Unit 2 / Chapter 4 / Histology Flashcards
Histology
The study of the normal structure of tissues.
Histology
What is the MAJOR tissue type?
Coverings and linings, skin, sheets of cells on top of basement membrane, edges face air or fluid
Epithelium
What is the MAJOR tissue type?
Holds tissues together, bind, support, protect, allows transport, fibers, goo
Connective
What is the MAJOR tissue type?
Movement, contracts to generate force, skeletal, cardiac, smooth
Muscular
What is the MAJOR tissue type?
Information, communication, conduction of electrical impulses, also cells which support the information cells’ function
Nervous
Type of junction:
Impermeable; no passage of macromolecules between cells.
Ex: BBB - blood brain barrier
Tight Junction
Type of junction:
Resist mechanical stress, but ECM molecules can pass between cells. Ex: skin cells in epidermis
Desmosomes
Type of junction:
Small pores in protein channels. Allows free passage of small substances between the cytosol of 2 cells.
Ex: cardiac muscle
Gap Junction
Epithelium type:
Function: Absorption, secretion, filtration (gas exchange), production of fluid in serous membranes
Location: air sacs of lungs, serous membranes, kidney glomeruli, endothelial lining of vessels.
Simple Squamous Epithelium
Epithelium type:
Flat cells with central nucleus, 1 layer
Simple Squamous Epithelium
Epithelium type:
Function: secretion and absorption
Location: kidney tubules, ducts of glands, thyroid, respiratory
Simple Cuboidal Epithelium
Epithelium type:
1 layer, cells are as tall as wide, square appearing with large central nucleus
Simple Cuboidal Epithelium
Epithelium type:
Function: absorption, secretion, also propulsion where ciliated
Location: stomach, small intestine, colon, gallbladder, kidney tubules, uterine tube
Specialized features: microvilli, cilia, goblet cells
Simple Columnar Epithelium
Epithelium type:
1 layer, cells taller than wide, nuclei toward base
Simple Columnar Epithelium
Epithelium type:
Function: protection from mechanical stress, microbes, (skin: also dehydration)
Location: skin (keratinized);
mouth, throat, esophagus, anus, vagina (nonkeratinized)
Stratified Squamous Epithelium
Epithelium type:
More than 1 layer, flat, stacked cells, round w/ nuclei near basement membrane, flatter near surface
Stratified Squamous Epithelium
Epithelium type:
Function: cilia for propulsion, secretion, goblet cells produce mucus
Location: respiratory tract: nasal, tracheal; also portion of male urethra
Pseudostratified Ciliated Columnar Epithelium (PCCE)
Epithelium type:
1 layer, looks like more, closely packed columnar cells, nuclei at different heights, goblet cells
Pseudostratified Ciliated Columnar Epithelium (PCCE)
Epithelium type:
Function: stretch/distensibility - cells look more flat when structure that they line is distended.
Location: urinary tract from renal pelvis, ureter, bladder, urethra
Transitional Epithelium
Epithelium type:
squamous-to-cuboidal (multiple cell layers, so stratified)
Transitional Epithelium
Structures which forms and secretes a product.
Glands
Structure that secretes products to the bloodstream.
Endocrine Glands
Structure that releases products to epithelial surface or into ducts.
Exocrine Glands
Exocrine Gland:
Unicellular and releases mucus to digestive and respiratory tracts.
Goblet Cell