Female reproductive tract lecture four Flashcards
What are the female reproductive organs?
Ovaries Uterine tubes Uterus Vagina Mammary gland's
Whats the function of the ovaries?
To produce secondary Oocytes and hormones (oestrogen and progesterone)
What is the function of the uterine tubes?
Transport of secondary oocyte to the uterus and is normally the site where fertilisation occurs.
What is the function of the uterus?
Site of implantation of the fertilised ovum, development of the foetus during pregnancy and labour.
What is the function of the vagina?
Receives the penis during sexual intercourse and forms the lower birth canal. + passageway for mensturation
What is the function of the mammary glands?
Synthesise, secrete and eject milk for nourishment of the newborn
Describe the human ovary?
Small paired organs located near the lateral wall of the pelvic cavity. Flattened oval that weighs 5-10g
Describe the structure of the ovary:
Divided into there distinct regions:
1) Outer ovarian cortex
2) Central ovarian medulla
3) Inner hilum.
What is the function of the outer ovarian cortex?
Contains developing follicles
What is the function of the central ovarian medulla?
Consists of ovarian stroma and cells with steroid producing characteristics.
What is the function of the ovarian inner hilum?
Acts as a point of entry for the nerves and blood vessels.
What covers the ovary?
A single layer of cuboidal epithelium called the germinal (surface) epithelium.
The entire ovary is also covered by a dense connective tissue called the tunica albuginea
What holds the ovaries in place?
The ovary is suspended by ligaments in the pelvic girdle.
What are the ligaments of the ovary?
Broad ligament
Ovarian ligament
Suspensory ligament
What is the dual function of the suspensory ligament?
The major blood vessels of the ovary travel within the suspensory ligament.
Why must the ovary be suspended by ligaments?
To keep the ovary in place so that the uterine tubes fimbriae can collect the released follicles.
Describe the uterine tube:
Hollow muscular tube made up of three distinct regions. Measuring 13cm.
What are the regions of the uterine tube:
The infundibulum
The ampulla
The isthmus
What is the function of the uterine tube infundibulum?
- The end closest to the ovary, forms an expanded funnel.
- Numerous projections (fimbriae), that have cilia which beat and sweep the ejected follicle into the uterine tube.
What is the function of the uterine tube ampulla?
The intermediate part of tube with increasing muscular thickness. (a combination of cilia beating and peristaltic contractions to move the follicle)
Fertilisation typically occurs here.
What is the function of the uterine tube isthmus?
Continuous with the intramural portion of the uterus. No real function of note.
Describe the cellular constitution of the uterine tube:
Contains both ciliated and non-ciliated (secretory) simple columnar cells.
Mucosa is surrounded by concentric layers of smooth muscle.
The infundibulum end has more cilia and less smooth muscle, while the opposite end is more SM and less cilia.
How are follicles transported through the uterine tube?
A combination of cilia beating and smooth muscle peristaltic contractions.
What is ovulation?
Ovulation is where follicles are drawn into the uterine tubes by the fimbriae and into the uterus.
What is the time line of follicle movement through the uterine tube?
Total time is 3-4 days from release to reaching the uterus.
If fertilisation is going to occur then the oocyte must meet the spermatozoa within 12-24hrs.
This typically occurs in the ampulla.
Describe the uterus appearance:
Small pear shaped organ that weight 30-40g.
What is the function of the uterus?
Provides mechanical protection, nutritional support and waste removal for the developing embryo and fetus.
The uterus has a muscular wall, what is the function of this?
To contract and eject the foetus during birth.
What is normal uterus orientation called?
Ante flexion (80%) (bends ant at base)
What is abnormal uterus orientation called and whats the implication of this?
Retroflexion.
Pain in menstruation or intercourse. However child birth reverses this.
What holds the uterus in place and why?
Ligaments - to prevent the range of movement of the growing foetus.
What are the uterine ligaments?
Uterosacral ligament - connection to the sacrum
Round ligament
Lateral (or cardinal) ligament. Extends to the lateral wall of the pelvis.
What are the regions of the uterus?
Uterine body
Fundus - top rounding part above tubes.
Isthmus - inferior constriction ending uterine body.
Cervix - extension of the isthmus
What does the cervix form within the vagina?
The cervix extends and rounds out the end of the uterus. This is called the external os.
When does the uterus fully develop?
Under the influence of oestrogen the uterus grows and becomes function at puberty.
Does the uterus maintain its size throughout life.
The muscular walls expand for pregnancy but return to normal size post gestation.
With menopause the uterus shrinks.
Describe the structure of the uterus:
Outer muscular myometrium
Inner glandular endometrium
What is the structure and function of the uterus’ outer muscular myometrium?
Contains smooth muscle in longitudinal, circular and oblique layers to generates the force to push the foetus out and into the vagina.
What is the structure and function of the inner glandular endothelium?
Contains glandular and vascular tissues to support the growing foetus.
Under the influence of oestrogen the endometrium glands, blood vessels change with various phases of the menstrual cycle.
Can the endometrium be divided?
Yes into:
Inner functional zone
Outer basilar zone (next to myometrium)
and
Basilar zone
Where are the uterine glands located in the endothelium?
Mostly in the slightly thicker inner functional zone.
Whats the role of the basilar zone?
attaches the endometrium to the myometrium and contains the terminal branches of the endometrial glands
Describe the vasculature of the uterine wall:
Within the myometrium branches of the uterine artery form arcuate arteries that encircle the endometrium.
Radial arteries branch out delivering blood to the basilar zone and spiral arteries form and deliver blood to the functional zone
Since the function zone is shed away during menstruation, what happens to the spiral arteries?
They become exanguated i.e stopped form bleeding.
Describe the vagina:
Elastic muscular tube ~10cm long
Extending from cervix to the vestibule.
What is the functions of the vagina?
Receives penis
Passageway for fluids of menstruation
Forms the lower portion of the birth canal.
Describe the structure of the vaginal wall:
Contains networks of blood vessels and smooth muscle layers.
Moistened by secretion from the cervical glands.
The vaginal lumen is lined by stratified squamous epithelium that in a relaxed state collapses into folds called rugae.
How does the vagina inhibit sperm motility?
Glycogen from vaginal cells is converted by bacteria int o lactic acid, lowering pH and inhibiting sperm motility.
What is mitosis?
The division of somatic cells whereby the cell produces two identical daughter cells.
What is meiosis?
Two successive phases that produces gametes.
What are the phases of meiosis?
Meiosis One:
- Prophase
- Metaphase
- Telephase
- Anaphase
Meiosis Two: (sister chromatids are exchanged)
- Prophase
- Metaphase
- Telephase
- Anaphase
Whats the role of meiosis in oocyte production?
Results in the production of the first and second polar bodies.
When is mitosis important in fatal development?
Primary germ cells develop around 3 weeks in the yolk sac and migrate to the genital ridge.
By 6 weeks migration is complete and the primordial germ cells form the gonad and undergo mitotic proliferation
