biological membranes part 3

Question 1

active transport

Answer 1

moves substances against a concentration and/or electrical gradient; requires energy; the energy source is often adenosine triphosphate; low concentration to high concentration

Question 2

uniporter

Answer 2

moves one substance in one direction

Question 3

symporter

Answer 3

move two substances in one direction

Question 4

antiporter

Answer 4

moves two substances in opposite directions

Question 5

primary active transport

Answer 5

requires direct hydrolysis of ATP

Question 6

secondary active transport

Answer 6

energy comes from an ion concentration gradient that is established by primary active transport

Question 7

sodium-potassium (Na+–K+) pump

Answer 7

an integral membrane glycoprotein (an antiporter)

Question 8

macromolecules

Answer 8

proteins, polysaccharides, nucleic acids

Question 9

endocytosis

Answer 9

brings molecules and cells into a eukaryotic cell

Question 10

phagocytosis

Answer 10

cellular “eating” of large particles or cells; molecules or entire cells are engulfed

Question 11

pinocytosis

Answer 11

cellular “drinking” of fluids and particles: a vesicle forms to bring small dissolved substances or fluids into a cell

Question 12

receptor-mediated endocytosis

Answer 12

specific molecules

Question 13

receptor proteins

Answer 13

integral membrane proteins located at specific sites on the cell membrane

Question 14

exocytosis

Answer 14

materials packaged in vesicles are secreted from a cell when the vesicle membrane fuses with the cell membrane