the structure of cell membranes

Question 1

what is the fluid mosaic model

Answer 1

the theory of cell membrane structure with proteins embedded in a sea of phospholipids

Question 2

what is a glycolipid

Answer 2

lipid/phospholipid with a chain of carbohydrate molecules attached

Question 3

what is a glycoprotein?

Answer 3

protein with a chain of carbohydrate molecules attached

Question 4

different ways of diffusing through the plasma membrane

Answer 4

very small molecules can pass straight through
some dissolve in lipid layer the pass through
some pass through protein channels or are carried by carrier proteins

Question 5

roles of cell surface membrane

Answer 5

regulates transport of materials
may contain enzymes involved in specific metabolic pathways
has antigens so the organisms immune system can recognise the cell
may release chemicals
contains receptors
may be site of chemical reactions

Question 6

what could the proteins on the membrane be

Answer 6

carrier proteins enzymes, antigens or receptors

Question 7

what are the affects of cholesterol?

Answer 7

regulates membrane fluidity and resist effects of temperature change on the membrane

Question 8

what is the thickness of a cell membrane

Answer 8

between 5 and 10 nm

Question 9

examples of specialisation on cell membranes

Answer 9

neurones have a myelin sheath formed by flattened cells

the membranes of white blood cells contain receptors that can recognise the antigens of foreign cells