$\Delta$ It is spread on pectorialis major muscles.

A diagrammatic sectional view of Mammary gland

Mammary gland is a modified sweat gland.

A functional mammary gland is characteristic of all female mammals.

It is a paired structure that contain glandular tissue and variable amount of fat.

Externally each breast is a raised structure and nipples are located in the middle.

– Nipple is covered with light pink or light brown coloured skin having pigments. It is called areola.

The glandular tissue of each breast is divided into $15-20$ mammary lobes containing clusters of cells called alveoli.

– The cells of alveoli secrete milk which is stored in the cavities of alveoli.

– The alveoli open into mammary tubules.

$\Rightarrow$ The tubules of each lobe join to form a mammary duct.

$\Rightarrow$ Several mammary ducts join to form a wider mammary ampulla which is connected to lactiferous through which milk is sucked out.

$\Rightarrow \quad$ More information :

$\rightarrow$ Accessary reproductive gland in females.

$\Rightarrow$ The genital pore covers paraurethral glands and ducts of Bartholin's glands.