L9 Transport Across Cell Membrane

Question 1

What are the 3 types of passive transport

Answer 1

Osmosis
Simple diffusion
Facilitated diffusion

Question 2

What is passive transport

Answer 2

Transport of substances down a concentration or electrochemical graduent
May need carrier protiens

Question 3

What is simple diffusion

Answer 3

Passive process in wbich subtances move freely through the lipid bilayer of plasma membranes of cells without need for tranport proteins
Ex O2 CO2 nitorgen gases steriods fatty acids fat soluble vitamins

Question 4

What is facilitated difussion

Answer 4

a)channel meditated: solute moves down conc gradient through integral transmembrane proteins
Either voltage gated
Or ligand gated
b)carrier mediated
Larger mol cannot diffuse through prt channels so they diffuse through with the help of carrier proteins

Question 5

What are VG channels

Answer 5

Open when there is a change in electrical potential

Question 6

What is a Ligand gated channel

Answer 6

Opened by binding to a ligand as some hormonal substances

Question 7

What is osmosis

Answer 7

Type of passive diffusion where there is net movement of water or any other solvent through a semi permeable membrane from area of high water conc to area of low water conc

Question 8

How do water mol pass through the membrane during osmosis

Answer 8

By moving between neighbouring phospholipid mol in lipid bilayer via simple diffusion or throigh aquaporins

Question 9

What is active transport

Answer 9

Movement of substances against the chemical or electrical or electrochemical gradient and requires energy

Question 10

How can energy be obtained for active transport

Answer 10

By hydrolsis of ATP or energy stored in an ionic conc gradient in secondary active transport

Question 11

What are the 2 types of carriers

Answer 11

Symporters: carriers that move 2 substances in the same direction at the same time
Antiporters: carriers that move 2 substances in oppisite directions across the memrane at the same time