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Basic unit of life

syntehsis of molecules

specialized structures in cells that perform specific functions

ex. nucleus, mitochondria, ribosomes

jelly-like substance that holds organelles

outermost component of a cell

it is the selective barrier and it encloses cytoplasm

material outside cell

material inside cell

also called as fluid mosaic model

it is made of phospholipids and proteins

it forms a double layer or bilayer

two regions of phospholipids

"heads"
hydrophilic
exposed to water

"tails"
hydrophobic
away from water

phosphate containing region

fatty acid containing region

it selectively determines what can pass in and out of the cell

these are found in higher concentrations INSIDE the cell

are found in higher concentrations OUTSIDE the cell

WAYS MOLECULES PASS THROUGH CELL MEMBRANE

molecules pass through O2 and CO2

proteins that extend from one side of cell membrane to other

size, shape, and charge determine what can go through

bind to molecules, transport them across, and drop them off

can transport a variety of materials

fuse with cell membrane

movement of molecules from areas of high to low concentration

contains one or more solutes

substance added to solvent that dissolves

substance such as water that solute is being added to

measures concentration difference at 2 points

greater the distance, the faster the solute will travel

movement of fluid through a partition with holes

MEDIATED TRANSPORT MECHANISMS

diffusion with aid of a carrier molecule

it requires no ATP

moves substances from low to high concentration

this requires ATP

diffusion of water across a cell membrane

force requiredd to prevent movement of water across cell membrane

TYPES OF OSMOTIC SOLUTIONS

lower concentration of solutes outside cell
higher concentration of water outside cell

water moves into cell
lysis (burst)

higher concentration of solutes outside cell
higher concentration of water inside cell

water moves out
crenation (shrinks)

equal concentration of solutes
water doesn't move
cell remains intact

process that brings materials into cell using vesicles

TWO TYPES OF ENDOCYTOSIS

cell eating (solid particles)

cell drinking (liquid particles)

process that carries materials out of cell using vesicles