Epithelia: Glands Flashcards
What do membrane channels allow
Movement of specific molecules down their concentration gradients and are typically gated controlling open or close
What is endocytosis
Material from outside the incorporated into cell by endocytosis
The cell membrane invaginates fuses and newly made endocytosis vesicle buds into the cell
Receptor mediated
What is exocytosis
Works in revers to endocytosis
What is phagocytosis
Bacteria incorporated into cell by phagocytosis
Bacterium bonds to cell surface receptors triggered forming phagosome
The phagosome bonds to lysosomes which forms a phagolysosome
Residual body
Where is endocrine gland secretions from
Product secreted towar basal end of cell the distributed by the vascular system throughout the body - ductless
How do exocrine glands secrete their product
Product secreted towards apical end of the cell either into the lumen of an internal space into a duct or onto the body surface termed ducted glands
Give some examples of endocrine glands
Pituitary glands Thyroid glands Thymus glands Pancreas Adrenal glands Ovaries/testes
What is the functional unit of the thyroid gland
Thyroid follicle
What is a follicle lined by
Low cuboidal when inactive but nearly columnar when active
Give some examples of exocrine glands
Lacrimal glands Salivary glands Mammary glands Liver Pancreas Burners glands Sweat glands Sebaceous glands
How are exocrine glands classified
Mechanism of release of secretory product Type of secretory product Number of secretory cells Duct morphology Arrangement of secretory cells
What are the types of secretion in exocrine glands
Merocrine
Apocrine
Holocene
What is merocrine secretion
Exocytosis Eccrine secretion Typically at apex of cell Most common form of secretion Product usually protein Examole - digestive enzymes in pancreas
What is apocrine secretion
Occurs when meme bound vesciles including sec products and a small amount of cell cytoplasm are pinched off from cell into extracellular space still surrounded by cell mem
Occurs at Apex of cell
Unusual form of secretion
Lipid rich
Examples fat component of milk secretion form mammary gland
What is holocrine secretion
Occurs when whole secretory cell are released from the epithelium and disintegrate discharging their contents
Product is lipid rich
Example is sebaceous glands of the skin
