histology

Question 1

tissue

Answer 1

mass of similar cells and cell products
- perform specific functions
- composed of cells and matrix

Question 2

matrix

Answer 2

extracelluar material
- surrounds cell
- liquid, semisolid, or solid
- composed of fiber and ground substances

Question 3

ground substance

Answer 3

clear, featureless material
- fibers and cells of a connective tissue are embedded

Question 4

4 primary tissue classes

Answer 4

• epithelial
• connective
• muscular
• nervous

Question 5

epithelial tissue

Answer 5

• consists almost entirely of cells
• covers body surfaces, cavities, linings, and forms glands (ex: skin, digestive or respiratory cavities, heart and blood vessels)
• has free (apical) surface and basal surface
• avascular yet regenerative
• specialized cell contacts\

Question 6

specialized cell contacts (junctions)

Answer 6

• certain arrangements of protein at the cell surface
• found on lateral and basal surfaces of cells
• types: desmosomes, tight junctions, gap junctions

Question 7

tight junctions

Answer 7

join the cell tightly to neighboring cells, form permeability barrier (can not leak)
- stomach and urinary bladder

Question 8

desmosomes

Answer 8

often found in areas that are subjected to stress
- epithelium of the skin

Question 9

gap junctions

Answer 9

• connexons: allows ions and small molecules to pass through
• coordinates function of cardiac and smooth muscles

Question 10

epithelial tissue - shapes

Answer 10

• squamous
• cuboidal
• columnar

Question 11

epithelial tissue - layers

Answer 11

simple epithelium
stratified epithelium

Question 12

simple epithelia

Answer 12

types:
- simple squamous
- simple cuboidal
- simple columnar
- pseudostratified columnar

Question 13

simple squamous epithelium

Answer 13

appearance:
- single layer: thin cells, “fried egg” appearance, thin cytoplasm

function:
- rapid transport of substances through membranes

representative locations
- alveoli of lungs
- kidney tubules
- endothelium
- mesothelium

Question 14

simple cuboidal epithelium

Answer 14

appearance:
- square or round cells, tightly fitted
- centrally placed nuclei
- microvilli border (sometimes)

function:
- absorption, secretion, production and movement of respiratory mucus

representative locations:
- liver
- glands
- most kidney tubules
- bronchioles

Question 15

simple columnar epithelium

Answer 15

appearance:
- single layer
- tall, narrow cells, vertically oriented
- oval shaped nuclei, near base
- microvilli or cilia
- goblet cells

function:
- absorption, secretion, movement

representative locations:
- inner lining of: stomach, intenstines, uterus and uterine tubes
- some kidney tubules