Transport across membranes

Question 1

list the 4 types of transports across membranes

Answer 1

-passive transport
-active transport
-sodium-potassium pump
-co-transport or coupled channels

Question 2

passive transport

Answer 2

-high to low
-with gradient concentration
-NO cell energy

Question 3

List the two ways of passive transport

Answer 3

1)Simple diffusion (for water and small non-polar molecules)
directly through phospholipid bilayer through protein channel
2)Facilitated diffusion for large molecules (amino acids) and polar molecules (glucose)
carrier meditated diffusion

Question 4

List the steps of passive transport facilitated diffusion

Answer 4

1) molecule hits the binding site due to random collision
2)molecule binds to specific site
3) binding causes 3^0 structure of protein to change.
4)new shape causes molecules to flip to inside of the cell and get released
5)transport protein resumes original shape

Question 5

Active transport or carrier meditates transport

Answer 5

-against (gradient)
-low to high
-Cell energy (ATP) needed.

Question 6

Steps of active transport

Answer 6

1) molecule drawn into the binding site
2)ATP→ADP+P releases energy used to flip carrier protein
3) carrier protein resumes original shape

Question 7

Sodium potassium pump

Answer 7

Na + K are moved against their (gradient0
Cell energy is needed
-3 sodium Na transported out
-2 potassium transported in .

Question 8

Steps of sodium potassium pump

Answer 8

1) Na and K bind to thier respective binding site on the carrier protein.
2) ATP is hydrolysed releasing energy
3) energy changes 3^0 structure of the protein
4) Change in shape brings in 2k+ and sends out 3Na+

Question 9

Co transport coupled channels

Answer 9

-sodium can enter if it binds to a coupled channel.
-Chanel will only change shape (flip) if another molecule binds like aa or glucose bind too