Membrane Transport

Question 1

Simple Diffusion

Answer 1

Gets energy from the concentration gradient, and molecules which use simple diffusion and move through lipid bilayer

Question 2

Facilitated diffusion

Answer 2

Substrate still moves using the concentration gradient but uses a membrane protein to move substrate across the cell membrane

Question 3

Primary active transport

Answer 3

Requires energy from ATP and substrate can fit inside and active site of a membrane protein

Question 4

Secondary active transport

Answer 4

requires a membrane protein, creates a concentration gradient.

Question 5

Endocytosis

Answer 5

Uses vesicles to move large substrate into cells

Question 6

Exocytosis

Answer 6

Uses vesicles to move large substrates out of the cell

Question 7

Fick’s Law of membrane diffusion

Answer 7

1 Thickness of membrane 
2 Surface area of membrane 
3 size of concentration gradient 
4 Temperature
5 How permeable the membrane is

Question 8

Gated channels

Answer 8

Have some type of gate that when triggered by a ligand binding to the protein or a change in voltage will either close or open the channel.

Question 9

Leak channel

Answer 9

Always stays open to allow exchange of substrate between ECF and ICF

Question 10

Carrier proteins never?

Answer 10

open on both sides of the membrane

Question 11

uniporters

Answer 11

Move one substrate at a time through the membrane

Question 12

symporters

Answer 12

Move two substrate at the same time into the cell like SGLT transporters with glucose and sodium

Question 13

antiporters

Answer 13

Move substrates in opposite directions like sodium potassium pump

Question 14

Small numbers of ions have what kind of impact on membrane potential difference?

Answer 14

they have a massive impact on membrane potential difference.

Question 15

K+ moves through leak channels until

Answer 15

Concentration gradient out= electrical gradient back in

Question 16

Carrier protein steps

Answer 16

1 Something binds/ releases
2 This changes the carrier proteins shape
3 this changes affinity

Question 17

Membrane transports always have

Answer 17

1 Specificity
2 Competition ( maltose in GLUT transporter)
3 Saturation Transport maximum

Question 18

Pinocytosis

Answer 18

non selective form of endocytosis

Question 19

Receptor mediated endocytosis

Answer 19

Highly selective

Question 20

Lipid Raft

Answer 20

Chunk of membrane that moves together all the time

Question 21

Clathrin coated pits

Answer 21

receptors free to move around membrane

Question 22

Transcellular

Answer 22

materials pass through cells, more selective but slower and usually more ATP

Question 23

Paracellular

Answer 23

Materials pass between cells Faster with less ATP but less selective

Question 24

insulin secretion

Answer 24

1 High glucose levels in blood
2 increased metabolism creates more ATP
3 Katp channels have a low affinity for ATP so the high levels of ATP cause it to close.
4 Cell depolarizes voltage gate ion channel for Ca2+ open
5 Ca 2+ entry causes intracellular signaling resulting in exocytosis of insulin

Question 25

Insulin receptor and transduction

Answer 25

1 insulin binds to receptor
2 Phosphrylates insulin receptor and substrate
3 Second messanger activates protein synetheis and function
4 Increase number plus activity of GLUT transport protein
5 cell metabolism increased

Question 26

Hyperosmotic

Answer 26

more dissolved particles compared to something else

Question 27

isosomtic

Answer 27

equal dissloved particles compared to something else

Question 28

hyposomtic

Answer 28

less dissolved particles compared to something else

Question 29

Hypotonic

Answer 29

net loss of water

Question 30

hypertonic

Answer 30

net gain of water

Question 31

isotonic

Answer 31

gain and loss are equal