biological membranes part 1

Question 1

fluid

Answer 1

-no fixed shape
-yields easily to outside pressure
-flows easily

Question 2

mosaic

Answer 2

a picture or pattern composed of many different pieces

Question 3

integral

Answer 3

membrane proteins are embedded in the membrane, in the phospholipid bilayer; some cross the entire bilayer, others only partially embedded; have both hydrophilic and hydrophobic domains

Question 4

peripheral

Answer 4

proteins that do not penetrate the bilayer; loosely attached; hydrophobic, ionic, and other non-covalent interactions

Question 5

anchored

Answer 5

-proteins are covalently bonded to lipids in the membrane
-are covalently attached to fatty acids or other lipids in the membrane

Question 6

transmembrane proteins

Answer 6

extend through to both sides

Question 7

glycolipids and glycoproteins

Answer 7

extend out from the cell surface

Question 8

cell recognition and cell adhesion

Answer 8

depend on surface proteins and carbohydrates

Question 9

homotypic

Answer 9

the same molecule sticks out from both cells and bind to each other

Question 10

heterotypic

Answer 10

the cells have different proteins that bind together

Question 11

cell junctions

Answer 11

are specialized that hold cells together

Question 12

tight juctions

Answer 12

help ensure directional movement of materials
ex: the bladder

Question 13

desosomes

Answer 13

“spot welds”; provide mechanical stability
ex: skin

Question 14

gap junctions

Answer 14

allow communication
ex: the heart