Glands Flashcards
Gland definition
An epithelial cell or aggregate of cells which are specialised for secretion
Secretion definition
The production and release of materials by cells
3 types of secretion
Merocrine
Apocrine -
Holocrine
Merocrine secretion
Basically exocytosis
Apocrine secretion
Part of the cytoplasm is pinched off and lost
Holocrine secretion
Complete loss of cytoplasm ascen disintegrates and it’scontents are released
Exocrine gland
Secrete into a duct which leads to the intended location of the secretion
Endocrine gland
Ductless glands releasing secretions directly into the bloodstreamusuary found as cords, clusters or follicles around a blood supply
Exocytosis
Golgi vesicle fuses with membrane of cell,this reside membrane becomes parr of the main membrane releasing the vesicle contrives
Endocytosis (bulk intake)
Contents approach cell, cell membrane invaginates and surrounds material in vesicle
Pancreas = exocrine and endocrine
Exocrine acinar cells secrete into ducts
Exocrine glands often have a demilune
A cap that has a myoepithelial cell attactched to the demilune surface
Transepithelial transport
Where endocytosis and exocytosis are coupled
Material Endocytosed at one side, transported across cytoplasm by vesicle and exocytosed at the other
Use of transepithelial transport
When molecules to large to penetrate membranes they can be moved body compartments by transepithelial transport
Golgi structure
Stack of disc shaped cisternae
one end of stack is flattered other is concave
