Transport Across The Cell Membrane

Phagocytosis

Active transport involving the formation of membrane- bound vesicles to engulf solid particles

Pinocytosis

Active transport involving the formation of membrane- bound vesicles/vacuoles to engulf liquid particles

receptor mediated cytosis

Active transport involving the formation of membrane-bound vesicles/ vacuoles to engulf specific particles according to membrane receptors

facilitated diffusion

diffusion assisted by proteins in cell membrane- for molecules that can't move through phospholipids

adenosine tri phosphate (ATP)

The energy which is used to transport molecules through cell membrane

permeability

allowing liquids or gases to pass through it.

active transport

Energy-requiring process that moves a solute against its concentration gradient

Chanel mediated diffusion (facilitated diffusion)

Carrier mediated diffusion (facilitated diffusion)

when protein channels changes shapes to let a molecule through

(simple) diffusion

When molecules move directly through cell membrane, going down their concentration gradient (from high to low)

Pumps (active transport)

actively move molecules against their concentration gradients

passive transport

Does not require energy to transport a solute (down the concentration gradient)

Hypotomic

when water moves outside the cell because solute concentrate is lower outside the cell than inside- diffusion

isotonic

when water does not move anywhere because solute concentrate outside the cell is the same as inside the cell

hypertonic

when water moves inside the cell because solute concentrate inside the cell is less than outside the cell

Osmosis

diffusion of water, when the solute cannot easily cross the membrane any other way

concentration gradient

slope from high to low relative amounts of solute and solvents

Endocytosis (cytosis)

membrane infolds to bring substances into the cell

Exocytosis

membrane outfolds to move substances out of the cell

What are the three things cell membranes are made from?

1. Phospholipids (lipid bilayer) (the basic building block of the cell membrane)

2. Proteins (can act as receptors and help transport molecules inside or outside the cell)

3. Cholesterol (keeps fluidity of the membrane stable)

The role of lipids in cell membrane structure