University:
Kentucky State University
Course:
BIO 301 | Human Anatomy
Academic year:

2023
Views:

250

Pages:

11
Author:

diamundgalx45p

1. Structural glandular classification Classification based on number of cells Unicellular Gland Multicellular Glands 20 SHEET NOTE #1 We’ll talk about ( Exocrine gland ) Classification based on number of cell  structural Classification Unicellular Glands  goblet cell ( example) Today we will speak about multicellular glands and goblet cell ( unicellular) Unicellular Gland • Unicellular are single-cell gland • goblet cells • Produce mucus • Highly polarized • are common in simple cuboidal, columnar and pseudostratified epithelia of many organs. e.g. small intestine & respiratory tract 21 SHEET NOTE #2 We can divide any cell to 1. apical pool ( apical side ) 2. Basel pool ( basement membrane side) , if some organelles located in Basel side and another organelles located in apical side  that mean the cell is polarized The organelles which located in Basel pool is basophilic like ( RER and nucleus) And in apical pool  secretary granules ( carbohydrates and glycoprotein) Multicellular glands • Epithelia of exocrine glands are organized as a continuous system composed of many small secretory portions and ducts that transport the secretion out of the gland. • The structure of the secretory portions and ducts allows exocrine glands to be classified into: 22 Multicellular glands • Simple gland (ducts not branched) or compound gland (ducts with two or more branches). • Secretory portions can be tubular (either short or long and coiled) or acinar (rounded and saclike), either type of secretory unit may be branched, even if the duct is not branched. • Compound glands can have branching ducts and can have multiple tubular, acinar, or tubuloacinar secretory portions. 23 SHEET NOTE #3 All these glands are multicellular gland 2. Methods of Glandular Secretion • Merocrine - most protein secreting glands e.g. saliva & digestive enzymes (most common) • cells release their products by exocytosis from secretory vesicle. • Apocrine – lipid droplets in mammary gland • upper part of cell possibly pinches off & dies • Holocrine - sebaceous glands of skin • whole cells die & rupture to release their products 24 SHEET NOTE #4 Microcline : most common , example cells which synthesis protein ( goblet cell , saliva and digestive enzyme) Apocrine : ( lipid is synthesis in smooth ER) , like mammary gland w  whole cell 3. Classification of merocrine glands according to nature of secretion Mucus: a viscid, slimy, carbohydraterich secretion Serous: a thin, watery, protein-rich secretion (high in enzymatic Mucus & Serous SHEET NOTE #5 Mixed secretion  example ( salivary glands ) , the secretion is mixture between mucus and serious