ovary creating a current so when oocyte is released from ovary it can waft the oocyte into Fallopian tube
What is the name of the extensions of fallopian tube that lie over ovaries during ovulation
Fimbriae
What lines the Fallopian tube
simple columnar epithelium with secretory and ciliated cells
What is the Fallopian tube attached to
the uterus
What does the Fallopian tube consist of
1- Infundibulum : mucosa that’s highly folded and a thin muscularis ( where fimbriae are)
2- Ampulla : mucosa is highly folded and a thick muscularis
3- Isthmus : mucosa has less folds and muscularis is at its thickest
What surrounds the Fallopian tube
Smooth muscle layer
Why is the fallopian mucosa highly folded
To increase the surface area of secretory cells which secrete fluid that allows oocyte to float and get nourished
What is the function of ciliated cells in fallopian epithelium
Provide current which moves the oocyte in one direction, towards where the spermatozoa would be swimming up
What is a common cause of infertility
Blockage of Fallopian tubes so oocytes can’t move through
What is the uterus composed of
3 layers
1- Endometrium ( inner )
2- Myometrium ( middle )
3- Perimetrium ( outer )
What is the perimetric composed of
CT
What is the myometrium composed of
Smooth muscle and vasculature
What is the Endometrium composed of
2 components
1- Stratobasalis
2- Stratofunctionalis : lost every month during menstruation and regrows
What nourishes the stratobasalis
nourished by arteries from the myometrium
What important feature is in the stratofunctionalis
Plenty of glands for zygote to be able to implant ( must be glandular tissue )
What is the function of male reproductive system
Formation of spermatozoa , androgen sex hormones ( testosterone ) and facilitation of fertilization of spermatozoa into female
What is the male reproductive system composed of
1- Testis 2- Genital ducts 3- Epididymis 4- Accessory glands 5- Vas deferens 6- Penis
What is the location of the testis
Found in extension of anterior abdominal wall called scrotum
What is the function of testis
Production of spermatozoa and sex hormones
What stimulates the production of testosterone and spermatozoa
The anterior pituitary
FSH: sperm
LH: testosterone
What is the most superficial layer of the testis
A thick CT capsule called tunica albuginea
What is the function of the tunica albuginea in the testis
Gives rise to septa that divides the organs into 250 lobules
What is contained in each testis lobule
seminiferous tubules that connect via rete testis
What is the function of the rete testis
Bring the spermatozoa into efferent ducts which lead to epididymis
What is the function of seminiferous tubules
site of spermatogenesis
What is the epithelial layer of seminiferous tubules composed of
Lining of Leydig cells and Sertoli cells
What is the function of Sertoli cells
Support and nourish developing germ cells
What is the function of Leydig cell
spermatogenic cells that will develop into spermatozoa
List the 4 populations of germ cells
1- Spermatogonia
2- spermatocytes ( primary and secondary )
3- spermatids
4- spermatozoa
What happens when spermatogonia undergo mitosis
Give rise to two types of cells , a primary spermatocyte and spermatogonia cell
What happens once spermatozoa are formed
They are related into lumen of seminiferous tubules which collects into rete testis and then into efferent ducts and then vans deferens
How do Sertoli cells connect to one another
By tight junctions
Where are Sertoli cells
tall cells going from basement membrane to lumen
What is the Epididymis
Highly convoluted duct that is the site of sperm storing and maturation
What lines the Epididymis
Pseudostratified columnar epithelium with microvilli
What are stereocilia
microvilli in Epididymis that absorb fluid that was released by sertoli cells
What is the Vas Deferens
Where the spermatozoa are moved from Epididymis to urethera during ejaculation by muscle contraction
What lines the Vas deferens
columnar epithelium and encapsulated with dense irregular CT
Histologically describe the Vas deferens
Thick walled with 3 muscle layers
What are seminal vesicles
paired glands that produce secretion containing sperm-activating substances
What is the function of the prostate gland
produces thin, milky fluid containing enzymes making ejaculation alkaline enough to counter vaginal acidity
What are Bulbourethral glands
paired glands that secrete small amount of fluid prior to ejaculation to lubricate urethra and neutralize it from urine
Histologically describe the penis
erectile tissue composed of DIRCT and smooth muscle
What are the 3 columns making up the penis
2 corpus cavernosa
1 corpus spongiosum: contains the urethra and carries sperm in ejaculation
What is the location of corpus cavernosa
sits distally to corpus spongiosum separated by septum
