Female Reproductive Tract Anatomy

Question 1

What are the components of the female reproductive tract?

Answer 1

• Paired gonads (ovaries) - Paired oviducts (=/~ fallopian tubes) - Uterus: uterine horns, uterine body, cervix - Vagina (repro) - Vestibule (repro + urinary) - Vulva

Question 2

What are the 2 functions of the ovaries?

Answer 2

1. Produce gametes 2. Produce hormones

Question 3

What is meant by ‘monovular’?

Answer 3

Ovulates a single oocyte (derived from a single egg/ovum) –>Polyovular - ovulates >1 oocyte

Question 4

Outline the structure of the ovaries

Answer 4

• Outer cortex (follicles and corpora lutea) - Central medulla (blood vessels, lymphatics, nerves, CT)

Question 5

What consists of the ovarian parenchyma?

Answer 5

1. Follicles 2. Interstitial cell types

Question 6

Outline the continuum of follicular development.

Answer 6

1. Primordial follicles 2. Primary follicle 3. Secondary follicle 4. Tertiary follicle –> Tertiary (Graafian) follicle –> Rupture of follicle –> C. luteum –> C. albicans

Question 7

What is indicative of a primary follicle (in outer cortex of ovary)?

Answer 7

• Onset of follicular maturation
• Flattened cells become cuboidal epithelium (granulosa cells)
• Zona pellucida (ZP) becomes visible = glycoprotein coat surrounding oocyte designed to prevent polyspermy

Question 8

What is indicative of a secondary follice (found in cortex of ovary)

Answer 8

• Follicles with stratified epithelium, enclosing oocytes with a distinct Zona Pellucia
• Small fluid-filled spaces become visible btw granulosa cells (cuboidal epithelium) –> Spaces fuse to form antrum
• Thecal cells (theca=cup) = epithelial cells outside. Form a wall around follicles start to produce oestrogens

Question 9

What are some features of tertiary follicles (in cortex of ovary)?

Answer 9

• Follicular epithelium produces fluid
• Forms ANTRUM

Tertiary (Graafian) Follicle

• Increases further in size
• Oocyte floats in antrum
• ~12 hrs before ovulation –> stigma forms –> follicle ruptures (stigma and oocyte released)

Question 10

Key changes following a follicle rupture (outer cortex of ovary)?

Answer 10

• Empty follicle filled with blood
• Wall collapses & folds
• Cell luteinization & proliferation occurs
  (Corpus luteum forms through vascularisation, follicular cell hypertrophy, lipid accumulation, endocrine organ - progesterone)
• Corpus albicans
  (scar from old CL, “white body”)

Question 11

What are the 3 tunics of the female genital tract?

Answer 11

1. Mucosal tunic (inner) - forms longitudinal folds in oviduct & non-gravid uterus
2. Muscular tunic (middle tunic) - 2 muscle layers:
   - inner circular and
   - outer longitudinal layer
   (separated by highly vascular layer)
3. Serosal (adventitial) tunic - composed of peritoneum, covering surface of oviduct, uterus and part of vagina

Question 12

What is the structure and function of the Infundibulum?

Answer 12

• Thin-walled funnel, cranial extremity oviduct
• Free-edge of funnel (fibriae) come into contact with ovary
• Captures Ovum

Question 13

What is the structure and function of the Oviduct? (including layers)

Answer 13

• Narrow, flexuous tube
• Fertilisation occurs in oviduct
• Joins apex of horn of uterus at uterotubal junction

3 layers:

• Serosa: lines the surface
• Muscularis: responsible for movement of sperma & ova
• Mucosa: folded, dividing the lumen into complex shape
• Mucosal folds decrease in complexity distal to the ovary

Question 14

What are the components of the uterus?

Answer 14

• Uterine horns
• Body
• Cervix
• Endometrium (mucosal layer): uterine glands
• -> ruminants have caruncles for embryo attachment
• Myometrium (fibromuscular layer)

Question 15

What makes up the cervix?

Answer 15

• Mucous secreting cells - produce material that hardens/seals off uterus
• Cervical wall - very muscular & capable of contraction

Question 16

Where is the vagina located and what is it bound to?

Answer 16

Section of reproductive tract from the cervix to the entrance of the urethra (urethral orifice)

The fornix is a ringlike space (intrusion of cervix into vagina)

• Dorsally bound by CT to rectum
• Ventrally bound to urethra
• Long thin-walled and distensible in length and width

Question 17

What is the location of the vestibule?

Answer 17

Extends from the urethral orifice to the external vulva

• May be a transverse mucosal ridge (hymen) at junction btw vagina and vestibule
• Vestibule walls are less elastic than vagina and come together at rest
• Mucosal layer contains lymphatic nodules

Question 18

What does the vulva consist of?

Answer 18

• 2 laterally positioned labia (fatty tissue, highly vascular)
• Bordering a slit-like opening: vulval cleft

Question 19

What is the purpose of paired broad ligaments in the peritoneum?

Answer 19

Paired broad ligaments suspend the genital system from dorsolateral wall.

Question 20

What is the role of the placenta?

Answer 20

Combination of foetal and maternal tissues for exchange of materials between mother and foetus.

• Provides metabolic requirements of foetus
• Removes waste from foetal circulation
• Prevents mixing of foetal and maternal blood
• Associated with hormone production

Question 21

What is meant by the term “placentation”?

Answer 21

Attachment of the outer-most foetal membrane (chorion) to the endometrium (uterus).

Question 22

What is the role of the umbilical cord?

Answer 22

Umbilical cord connects foetus to chorioallantois

• Aminion covers surface
• Umbilical vessels
• Urachus: link between allantoic cavity and urinary bladder

Question 23

What is the structure of a cotyledonary placenta and what animals may you find this in?

Answer 23

• Found in ruminants
• Uterine caruncles (mother): round elevations on endometrial surface

Question 24

What makes up a placentome?

Answer 24

Caruncle (M) + Cotelydon (F)

Question 25

A zonary placenta would be found in what animals?

Answer 25

- Carnivores - Attachments occur along a central band surrounding the embryo - Maternal epithelial & connective tissue layers are destroyed during implantation

Question 26

What animals would you find have a diffuse placenta?

Answer 26

Sow, horse (mare) - Areolae: shallow, cup-shaped indentations in the chorion. Circular spaces between chorionic surfaces and endometrium. Uterine milk is released. - Occur opposite uterine endometrial glands - Chorionic epithelial cells lining areolae absorb glandular secretions - Surface area of maternal-foetal interface is increased by microcotyledons (F) and crypts (M) associated with villi.

Question 28

What is the structure of the mammary glands?

Answer 28

- Modified & enlarged sweat glands - Develop as mammary *buds* along mammary *ridges i*n embryo. _Consists of:_ Glandular tissue - parenchyma Fatty infiltrates Fibrous tissue framework Multiple mammary glands (or single complex e.g. udder) Each gland has a branching duct system Glandular tissue divided into ***lobules*** by CT Lobules consist of **_alveoli_** (functional unit)

Question 29

What are the functions of the mammary glands?

Answer 29

- Nourish offspring - Deliver maternal antibodies to newborn offspring (in colustrum)

Question 30

Outline the comparative anatomy of mammary glands.

Answer 30

_Cow_ * Location = “Inguinal” (caudal abdomen, cranial pelvis) * Each gland has its own independent duct system, draining to a teat * Each teat has a single opening * Suspensory apparatus * Udder can be very heavy during lactation * Suspensory apparatus supports the udder * Each gland (quarter) is suspended by: Medial lamina (\*\*Most important) Lateral lamina _Small Ruminants_ * Very similar to cow, except: * 2 mammary glands * Accessory teats are common * Milk veins are less prominent _Carnivore_ Number of mammary glands: * Bitch - 4 – 6 pairs of mammary glands (usually 5 pairs) * Queen - 4 pairs of mammary glands Location: * Thoracic, abdominal, inguinal Number of teat ducts: * Bitch - 8 – 20 * Queen - 4 – 7 Glands enlarge during pregnancy & lactation Become swollen & pendulous _Mares_ * 2 mammary glands form the udder (R & L halves) * Each mammary gland drains through 2 teat openings at a single teat * Therefore mare has 4 mammary “quarters” like a cow, but only 2 teats (each with two canals) * Composition similar for cow, but relatively smaller _Pig_ * 7 – 8 pairs of mammary glands along ventral trunk (thoracic – inguinal regions) * Each gland drains into a teat via 2 openings

Question 31

What is the route of milk production in the mammary gland?

Answer 31

Glandular cells --\> drains into intralobular ducts --\> drains into interlobular ducts --\> lactiferous ducts --\> lactiferous sinus (1. Gland sinus 2. teat sinus) --\> papillary duct --\> teat orifice