Transport across Membrane

Question 1

Phospholipid Bilayer

Answer 1

Phosphate head - Hydrophilic molecules will bind
Glycerol
Fatty acid tails (one saturated, one unsaturated) - Hydrophobic molecules will bind

Question 2

Simple Diffusion

Answer 2

Passive movement of molecules across a membrane, down/along concentration gradient

Question 3

Down a concentration gradient

Answer 3

From areas of high solute concentration to ares of low solute concentration

Question 4

Facilitated Diffusion

Answer 4

Passive movement of molecules or ions across a membrane via embedded/transmembrane integral proteins, down/along concentration gradient

Question 5

Channel Proteins

Answer 5

Form open pores through membrane allowing free diffusion of any molecules of appropriate size and charge (ion selective and polar (H2O) molecules)

Question 6

Carrier Proteins

Answer 6

Bind with specific molecules to be transported from one side of membrane to the other
Undergo conformational changes to allow molecule to pass through & be released on other side
Opened and closed in response to nerve impulse, as molecules binds

Question 7

Protein Pumps

Answer 7

Used in active transport to move molecules with/against concentration gradient
Capable of pumping molecules through membrane as the pump changes shape to allow for this

Question 8

Osmosis

Answer 8

The net movement of water molecules across a semi-permeable membrane, down/along concentration gradient
Water is the solvent, so moves from areas of low solute concentration to areas of high solute concentration