Cell membrane

Question 1

All cells are surrounded by a

Answer 1

cell surface/plasma membrane

Question 2

cell membrane appears under electron microscope as

Answer 2

double lined

Question 3

the usual distance across a cell membrane is

Answer 3

7-8 nanometres

Question 4

the cell membrane is made up of mostly

Answer 4

proteins and lipids

Question 5

cell membrane proteins

Answer 5

simple proteins
glycoproteins
lipoproteins(carry cholesterol)

Question 6

cell membrane lipids

Answer 6

phospholipids
glycolipids
cholesterol

Question 7

phospholipids have a

Answer 7

polar hydrophilic phosphate head
fatty acid nonpolar hydrophobic tail

Question 8

phospholipids form a

Answer 8

bilayer with tails pointing to eachother

Question 9

phospholipid bilayer function

Answer 9

lets lipid soluble molecules across

Question 10

two types of cell membrane proteins

Answer 10

extrinsic
intrinsic

Question 11

extrinsic proteins

Answer 11

attached to the exterior of the membrane
function: structural support, forming recognition and receptor sites for hormones

Question 12

intrinsic proteins

Answer 12

extends across both layers
functions: includes transport proteins which move molecules/ions across actively or passively

Question 13

channel proteins

Answer 13

hydrophilic r groups of amino acids,used in facilitative diffusion

Question 14

glycocalyx

Answer 14

carb layer around an animal cell after the proteins are glycosylated(bonded with carb chain)

Question 15

glycolipid

Answer 15

membrane stability
cell recognition

Question 16

glycoprotein

Answer 16

recognition of self/nonself cells
receptors

Question 17

cholesterol

Answer 17

make the membrane more stable at higher temps and more fluid at low temperatures

Question 18

why is it called fluid mosaic model

Answer 18

the phospholipid molecules move within a layer-fluid
protein vary in shape + size-mosaic

Question 19

roles of cell plasma membrane

Answer 19

-separate cell contents from outside
-regulates transport of ions in and out of cells
-hormonal receptor sites
-recognition with antigens that can produce immune responses

Question 20

roles of internal membranes

Answer 20

-separates cell components from cytoplasm EG nuclear pores with mrna and ribosomes
-hold metabolic component pathways in place EG ribosomes attached to RER
-chemical reactions
EG aerobic respiration in inner mitochondrial membrane
photosynthesis in grana

Question 21

permeability

Answer 21

small molecules move between phospholipids and diffuse
lipid soluble substances dissolve and diffuse easier

Question 22

water soluble substances pass through

Answer 22

intrinsic proteins which form water channels