Female Reproductive System Flashcards
Parts of the Female Reproductive System
Ovary Uterine tube or oviduct Uterus cervix Vagina Vestibule Vulva
The Ovary
Two ovaries, situated in the dorsal abdominal cavity.
Attached to the abdominal wall by a fold of peritoneum called mesovarium. Within this is a small opening allowing ova to leave the ovary.
Narrows into a ligament called ovarian ligament, then envelopes the ovary forming a bursa. (fluid filled sac).
The structure of the ovary is raspberry- like in appearance.
Made up of connective tissue with ovarian follicles throughout.
The ovary also produces oestrogen.
The Uterine Tube
AKA oviduct or Fallopian tube.
Functions:
- To collect ova as they are released from the Graafian follicles.
- To convey the ova from the ovaries to the uterine horns.
- To provide the correct environment for the survival of both ova and sperm.
Each uterine tube is narrow convoluted structure laying close to the ovary.
The opened end is funnel shaped and known as the infundibulum.
The ova pass down the lumen of the tube, which is lined with ciliated columnar epithelium.
The uterine tube is suspended and attached within the abdomen by a series of ligaments.
The Uterus
Y shaped structure
Lies in the middle of the dorsal abdomen.
During pregnancy the embryo pulls the uterus ventrally.
Functions:
- To provide the correct environment for the survival of the embryos.
- To provide the means whereby the developing embryos can receive nutrients from the dam.
The wall of the uterus has 3 layers
- Endometrium- thickens during pregnancy to provide nutrition for the embryo.
- Myometrium- Layers of smooth muscle which produces strong contractions during pregnancy.
- Mesometrium- Double layer of peritoneum that suspends the uterus from the dorsal body wall in conjunction with ligament attachment.
The Cervix
Short thick walled muscular sphincter that connects the uterine body with the vagina.
Running through the centre is a narrow cervical canal, normally tightly closed and relaxes only to allow the passage of sperm and foetuses.
In non-pregnant animals, the cervix lies in the pelvic cavity.
Blood supply to the reproductive tract.
Ovarian Artery- supplies the ovary, uterine tube and horn.
Uterine Artery - connects with the ovarian artery, supplies the caudal part of the tract and it can seen as a relatively large artery running on either side of the cervix.
The vagina/ Vestibule
These form a channel leading to the external opening of the reproductive tract (vulva)
The vagina leads from the cervix to the external urethral orifice.
The vestibule leads from the external urethral orifice to the vulva and is shared by both the urinary and reproductive tract.
The lumen is lined by stratified squamous epithelium.
The lining epithelium is folded longitudinally to allow width ways expansion during parturition and is surrounded by layers of smooth muscle.
Oestrous Cycle
The rhythmic cycle of events that occurs in sexually mature non- pregnant female mammals.
Function:
- To produce ova ready for fertilisation
- To produce female reproductive tract to receive fertilised ova.
To achieve the aim of fertile mating, the timing of all the interrelated components must coincide.
Each cycle is divided into phases:
- Proestrus- under the influence of Oestrogen.
- Oestrus- Female will allow herself to be mated.
- Metoestrus- under the influence of progesterone.
- Anoestrus- Between cycles, littler or no ovarian activity.
Copulation
Another term for sexual reproduction.
The act in which the male reproductive organ is inserted in the female reproductive tract.
Fertilisation
After mating, sperm male travel up female tract.
Fertilisation takes place within upper part of uterine tube.
Sperm may live as long as 7 days within the tract.
During this period, the outer acrosome of the sperm releases enzymes.
Each ovum is penetrated by one sperm, results in fertilisation reaction.
Cell division begins within a few hours of fertilisation.
Implantation
Blastocysts arrange themselves at equal distances along the horns.
Attach to wall of horns by invading and partly destroying the hypertrophied (swollen) endometrium.
They are then securely implanted.
Occurs between 14-20 days before ovulation in bitch.
Occurs between 11-16 days in queen.
Gestation
Is the carrying of an embryo or foetus inside a female viviparous animal.
Gestation period is the length of time foetus is carried.
Parturition
The process of delivering the young.
Different species give different signs of parturition and the length of time varies.
Hormones Involved
Oestrogen- produced by ovaries.
Follicle Stimulating Hormone- secreted by the pituitary gland.
Luteinising Hormone- secreted by the pituitary gland
Oxytocin- Produces contractions in the uterus.
Progesterone- released by the corpus luteum
