EPITHELIAL TISSUE Flashcards
SIMPLE EPITHELIUM TYPES
SQUAMOUS CUBOIDAL COLUMNAR CILIATED (PSEUDOSTRATIFIED AND GLANDULAR )
THE TERM ‘EPITHELIUM’ INTRODUCED BY
RUYSCH
Glands are composed of … type of tissue
epithelium
basic structure of epithelium tissue
a basal surface and a free surface(faces either body fluid or outside environment)
; little intercellular material between the cells. The Basal surface lies in contact with a delicate non-cellular layer called basement membrane (provides elastic support and also anchors the epithelial tissue to the underlying connective tissue for obtaining nutrients.)
SQUAMOUS EPITHELIUM AKA
PAVEMENT EPITHELIUM/ TESSELLATED EPITHELIUM
LOCATION OF SQUAMOUS EPITHELIUM
INNERMOST WALL OF BLOOD VESSELS AIR SACS (ALVEOLI) OF LUNGS LYMPH VESSELS WALL OF BOWMAN'S CAPSULE LOOPS OF HENLE of the nephrons of the kidney coelomic cavities etc
functions of squamous epithelium
Filtration in bowman’s capsule
exchange of gases
exchange of material between blood capillaries and tissue fluid
the term ‘Tissue’ was given by?
Bichat
Study of tissue?
Histology (term introduced by Mayer)
The cells of Epithelium are ——– packed with ——– intercellular matrix.
Closely; Little.
Simple Epithelium functions as
as a lining for body cavities, ducts & tubes.
Location of Squamous Epithelium
Innermost wall of blood vessels, air sacs of alveoli, lymph vessels, wall of Bowman’s capsule, loops of Henle, coelomic cavities etc.
Function of Squamous Epithelium
Filtration in Bowman’s capsule;
Exchange of gases;
Exchange of materials bw blood capillaroes and the tissue fluid.
Nuclei in Cuboidal Epithelium
rounded & lie in the centre of cells
Location of Cuboidal Epithelium
tubular parts of nephron; ducts of glands; thyroid follicles; ovaries & testes;;
PCT has brush bordered cuboidal epithelium
Function of Cuboidal Epithelium
Secretion and Excretion by glands; in PCT - reabsorption of useful substances.
Produces gametes, ova and sperm in ovaries & seminiferous tubules of the testes (germinal epithelium)
nuclei in columnar epithelium
somewhat elongated, lie near the bases of the cells.
Mucus producing Columnar Epithelium?
Goblet Cells.
Location of columnar epithelium
Lining of Stomach & Intestine.
Function of columnar epithelium
Absorption & Secretion.
Function of cilia in ciliated epithelium
to move particles or mucus in a specific direction over the epithelium
Ciliated Cuboidal Epithelium occurs in
Smaller Bronchioles
Ciliated Columnar Epithelium occurs in the
inner surface of hollow organs like fallopian tubes and most of respiratory tract.
Function of ciliated epithelium.
Passage of Ovum through oviduct; Expelling the mucus and particles trapped in it towards the pharynx.
Nuclei in Pseudostratified Epithelium
long cells - oval nuclei; short cells - rounded nuclei
Location of pseudostratified epithelium
pseudostratified ciliated columnar epithelium - Trachea & Large Bronchi.
pseudostratified NON ciliated columnar epithelium - Urethra of human male, large ducts parotid salivary gland etc.
Epithelium cells specialized for secretion
Glandular Epithelium.
Unicellular Glands
Goblet Cells of the alimentary canal (mucous cells or Mucocytes)
