chapter 2- cells Flashcards
3 main parts of cell
nucleus, cytoplasm, plasma membrane
what stabilizes plasma membrane
cholesterol
heads of phospholipid bilayer
water soluble, form surface
tails of phospholipid bilayer
water insoluble, form interior
fluid mosaic
membrane proteins that float through fluid membrane creating a constantly changing environment
3 types of extracellular fluid
interstitial, blood plasma, lymph
passive process
require no cellular energy (ATP)
active processes
requires cellular energy (ATP)
3 types of passive processes
simple diffusion, facilitated, osmosis
3 types of active processes
active transport, endocytosis, exocytosis
simple diffusion/concentration gradient
movement of small particles like oxygen from high # of particles to low
facilitated diffusion
diffusion across membrane with help of channel or carrier molecules. large molecules like glucose and amino acids cant pass through.
osmosis
same as concentration gradient but specific to water
water follows
solutes (salt)
isotonic
same osmotic pressure or number of solutes in cell and solution