Lecture 4 - Cell Biology 2 Flashcards
What are the four categories of tissues?
- Epithelium
- Connective tissue
- Muscle
- Nervous tissue
T/F: epithelia are avascular
True
Lumen
space contained in a tube
Polarity
fixed segments of a cell’s borders
Apical
border or surface facing the lumen
Basal
surface adjacent to the underlying connective tissue matrix
Lateral
surface facing /attached to adjacent cells in the tissue
What are the two ways epithelia are classified
- number of layers
- shape of cell
one layer
simple
> 2 layers
stratified
flat
squamous
cube-shaped
cuboidal
tall and skinny
columnar
Simple squamous
diffusion
walls of capillaries, alveoli
Simple cuboidal
lines secretory ducts
renal tubules
Simple columnar
lines secretory or absorptive surfaces
small intestine
stratified squamous
found where physical abrasion is common
skin and mucosal cavities
stratified cuboidal
protects against chemical abrasion, contributes to the secretion
mammary gland
Stratified columnar
secretion and protection
male urethra
Pseudostratified columnar
mucus secretion
trachea
Transitional
ability to stretch and return to normal
bladder
Basement membrane functions
1 - separates epithelium from underlying connective tissue
2 - angiogenesis
3 - filtration barrier
4 - barrier against malignant cells
Microvilli
absorption
Cilia
highly motile, move mucus and other secretions
Stereocilia
very long and specialized
non-motile
male genitalia
Exocrine glands
secrete substances onto epithelial surfaces via duct
Apocrine gland
budding/pinching
mammary gland
Merocrine gland
exocytosis
sweat and salivary
Holocrine gland
complete cell rupture
sebaceous gland
