HUMAN REPRODUCTION
THE MALE REPRODUCTIVE SYSTEM.
Located in the pelvis region.
Male reproductive system includes
A pair of testes.
Accessory ducts.
Accessory glands.
External genitalia
Testes:
Located outside the abdominal cavity within a pouch called scrotum.
Scrotum provides low temperature required for spermatogenesis.
Each testis is about 4 to 5 cm length and 2 to 3 cm width.
Each testis has about 250 compartments called testicular lobules .
Each lobule contains one to three seminiferous tubules.
Seminiferous tubules lined by male germ cells and Sertoli cells.
Male germ cell undergoes meiosis and produce sperm.
Sertoli cells provide nutrition to the germ cell and the sperm.
In between the seminiferous tubule there is interstitial cell or Leydig cell.
Leydig cells produce testicular hormones called androgen (testosterone).
Accessory ducts:
Includes rete testis, vasa efferentia, epididymis and vas deferens.
Seminiferous tubules open into vasa efferentia through rete testis.
The vasa efferentia leaves the testis and open into epididymis.
The epididymis leads to vas deferens that ascends to the abdomen through inguinal canal and loops over the urinary bladder.
Vas deferens receives a duct from seminal vesicle and opens into the urethra as the ejaculatory duct.
Urethra originates from the urinary bladder and extends through the penis to its external opening called urethral meatus.
Accessory glands:
Includes
Paired seminal vesicle
A prostate gland
Paired bulbourethral gland.
Secretion of these glands constitutes the seminal plasma .
Seminal plasma rich in fructose, calcium, and certain enzyme.
Secretion of bulbo-urethral glands helps in lubrication of penis.
External genitalia:
Penis is the external genitalia.
It is made of special tissue that helps in erection of the penis to facilitate insemination.
The enlarged end of penis is called glans penis .
Glans penis is covered by a loose fold of skin called foreskin.
THE FEMALE REPRODUCTIVE SYSTEM
Located in the pelvic region of the female.
The female reproductive system includes:
A pair of ovaries
A pair of oviduct.
Uterus
Cervix
Vagina
External genitalia.
A pair of mammary gland.
Ovaries:
It is the primary female sex organs that produce the female gamete (ovum).
It also produces several steroid hormones.
The ovaries located in the lower abdomen.
Each ovary is about 2-4 cm in length.
Connected to the pelvic wall and uterus by ligaments.
Each ovary is covered by thin epithelium which encloses the ovarian stroma
The ovarian stroma has two zones
A peripheral cortex.
An inner medulla.
Oviduct:
Oviducts, uterus and vagina constitute the female accessory ducts.
Each fallopian tube is about 10-12 cm long and extends from the periphery of each ovary to the uterus.
Close to the ovary the oviduct has a funnel shaped structure called infundibulum?
The edges of the infundibulum possess finger-like projections called fimbriae, which helps in collection of the ovum after ovulation.
The infundibulum leads to a wider part of the oviduct called ampulla.
The last part of the oviduct is called isthmus which joined to uterus.
CBSE Biology (Chapter Wise) Class XII ( By Mr. Hare Krushna Giri )
Email Id : [email protected]
Biology - Mr. Hare Krushna Giri
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