concentration gradient definition

diffusion

the net passive movement of particles from a region in which they are in higher concentration to regions of lower concentration.

concentration gradient

the process of particles moving through a solution from an area of higher number of particles to an area of lower number of particles. The areas are typically separated by a membrane.

hypotonic solution

too much water inside the cell because there is a lower concentration of solutes outside the cell than inside the cell.

symporter

transporter that carries two different ions or small molecules, both in the same direction

hydrophobic portion of plasma membrane?

two tails of phospholipid

isotonic solution

water molecules moving in and out of the cell move at the same rate. Causing the cell to have a normal shape

dynamic equailibrium

A system in a steady state since forward reaction and backward reaction occur at the same rate.

primary active transport

Active transport that relies directly on the hydrolysis of ATP. Does bring on another molecule with it

Why is cholesterol important in plasma membrane?

Cholesterol is required to build and maintain cell membranes; it regulates membrane permeability and fluidity over a wide range of temperatures.

secondary active transport

Form of active transport which does not use ATP as an energy source; rather, transport is coupled to ion diffusion down a concentration gradient established by primary active transport.

transmembrane proteins

Integral proteins that span the membrane.

structures that help with cell movement

Microtubules flagella cilia

Osmosis

Osmosis is the movement of water through a plasma membrane from a region of low solute concentration to a region of high concentration. Osmosis is passive transport, meaning it does not require energy to be applied.

Rough verses Smooth ER

Rough ER is called rough because it has ribosomes attached to its surface.

Vesicle

Small membrane-bound sac that functions in moving products into, out of, and within a cell.

quaternary structure

The fourth level of protein structure; the shape resulting from the association of two or more polypeptide subunits.

Plasma membrane structure

The plasma membrane is composed of two layers of phospholipids back-to-back. Phospholipids are lipids with a phosphate group attached to them.

cell theory

all cells come from other cells all living things are made of cells cells are the basic unit of life

Hypertonic solution

causing water to move out of the cell because there is a higher concentration of solutes outside the cell than inside the cell.

passive transport

diffusion without the use of energy

hydrophilic portion of plasma membrane?

head of phospholipid

Plasma membrane function

it regulate what enters and leaves the cell

Transporters

mechanisms in the membrane of a cell that actively transport ions or molecules across the membrane

passive diffusion

movement of substances across a semipermeable membrane with the concentration gradient; this process does not require energy

endocytosis

particles moving into the cell

exocytosis

particles moving out of the cell

active transport

requires energy, is against concentration gradient, pump

Plasma membrane

the boundary between the cell and its environment. It regulates what enters and exits the cell.

Uniporter

A carrier protein that transports a single molecule across the plasma membrane.

antiporter

A carrier protein that transports two molecules acrss the plasma membrane in opposite directions.

Na/K ATPase

3 Na out, 2 K in Both against concentration gradients Active Enzyme ATP turns to ADP releases Phosphate and switches direction of the pump.