Epithelium 2: Glands Flashcards
What are the types of glands?
Exocrine glands
Endocrine glands
Mixed glands
What are exocrine glands?
Pass secretions through a duct system onto an epithelial body surface
Secretions are normally enzymes
What are endocrine glands?
Pass secretion directly into blood or lymph (internal secretion)
Secretions are normally hormones
What are mixed glands?
Have both exocrine and endocrine components
How can exocrine glands be classified?
Based on shape of secretory unit & branching pattern of duct
Based on mechanism of release of their product
Based on the nature of their secretion
How can glands be classified according to number of cells?
Unicellular glands: Single secretory cells, e.g. goblet cells
Muticellular glands: Group of epithelial cells which discharge secretion directly or through duct systems, e.g. parotid glands
How can glands be classified according to the structure of the duct?
Simple
Compound
Characteristics of simple glands
Unbranched excretory ducts
Contain a single secretory unit
Types of simple glands
Characteristics of compound glands
Excretory duct is branched
Bulky and contain many individual secretory units
Types of compound glands
Examples of complex glands
What are the classifications of glands according to their mode of secretion?
Holocrine
Apocrine
Merocrine
Characteristics of holocrine glands
Whole cell dies and the discharges go together with cellular contents
E.g. sebaceous and tarsal gland cells
Characteristics of apocrine glands
Small portion of cell body lost during secretion
E.g. mammary glands