increase cell flexibility.

diffuse neutral molecules passively into and out of cell through hydrophilic hrads and hydrohobic tails

attatch to phospholipid 

in warm temps prevent fluidity b/c prevent lipids from rotating

in cold temps lowers freezing temps thus increase fluidity

transport charged and larger molecules through active transport

can be channel or carrier

• phospholipid bilayer
• cholesterol
• cell to cell recognition
• signal transduction
• enzymatic reactions
• intercellular joining
• attachment to ctyoskelton and EMC
• transport protein

absorbs cystine and amino acids from urine and return to blood

if not present molecules crystalize and form kidney stones

drives diffusion of ions across membrane

move Na+ and K+ to generate nerve impulses

secretory, pancreas, and neuron cells

large surface area and flexible membrane allow for exocytosis

pancreas: exo to put insulin in blood

neurons: release chemicaals to stimulate nerve cells

plants deliver charbohydrates out of cell to make cell wall

cholesterol and LDL bind to recpetors and enter cell via endocytosis (synthesize membranes and steeroids)

if LDL receptors defective the cholesterol stays in blood, builds up, and clogs arteries

active transport that transsports molecules against concentration gadient

sucrose enters cell if transported with H+ on transport protein

doesnt require enrgy and molecules move down concentration and electrochemical gradient

increases entrophy and move small molecules

• diffusion-high to low until =; phospholipids
• facilitated diffusion- diffusion through protein; channel (transport) protein
• osmosis-facilitated of water; from hypo- to hyper-tonic; channel proteins

use cell enrgy to move larger charged molecules and moves against concentration gradient sometimes past =

• endocytosis-cell takes in molecule by forming new vesicles
• --phagocytosis (eating) and pinocytosis (drinking)
• exocytosis-cell secretes molecule bu fusing vesicle with membrane and releasing
• use transport (carrier) proteins-ex: sodium-potassium pump uses electrogenic pump to generate voltage across membrane

determined by SA to volume ratio

when cell increases size the volume increase as higher rate than surface area and this if too big cell unable to take in and get ridnof materials fast enough in order for survival

cells can be modified to increase SA however-overall shape (long) or folds (microvilli) in cell membrane

• cell membrane that regulates flow
• membranes have semi-fluid substance called cytosol thstbcontains organelles
• ribosomes are some of these and make proteins
• dna is at one pt in chromosome form 

domains (pro in bacteria and archae)

nucleus/no nucleus (nucleoids)

chromosomes/dna circle

organelles/no organells

large/small

compartmentalized/no comparments

cytoskeleton (change shape and maintain structure)/cell wall

mitosis/binary fission

process that facilitated the formation of mitochondria and plastids in eukaryotic cells

proof reason because characterisitics shared btwn bacteria and eukarya that arent shared with archae and vice versa