THE BREAST

They are accessory organs of reproduction. They are 2 in number and also exist in the male in a rudimentary form. They are mammary or compound secreting glands, composed of glandular tissues arranged in lobes, each breast consist of about 20 lobes made up of a number of lobules that consist of alveoli and ducts. The alveoli containacini cells which produce milk and are surrounded by myoepithelial cells which contracts and propel the milk out. Small lactiferous ducts carries milk from the alveoli and unite to form larger duct, one large duct leaves each lobe and widen to form a lactiferous sinus or ampulla which acts as a temporary reservoir for milk. A lactiferous tubule from each sinus emerges on the surface of the nipple. Each breast functions independently of the other.

The nipples are small conical projections at the centre of each breast. They are surrounded by a pigmented area called the areola. On the surface of the areola are numerous sebaceous glands which lubricate the nipples during lactation (Montgomery’s glands). The nipples compose of erectile tissue covered with epithelium and contain plain muscle fibres which have sphincter-like action in controlling the flow of milk.

The breast matures at puberty under the influence of oestrogen and progesterone, which equally enhances more growth during pregnancy. After childbirth the hormone prolactin from the anterior pituitary stimulates the production of milk, while oxytocin from the posterior pituitary stimulates the release of milk in response to the suckling motion by the baby generating positive feedback.


Function

Production of milk for lactation


THE BONY PELVIS

Bony pelvis: is made up of four bones: 

 

TYPES OF PELVIS

Gynecoid Pelvis  

Platypelloid   Pelvis

Android Pelvis

Anthropoid Pelvis