Glands -
1. SEBACEOUS GLAND -
- Absent in palm and sole. Holocrine in nature.
- Branched, alveoli are present, sac like in appearance.
- Generally attached to follicle but in free form on lips, prepuce labia majoris and labia minoris.
- It's secretion is sebum, makes hair shinny & water proof.
- In sebum 7-Dehydroxy cholesterol present that react with sun rays to form Vit. D (calciferol).
2. SWEAT GLAND OR SUDDORFFIC GLAND OR SERUS GLAND -
- It is long tube like, coiled, embeded in dermis, opens out side by pore.
- Each gland consists of secretory part & a duct.
- Secretory part is greatly coiled & surrounded by myoepithelial cells assists in expelling the sweat.
- It's secretion is sweat, it consists of 95% H O, 2% minerals & CO, 3% urea.
- Sweat is meant for temperature regulation or thermoregulation or homeostatis, under control of thyroxine & sympathetic nervous system.
- Nature is apocrine i.e. with secretion some cytoplasm come out.
- In sweat, saliva, tear, lysozyme present to kill bacteria.
- When body temperature rises the sweat glands release bradykinin which dilates b.v. to loss heat quickly.