Glandular Epithelium
Glandular Epithelium

Glandular epithelium is more complex and
varied than the epithelial cells which cover
surfaces or line tubules or vessels.
Glandular Epithelium


Glandular epithelium is more complex and
varied than the epithelial cells which cover
surfaces or line tubules or vessels.
Glandular epithelium form glands which
can consist of one or more cells that make
and secrete a product.
Products

Water soluble protein
Products


Water soluble proteins
Nonpolar lipids or steroids
Classification

Glands are classified first based on the
presences or absence of a duct for the
secretory products.
Endocrine Glands


Are ductless glands
Secrete their products
directly into the
capillaries.
Exocrine Glands

secrete their products onto a body surface
or a cavity.
Exocrine Glands


secrete their products onto a body surface
or a cavity.
are classified first based on cell number
Unicellular Exocrine Glands

are made of up of single cells which
secrete their products directly through
exocytosis onto a surface.
Unicellular Exocrine Glands


are made of up of
single cells which
secrete their products
directly through
exocytosis onto a
surface.
The only major
examples are the
goblet cells and
mucous cells
Unicellular Exocrine Glands


found mixed with the
columnar epithelium
in the digestive and
respiratory tracts.
They secrete products
called mucins
(mucous),
glycoproteins that
lubricate.
Multicellular Exocrine Glands

are made up many cells and are
composed of two parts.
Multicellular Exocrine Glands

are made up many cells and are
composed of two parts:
A epithelial lined duct
 A secretory unit called the acinus

Multicellular Exocrine Glands

Supportive connective tissue surrounds
the secretory unit and provides blood
vessels and nerve fibers.
Multicellular Exocrine Glands


Supportive connective tissue surrounds
the secretory unit and provides blood
vessels and nerve fibers.
The shape of the duct and of the
secretory unit provides for another level of
classification.
Duct Structure

Simple- unbranched, straight duct
Duct Structure


Simple- unbranched, straight duct
Compound- branched duct
Secretory Unit:

Tubular- if the secretory unit has the same
diameter throughout like a tube
Secretory Unit



Tubular- if the secretory unit has the same
diameter throughout like a tube
Alveolar- if the secretory unit is in the
shape of a flask
both of these terms refer to the acinus or
secretory unit.
Examples
Method of Secretion

Glands regardless of type (unicellular or
multicellular) can have one of two types of
secretory processes:
Method of Secretion


Glands regardless of type (unicellular or
multicellular) can have one of three types
of secretory processes:
Merocrine- products are secreted by
exocytosis. This is seen with most glands.
Method of Secretion



Glands regardless of type (unicellular or
multicellular) can have one of three types of
secretory processes:
Merocrine- products are secreted by
exocytosis. This is seen with most glands
Holocrine- the cell ruptures and releases the
product. New cells replace the spent cells. The
only example in humans are the sebaceous
(sweat) glands
Method of Secretion

Apocrine-the top of the cell pinches off.
Possibly seen in the lactating mammary
gland although this is generally considered
merocrine in nature.