Topic 1.4 Membrane Transport

Question 1

what are the three types of membrane transport?

Answer 1

simple diffusion, facilitated diffusion, and osmosis

Question 2

why is the membraned called the “fluid membrane”?

Answer 2

the phospholipid heads can move around and be permeable

Question 3

the membrane is referred to being ( _ _ _ _)permeable

Answer 3

selectively

Question 4

passive transport does not require…

Answer 4

energy, ATP

Question 5

what concentration gradient do particles move in in passive transport?

Answer 5

higher to lower

Question 6

what kind of particles go through simple diffusion?

Answer 6

not charged (nonpolar) particles

Question 7

what kind of particles go through facilitated diffusion?

Answer 7

small charged (polar) particles can still go through passive transport with the use of channels

Question 8

what is a specific example of facilitated diffusion?

Answer 8

potassium channels

Question 9

what kind of particles go through osmosis?

Answer 9

water

Question 10

what are the three types of solutions where osmosis can occur?

Answer 10

hypertonic, hypotonic, and isotonic

Question 11

which is the solution that has less solutes hence causing water the move into the tissue?

Answer 11

hypotonic

Question 12

which is the solution that has more solutes hence causing water to move out of the tissue?

Answer 12

hypertonic

Question 13

which solution has same amount of solute as water and hence water transports in and out of the tissue at equal rates?

Answer 13

isotonic

Question 14

how is active transport defined as?

Answer 14

movement of particles against the concentration gradient

Question 15

what does active transportation require?

Answer 15

ATP (energy)

Question 16

what are two types of active transport?

Answer 16

vesicle transports and protein pumps

Question 17

what aspect of membranes allow for vesicle transport to be possible?

Answer 17

its fluidity

Question 18

what is endocytosis?

Answer 18

when vesicles transport materials inside the cell

Question 19

what is exocytosis?

Answer 19

when vesicles transport materials to the outside of the cell

Question 20

what organelle creates vesicles to secret materials?

Answer 20

the Golgi Apparatus

Question 21

how do protein pumps work?

Answer 21

chemicals and ATP bind against one side of the pump and the ATP splits, releasing energy. This causes the pump to open and the chemical to move across the membrane

Question 22

outline how a sodium-potassium pump works

Answer 22

• the pump recieves 3 Na molecules and an ATP
• the ATP transfers its P group to the pump, opening the pump and sending the ion into the cell
• 2 potassium ions then bond to the inside of the cell and with the release of the previously transferred P group the potassium ions get released outside of the cell

Question 23

outline how sodium potassium channels work

Answer 23

• the gate is closed when the membrane charge is negative
• the gate opens only when the charge becomes positive
• when the gates are open the positive potassium ions squeeze through and go outside the cell making the inside of the cell more negative
• hence the gate closes again