Merocrine (or eccrine) is a term used to classify
exocrine gland
Exocrine glands are glands that secrete substances on to an epithelial surface by way of a duct. Examples of exocrine glands include sweat, salivary, mammary, ceruminous, lacrimal, sebaceous, prostate and mucous. Exocrine glands are one of two ...
s and their secretions in the study of
histology
Histology,
also known as microscopic anatomy or microanatomy, is the branch of biology which studies the microscopic anatomy of biological tissues. Histology is the microscopic counterpart to gross anatomy, which looks at larger structures vis ...
. A cell is classified as merocrine if the secretions of that cell are excreted via
exocytosis
Exocytosis () is a form of active transport and bulk transport in which a cell transports molecules (e.g., neurotransmitters and proteins) out of the cell ('' exo-'' + ''cytosis''). As an active transport mechanism, exocytosis requires the use o ...
from secretory cells into an
epithelial-walled duct or ducts and then onto a bodily surface or into the
lumen.
Merocrine is the most common manner of secretion. The gland releases its product and no part of the gland is lost or damaged (compare
holocrine
Holocrine (from Ancient Greek ὅλος; ''hólos'', “whole, entire” + κρῑ́νω; ''krī́nō'', “to separate”) is a term used to classify the mode of secretion in exocrine glands in the study of histology. Holocrine secretions are p ...
and
apocrine
Apocrine () glands are a type of exocrine gland, which are themselves a type of gland, i.e. a group of cells specialized for the release of secretions. Exocrine glands secrete by one of three means: holocrine, merocrine and apocrine. In apocrine ...
).
The term eccrine is specifically used to designate merocrine secretions from
sweat glands
Sweat glands, also known as sudoriferous or sudoriparous glands, , are small tubular structures of the skin that produce sweat. Sweat glands are a type of exocrine gland, which are glands that produce and secrete substances onto an epithelial sur ...
(
eccrine sweat glands
Eccrine sweat glands (; from Greek ''ekkrinein'' ' secrete'; sometimes called merocrine glands) are the major sweat glands of the human body, found in virtually all skin, with the highest density in palm and soles, then on the head, but much les ...
), although the term merocrine is often used interchangeably.
Examples
*
Salivary glands
The salivary glands in mammals are exocrine glands that produce saliva through a system of ducts. Humans have three paired major salivary glands (parotid, submandibular, and sublingual), as well as hundreds of minor salivary glands. Salivary gla ...
*
Pancreatic glands
* Certain
sweat gland
Sweat glands, also known as sudoriferous or sudoriparous glands, , are small tubular structures of the skin that produce sweat. Sweat glands are a type of exocrine gland, which are glands that produce and secrete substances onto an epithelial sur ...
s
References
External links
Diagram at uwa.edu.au
{{Glands
Exocrine system