B2.1

Question 1

what macromolecules are in membranes

Answer 1

proteins
lipids
small carbs

Question 2

what are the major classes of lipids

Answer 2

phospholipids
glycolipids
sterols

Question 3

describe what a phospholipid looks like

Answer 3

modified glycerol molecule with a neg charged phosphate group and two fatty acid chains

Question 4

describe phospholipids in an aqueous environment

Answer 4

tails point inward

Question 5

where is cholesterol located

Answer 5

between tails

Question 6

term for water loving and hating

Answer 6

amphipathic

Question 7

what can pass through the membrane

Answer 7

steroids
lipid soluble
small uncharged (h20, o2)

Question 8

what is permability reliant on

Answer 8

hydrophobic/hydrophilic nature

Question 9

what is simple diffusion + example

Answer 9

the passive transport of molecules from high to low concentration
diffusion of oxygen from high to low concentration in red blood cells

Question 10

what is a transmembrane protein

Answer 10

a protein that extends fully across a membrane (integral)

Question 11

explain the polarity of integral proteins

Answer 11

top/outer part is hydrophilic and interacts with the heads, while the inner part is hydrophobic and interacts with the tails

Question 12

explain the polarity of peripheral proteins

Answer 12

hydrophilic and interacts with the heads

Question 13

4 functions of membrane proteins

Answer 13

cell - cell recognition
transport
receptors
enzymes

Question 14

function of transport proteins + 2 types

Answer 14

facilitate movement
channel proteins
- form channels for movement
carrier proteins
- conformational change

Question 15

function of recognition proteins

Answer 15

distinguish between self and non self cells with cell - cell recognition

Question 16

function of receptor proteins

Answer 16

binding of molecules to this protein can facilitate reactions or processes

Question 17

function of enzyme proteins

Answer 17

catalyze reactions

Question 18

what are aquaporins

Answer 18

integral proteins that speed up the movement of water down a concentration gradient

Question 19

Facilitated diffusion

Answer 19

movement of solutes down a concentration gradient monitored by size and polarity
movement is mediated by size and polarity
aided by channel and carrier proteins

Question 20

what type of protein is used for ion pumps

Answer 20

channel proteins

Question 21

what decides the ion used for the channel protein

Answer 21

binding sites being highly specific

Question 22

what forms of stimuli can open/close

Answer 22

changes in voltage
binding of molecules (ligand gated)

Question 23

how do carrier proteins transfer molecules

Answer 23

undergo conformational change and binds to the solute

Question 24

what is active transport used for

Answer 24

transporting nutrients against a concentration gradient
remove waste
maintain concentrations

Question 25

two types of active transport

Answer 25

direct –> regular, uses atp
indirect –> movement of one down its gradient makes another against its gradient

Question 26

two classes of recognition proteins

Answer 26

gated ion channels
specific carrier proteins (GLUT)

Question 27

types of glycolipids

Answer 27

glycoglycerolipids –> based on glycerol molecules
glycophingolipids –> derivatives of sphingosine

Question 28

how do glycolipids contribute to membrane stability

Answer 28

forms h bonds with mobile water

Question 29

functions of glycolipids and glycoproteins

Answer 29

cell - cell recognition
cell adhesion
cell signalling

Question 30

what is glycocalyx

Answer 30

sticky layer formed by surface of glycolipids and glycoproteins

Question 31

what contributes to the fluid mosaic model

Answer 31

lipids and proteins can move freely in the membrane