Topic 17 -Female Reproductive system

Question 1

gonads=ovaries

located?

Answer 1

located in pelvic cavity on lateral sides of uterus

Question 2

histology of ovaries

4 layers

Answer 2

a) ovarian mesothelium - surface epithelium
b) tunica albuginea - CT
c) ovarian cortex - contains ovarian follicles + CT follicles = layers of cells surrounding immature egg (support + protect)
d) ovarian medulla - blood + lymph vessels, nerves, CT

Question 3

how are the ovaries held in place

Answer 3

a) ovarian ligament - to uterus
b) suspensory ligament - to pelvic wall
c) mesovarium - superior membrane

NOTE: suspensory ligament + mesovarium = parts of broad ligament = parietal peritoneum

Question 4

3 sections of the Uterine (Fallopian) Tubes

Answer 4

a) infundibulum -suspended over ovary
- has finger-like projections= fimbriae
b) ampulla = middle - fertilization occurs here
c) isthmus - connects to uterus

Question 5

histology of Fallopian tubes

Answer 5

a) mucosa - simple columnar epithelium with cilia or microvilli
- moves oocyte or cell mass along tube
- secretes nutrient fluid
b) muscularis externa - smooth muscle - helps movement
c) serosa - visceral peritoneum

Question 6

Uterus 3 parts

Answer 6

a) fundus - above level of uterine tubes
b) body - main portion
- space within = uterine cavity
c) cervix - inferior, narrow portion - opens into vagina

Question 7

supportive membranes (attach uterus to abdominal wall)

Answer 7

a) broad ligaments - peritoneum
b) round ligaments - fibrous CT - attach uterus to anterior body wall
c) uterosacral ligaments
- peritoneum - attach to sacrum

Question 8

histology of uterus

Answer 8

a) perimetrium - outer layer
- visceral peritoneum
b) myometrium - 3 layers of smooth muscle (muscularis externa)
c) endometrium - mucous membrane
- contains endometrial glands – secrete a nutritive fluid

Question 9

2 layers of the endometrium

Answer 9

i) stratum functionalis - faces uterine cavity
- shed monthly (menstruation)
ii) stratum basalis
- permanent
- undergoes mitosis to replace functionalis

Question 10

Vagina

Answer 10

birth canal, passageway for sperm + menstrual flow

Question 11

Vagina histology

Answer 11

a) mucosa - stratified squamous epithelium - rugae
b) muscularis externa
- 2 layers of smooth muscle
c) adventitia - fibroelastic CT - no serosa

Question 12

Female Oogenesis

Answer 12

Oogonia (2n) (mitosis) -> many oogonia (differentiate) -> 1⁰ oocyte (2n) (meiosis 1) -> 1st polar body (n) AND 2⁰ oocyte (n) (ovulated) -> if fertilized, meiosis 2 gives 1 ovum (n) and 2nd polar body (n)

Question 13

1 1⁰ oocyte forms

Answer 13

1 ovum and 2 or 4 polar bodies

Question 14

polar bodies=

Answer 14

discarded nuclear material

Question 15

how many oogonia in a 6 month fetus

Answer 15

5 million

Question 16

how many 1⁰ oocytes (2n) at birth

when do they enter meiosis 1? arrest?

Answer 16

1 million (no oogonia)

enter before birth, arrest in prophase 1

Question 17

at puberty how many oocytes remain?

what stimulates completion of meiosis 1?

Answer 17

400, 000

LH (luteinizing hormone) stimulates completion of meiosis I

Question 18

what does the 2⁰ oocyte (n) do?

Answer 18

begins meiosis II and arrests in metaphase II

• this is ovulated (usually 1/month)
• ~ 500 ovulated from puberty to menopause

Question 19

what are the follicle stages

Answer 19

Primordial follicle 
Primary follicle 
Secondary follicle 
Vesicular follicle 
Corpus luteum 
Corpus albicans

Question 20

Primordial follicle

Answer 20

• in ovary at birth

- 1⁰ oocyte surrounded by a single layer of flat cells

Question 21

Primary follicle

Answer 21

-single layer become cuboidal – cells now called granulosa cells
- granulosa cells proliferate (become stratified) - secrete zona pellucida around oocyte
- theca cells (endocrine) form from surrounding tissue
can reach this stage any time from before birth to menopause

Question 22

Secondary follicle

Answer 22

• at puberty, ovarian cycles begin
• under influence of rising FSH: - granulosa cells proliferate more and start to secrete fluid (accumulates between cells)

Question 23

Vesicular follicle

Answer 23

• on surface of ovary
• fluid filled spaces unite into single large antrum
• granulosa cells that still surround oocyte = corona radiate
  continues secreting estrogen
• estrogen triggers release of luteinizing hormone (LH) causing:
  a) completion of meiosis I
• enters meiosis II and arrests in metaphase II
  b) ovulation – release of 2⁰ oocyte from follicle into peritoneal cavity

Question 24

corpus luteum

Answer 24

• follicle that remains after ovulation
• produces high levels of estrogen and progesterone to support fetal development
• if no pregnancy, degenerates into corpus albicans

Question 25

corpus albicans

Answer 25

scar tissue

no more hormones released

Question 26

Mammary Glands

Answer 26

• 1 per breast
• modified sweat gland
• produces milk
• small compartments = lobules
• contain glands = alveoli
• open via duct at nipple
• surrounded by fat
• attached to deep fascia (epimysium of muscle) by suspensory ligaments