cells and tissues Flashcards
what are the 4 points of cell theory?
- basic structural unit of plants and animals
- smallest unit of life
- produced only by division of preexisting cells
- each maintains homeostasis
covering, lining, storage movement, connection, defense, communication, reproduction are all examples of what?
cell functions
what are the 3 parts of a cell?
- plasma membrane
- cytoplasm
- nucleus
what are the 3 main functions of the cell membrane?
barrier
gate keepers location
communcation
what are the 2 gatekeepers in the cell membrane?
ion channels
carriers
with what is the majority of the cell membranes communication?
the immune system
what kind of membrane is the plasma membrane?
a lipid bilayer
what is highly permeable in a lipid bilayer?
O2, CO2, steroids
what is moderately permeable in a lipid bilayer?
water and urea
what is impermeable in a lipid bilayer?
glucose
how can macromolecules pass through the plasma membrane?
vesicular transport
what are the two methods of vesicular transport?
endocytosis and exocytosis
what 2 gradient types occur across the plasma membrane?
concentration and electrical
what are the 3 passice processes?
simple diffusion
facilitated diffusion
osmosis
what is unique about passive processes?
moves DOWN concentration gradient
requires no energy input from cell
what uses facilitated diffusion?
ion channels
what are the 2 active processes?
active transport and vesicular transport
for sodium-potassium pump, which one goes in/out
sodium out, potassium in
what is unique about active processes?
they do require cellular energy to move AGAINST the gradient
what are the 4 types of tissue?
epithelial
connective
muscular
nervous
which tissue covers body surfaces, organs and ducts?
epithelial
which tissue forms glands
epithelial