Ch 11 - Membrane Structure

Question 1

amphipathic

Answer 1

having both hydrophobic and hydrophilic regions, as in a phospholipid or a detergent molecule

Question 2

bacteriorhodopsin

Answer 2

pigmented protein found in abundance in the plasma membrane of the salt-loving archaeon Halobacterium halobium; pumps protons out of the cell, fueled by light energy

Question 3

cell cortex

Answer 3

specialized layer of cytoplasm on the inner face of the plasma membrane. in animal cells, it is rich in actin filaments that govern cell shape and drive cell movement

Question 4

cholesterol

Answer 4

short, rigid lipid molecule present in large amounts in the plasma membranes of animal cells, where it makes the lipid bilayer less flexible

Question 5

detergent

Answer 5

soapy substance used to solubilize lipids and membrane proteins

Question 6

fat droplet

Answer 6

large cluster of hydrophobic fats or oils that forms inside the cells

Question 7

glycocalyx

Answer 7

protective layer of carbohydrates on the outer surface of the plasma membrane formed by the sugar residues of membrane glycoproteins, proteoglycans and glycolipids

Question 8

lipid bilayer

Answer 8

thin pair of closely juxtaposed sheets, composed mainly of phospholipid molecules, that forms the structural basis for all cell membranes

Question 9

membrane domain

Answer 9

functionally and structurally specialized region in the membrane of a cell or organelle; typically characterized by the presence of specific proteins

Question 10

membrane protein

Answer 10

a protein associated with the lipid bilayer of a cell membrane

Question 11

phosphatidylcholine

Answer 11

common phospholipid present in abundance in most cell membranes; uses choline attached to a phosphate as its head group

Question 12

phospholipid

Answer 12

a major type of lipid molecule in many cell membranes. generally composed of two fatty acid tails linked to one of a variety of phosphate-containing polar groups

Question 13

plasma membrane

Answer 13

the protein-containing lipid bilayer that surrounds a living cell

Question 14

saturated

Answer 14

describes an organic molecule that contains a full complement of hydrogen; in other words, no double or triple carbon-carbon bonds

Question 15

unsaturated

Answer 15

describes an organic molecule that contains one or more double or triple bonds between its carbon atoms