Class 12 Female Productive Systems NEET AIIMS
Female Productive Systems
Consists of ovaries, oviducts (fallopian tube), uterus, cervix, vagina, and accessory genitals.Ovaries
Primary female sex organs.
A pair of ovaries are present in the abdominal cavity of a female suspended by a ligament called Mesovarium.
Each ovary is solid & Internally lined by cuboidal germinal epithelium.
There is a pair of ovaries which are attached dorsally in the abdominal cavity with the help of mesovarium. The mesovarium originates from the visceral peritoneum.
The ovary has germinal epithelium inside the mesovarium which is made up of cuboidal germ cells.
The ovary has stroma made up of fibrous connective tissues. The peripheral part of the stroma is condensed which is called the cortex and the inner less dense part is called the medulla.
The cortical part of the ovary has ovarian follicles which are as follows—
(i) Primary follicles
They are formed during the embryonic stage and begin to grow at puberty.
It has an oogonium surrounded by one layer of follicular cells.
(ii) Secondary follicles
It has a primary oocyte surrounded by 2 layers of follicular cells.
(iii) Tertiary follicles
It has primary oocyte surrounded by 3 layers of the follicular cells.
(iv) Mature follicles or Graffian follicles
It is surrounded by a membrana granulosa which consists of two layers viz.—theca externa & theca interna.
It has a fluid-filled cavity, the antrum.
The mature follicle has a secondary oocyte which is attached to the membrana granulosa by a stalk. This stalk is called a germ hill or discus proligerus or cumulus oophorus
The Graffian follicle gradually migrates to the periphery and gets protruded.
The mature follicle bursts at the surface to release the secondary oocyte outside. It is called ovulation.
(v) Atretic follicle
Sometimes, the Graffian follicle fails to ovulate and degenerates gradually. The degenerating Graffian follicle is called the atretic follicle and the process is called atresia.
It is due to a deficiency of vitamin E and hormonal imbalance.
(vi) Corpus Luteum
The follicular cells of the burst follicles reorganize under the control of LH to form corpus luteum.
It has yellow coloured luteal cells containing lutein yellow pigments.
This structure performs an endocrine function and secretes progesterone hormone.
There is a blood clot in the centre of the corpus luteum which is called a corpus haemorhagicum.
(vii) Corpus Albicans
If there is no fertilization, the corpus luteum begins to degenerate. The degenerating corpus luteum is called corpus Albicans.
It is colourless and non-functional.
It’s 3 cm 5 cm 2 cm in dimensions.
The wall of the uterus is composed of outermost layer known as perimetrium and middle wall composed of smooth muscle fibres called the myometrium. The lumen in the uterus is lined by a mucous membrane called the endometrium.
It is made up of three parts –
1. Fundus: upper dome-shaped part, above the opening of the fallopian tube.
2. The body: middle and main part, the wall is formed of outer – Perimetrium, middle – myometrium, muscular, inner Endometrium, vascular.
3. Cervix – Lined by non – keratinised stratified squamous epithelium.
The virgin female vaginal orifice is close to a membranous diaphragm called Hymen.
Also known as oviducts, it has ciliated epithelium.
They extend from ovaries to the uterus.
There is a pair of oviducts which originate from the Mullerian duct.
The anterior end of the oviduct is modified to form ciliated fimbriated or funnel. Its mouth is funnel-shaped which is called ostium. The ovum enters into the oviduct through the oviducal funnel.
1. Ampulla: it opens towards ovary by a fimbriated aperture called Ostium.
2. Isthmus: middle part.
3. Uterine part: Inner part which opens into the uterus.
It is involved in the conduction of ovum or zygote toward the uterus.
Fertilisation occurs inside the Fallopian tube.
Uterus opens into an elastic muscular tube called the vagina.
The vagina is lined by a stratified squamous epithelium without any glands.
During reproductive life, the vagina contains Lactobacillus acidophilus, which keeps the vaginal pH between 4.9 and 3.5 by producing lactic acid from glycogen.
Vagina receives semen from the male during mating. During childbirth, it conveys the child outside.
Vestibule contains openings of vagina and urethra
Numerous minute paraurethral glands, or glands of skene, homologous to the prostate of males, are present around the urethral orifice.
On either side of vaginal orifice is a greater vestibular gland or Bartholin’s gland.
Bartholin’s gland occurs in female mammals and helps in vestibular lubrication.
Bartholin’s gland of female corresponds to the bulbourethral gland (Cowper’s gland) of the male.
The vestibule opens to the outside through vulva or urinogenital opening guarded by two labia majora.
The scrotal sacs of a male mammal are homologous to labia majora of female.
The clitoris is a small organ consisting of erectile tissue and is homologous to the penis of the male.
Types of Uterus
In different mammals, the uteri are of 4 types—
When both the uteri are completely separate, open separately into the uteri.
When anterior 1/3 part of uteri are separate and posterior 2/3 part is fused.
When anterior 2/3 part of the uteri is separate and the 1/3 posterior part is fused.
When both the uteri fuse to form one structure. The uterus opens into the vagina through the neck part
(C) Middle piece
In the middle piece, the axial filament is surrounded by a sheath called manchette. The manchette is made up of nebenkern (fused mitochondria) and a little condensed cytoplasm.
In the sperm of some species, the posterior end of the middle piece may have a ring centriole. The role is not clear.
In the tail, the axial filament is covered by a sheath which is made up of 9 (singlet) fibres. This sheath is absent around the terminal end of the tail.
Most of the sperm are mono-flagellated.
Formation of ova.
– Both mitosis and meiosis take place during oogenesis, three-phase – (i) Multiplication (ii) Growth (iii) Maturation phase
Ova are produced by the division in germinal Epithelium of ovary.
It occurs after the sperm has penetrated the ovum.
Ist polar bodies are produced at the secondary oocyte stage produced by R.D.
25 primary oocyte = 25 egg.
25 secondary oocyte = 25 eggs.
The growth phase of oogenesis is very long –
Ex. Drosophila, 3 days, Henn = 6 – 14 days, Frog, 3 yr. Human female = 12 – 13 yrs.
Size of human egg = .1 mm in diameter.
Ovum is eccentric in position so human egg has polarity.
Animal pole = side towards Nucleus.
Vegetal pole = side away from Nucleus.