cells and cell membranes Flashcards
plasma membrane function
regulate movement of substances in and out of cell
nucleus function
contains cells DNA
controls the cell
nucleolus function
ribosome synthesis
ER function
plays a central role in the synthesis of proteins
golgi body function
manage sort + package macromolecules for cell secretion
mitochondria function
production of energy by synthesis of ATP
nuclear envelope function
pores regulate the movement of macromolecules like protein and RNA
how many stages of protein synthesis
8
whats protein accronym
r
n
p
r
t
g
s
e
protein synthesis
ribosomes
nuclear pores
protetin synthesis
rough er
transport vesicles
golgi
secretary vesicles
exocytosis
width of cell membrane
7-8 nm
3 functions of cell membrane
1 - selectivley permeable
2 – allows communication with other cells
3 - allow recognition of other external substances
phospholipid sturcture
two Fatty acids
glycerol
phosphate group.
what do intrinsic proteins do
responsible for transport,
enzymatic activity,
cell-cell recognition, intercellular joining
what does intrinsicc protein allow
facilitated diffusion
what are carrier proteins
change in shape that translocates the solute across the membrane. This is used for larger molecules
channel proetin
hydrophilic corridors for specific hydrophilic molecules to move down
where are glycoproteins
combined to a carbohydrate (protein thingy)
glycolipid function
recognition site
where is glycolipid on membrane
behidn the bilayer thingy
cholesterol function
adds strength and rigidity to the membrane
intrinsic protein function
span the whole membrane allows facillitated diffusion
extrinsic proteins function
only on surface of membrane anchor cells to other structures
glycoproteins function
cell receptor sites
hormone / drugs bind to them
phospholipids function
hydrophilic head + hydrophobic tail form the fluid moasaic model
cholesterol function
provides stability by reducing the fluidity
what affects cell transport
surface area
concentration gradient
temperature
size of molecule
lipid solubility
thickness of the membrane.
2 types of transport
passive
active
conc gradient with passive transport
with
conc gradient with active transport
against
needs energy
3 types of passive transport
Diffusion
Facilitated diffusion
Osmosis
diffusion
down a concentration gradient
passive process
why is diffusion essential in the body
exhcnage of gases in alevolus iin the cell
effect of conc gradient on diffusion
greater concentration difference, faster substance will diffuse
effect of distance of travel on diffusion
further a particle mst diffuse, longer it will take and slow rate of diffusion
effect of surface area of membrane on diffusion
greater surface area, greater probibility that a particle will pass through
effect of thickness of membrane on diffusion
thicker the longer it takes for particles to pass through
effect of increase in temp on diffusion
rate of diffusion will be faster as temp increases de to greater kinetic energy
effect of particle size on diffusion
at given temp, small particles moves faster than a large one
carrier proteins
will bind to the substance and then change their shape so that the substance is transported to the other side of the membrane
channel proteins
contain hydrophilic tunnels which water soluble particles such as ions can travel through
what affects the rate of facillitated diffusion
number of channel or carrier proteins
osmosis
movement of water from an area of high water concentration to an area of low water concentration across a partially-permeable membrane
active transport
process cell takes up a substance against a concentration gradient from a low concentration to a high concentration
endoctosis
Transports large molecules into a cell.
Molecules enclosed in fold in membrane that pinches shut to form a vesicle.
Energy is needed in the form of ATP
exocytosis
Transports large molecules out of a cell.
Molecules are enclosed by a vesicle (from endoplasmic reticulum or golgi body) and fuses with the membrane.
Energy is needed in the form of ATP
what is pinocytosis
uptake of large molecule form solution
what is phagocytosis
up take of solid particles
baisic explination of endocytosis
bulk transport into the cell
baisic explination of exocytosis
bulk transport out of cell
how to leave the cell
exocytosis
material package in vesicles
vesicles fuse with plasma membrane
