Histology & Epithelial Tissue Flashcards
What is Histology?
The study of tissues.
What two things make up tissues?
Cells and Matrix
What is a Matrix?
Extracellular, non-living material
What are the four primary tissue types?
Epithelial, Connective, Muscle, Nervous
What are the three types of intercellular junctions?
Tight junctions, Desmosomes, Gap junctions
What is a tight junction?
Found in lining cells, help close the space between cells.
What are desmosomes?
“spot welds” between cells that are located among outer skin cells.
What are gap junctions?
tubular channels between cells found in cardiac muscles.
What does Epithelial tissue do?
Lines cavities and organs, have a free surface and a basement membrane, are avascular, and function in protection, absorption, and excretion.
How is epithelial tissue classified?
By number of layers, cell shape, and special types
What is simple squamous?
single layer of flat cells, allows diffusion. Line air sacs, blood vessels, and lymphatic vessels.
What is simple cuboidal?
single layer of cuboidal cells, line kidney tubules, ovaries, and some glands.
What is simple columnar?
single layer of elongated cells, nuclei stay low, sometimes have cilia, microvilli, goblet cells. Line uterus, stomach, intestines.
What is a Goblet cell?
cells that produce mucous
What is pseudo-stratified columnar?
Single layer of elongated cells, have cilia, goblet cells, line respiratory passageways.
What is stratified squamous?
Many cell layers, flat top cells, can hold keratin, outer layer of skin, line oral cavity, vagina, and anal canal.
What is stratified cuboidal?
2-3 layers, cuboidal, line ducts of mammary glands, salivary glands, and pancreas.
What is stratified columnar?
Layered cells that start on the bottom as cuboidal but as they approach the top layer elongate into columnar. Line male urethra and pharynx.
What is transitional epithelium?
Many cell layers, cuboidal and elongated cells, line urinary track.
What are the four forms of epithelial tissue?
Glands, skin, nails, hair.
What is glandular epithelium?
specialized epithelial tissue for production and secretion of substances
What are the structural types of exocrine glands?
tubular, branched tubular, coiled tubular, branched alveolar (simple) tubular, alvolar (compound)
What are the types of glandular secretions?
Merocrine glands, Apocrine glands, Holocrine glands
Where are merocrine glands located and what do they produce?
Salivary glands, pancreas glands, sweat glands, they produce fluid product.
Where are apocrine glands located and what do they produce?
Portions of cells, mammary glands, ceruminous glands, they produce cellular product.
Where are holocrine glands located and what do they produce?
Whole cells, sebaceous glands, they produce secretory products.
What are the two types of glandular epithelium?
Endocrine (ductless, hormones)
Exocrine (ducts, uni- and multi- cellular)
