Biology MALE REPRODUCTIVE SYSTEM

KEY TOPICS

`star` Introduction
`star` Testes
`star` Male External Genitalia
`star` Male Accessory Ducts
`star` Male Accessory Glands

INTRODUCTION

● `color{Brown}"Location"`: The male reproductive system is located in the `color{Violet}"pelvis region"`.

● `color{Brown}"Components"`: It includes a pair of `color{Violet}"testes"` (gonad) along with `color{Violet}"accessory ducts"`, `color{Violet}"glands"` and the `color{Violet}"external genitalia"`.

TESTES

● `color{Brown}"Location"`: The testes are situated `color{Violet}"outside"` the `color{Violet}"abdominal cavity"` within a pouch called `color{Violet}"scrotum"`.

● `color{Brown}""`Function of scrotum: The scrotum helps in maintaining the `color{Violet}"low temperature"` of the testes (`color{Violet}"2–2.5 degree celsius"` lower than the normal internal body temperature) necessary for `color{Violet}"spermatogenesis"`.

● `color{Brown}"Dimensions of Testes"`: In adults, each testis is `color{Violet}"oval"` in shape, with a length of about `color{Violet}"4 to 5 cm"` and a width of about `color{Violet}"2 to 3 cm"`.

● The testis is covered by a `color{Violet}"dense covering"`.



● `color{Brown}"Components of Testes"`:
`star` Each testis has about `color{Violet}"250"` compartments called `color{Violet}"testicular lobules"`.

`star` Each lobule contains one to three `color{Violet}"highly coiled"` `color{Violet}"seminiferous tubules"` in which sperms are produced.

`star` Each seminiferous tubule is `color{Violet}"lined"` on its inside by two types of cells called male germ cells (`color{Violet}"spermatogonia"`) and `color{Violet}"Sertoli cells"`.

`star` The regions outside the seminiferous tubules called `color{Violet}"interstitial spaces"`, contain small blood vessels and `color{Violet}"interstitial cells"` or `color{Violet}"Leydig cells"`.

● `color{Brown}"Functions"`:
The male germ cells undergo `color{Violet}"meiotic divisions"` finally leading to `color{Violet}"sperm"` formation.

`star` The sertoli cells provide `color{Violet}"nutrition"` to the germ cells.

`star` Leydig cells synthesise and secrete `color{Violet}"esticular hormones"` called `color{Violet}"androgens"`.

`star` Other `color{Violet}"immunologically competent"` cells are also present.

MALE EXTERNAL GENETALIA

● The `color{Violet}"penis"` is the male external genitalia.

● It is made up of `color{Violet}"special tissue"` that helps in erection of the penis to facilitate `color{Violet}"insemination"`.

● The enlarged end of penis called the `color{Violet}"glans penis"` is covered by a loose fold of skin called `color{Violet}"foreskin"`.

MALE ACCESSORY DUCTS

● `color{Brown}"Components"`: The male sex accessory ducts include `color{Violet}"rete testis"`, `color{Violet}"vasa efferentia"`, `color{Violet}"epididymis"` and `color{Violet}"vas deferens"`.

● The seminiferous tubules of the testes open into the `color{Violet}"vasa efferentia"` through `color{Violet}"rete testis"`.

● The vasa efferentia leave the testis and open into `color{Violet}"epididymis"` located along the `color{Violet}"posterior surface"` of each testis.

● The epididymis leads to `color{Violet}"vas deferens"` that ascends to the abdomen and loops over the urinary bladder.

● It receives a duct from `color{Violet}"seminal vesicle"` and opens into urethra as the `color{Violet}"ejaculatory duct"`.

● These ducts `color{Violet}"store and transport"` the sperms from the testis to the outside through `color{Violet}"urethra"`.

● The urethra originates from the `color{Violet}"urinary bladder"` and extends through the penis to its `color{Violet}"external opening"` called `color{Violet}"urethral meatus"`.

MALE ACCESSORY GLANDS

● `color{Brown}"Components"`: The male accessory glands include paired `color{Violet}"seminal vesicles"`, a `color{Violet}"prostate"` and paired `color{Violet}"bulbourethral glands"`.

● `color{Brown}"Functions"`:
`star` `color{Violet}"Secretions"` of these glands constitute the `color{Violet}"seminal plasma"` which is rich in `color{Violet}"fructose"`, `color{Violet}"calcium"` and certain enzymes.

`star` The secretions of bulbourethral glands also help in the `color{Violet}"lubrication"` of the penis.


 
SiteLock