ch5

Question 1

exocytosis

Answer 1

process of passing bulk material out of a cell

Question 2

diffusion

Answer 2

passive process of transport of low-molecular weight material according to its concentration gradient

Question 3

facilitated transport

Answer 3

process by which material moves down a concentration gradient (from high to low concentration) using integral membrane proteins

Question 4

channel protein

Answer 4

membrane protein that allows a substance to pass through its hollow core across the plasma membrane

Question 5

concentration gradient

Answer 5

area of high concentration adjacent to an area of low concentration

Question 6

selective permeability

Answer 6

characteristic of a membrane that allows some substances through but not others

Question 7

osmosis

Answer 7

transport of water through a semipermeable membrane according to the concentration gradient of water across the membrane that results from the presence of solute that cannot pass through the membrane

Question 8

passive transport

Answer 8

method of transporting material through a membrane that does not require energy

Question 9

electrochemical gradient

Answer 9

gradient produced by the combined forces of an electrical gradient and a chemical gradient

Question 10

active transport

Answer 10

method of transporting material that requires energy

Question 11

hydrophilic

Answer 11

molecule with the ability to bond with water; “water-loving”

Question 12

fluid mosaic model

Answer 12

describes the structure of the plasma membrane as a mosaic of components including phospholipids, cholesterol, proteins, glycoproteins, and glycolipids, resulting in a fluid character

Question 13

hydrophobic

Answer 13

molecule that does not have the ability to bond with water; “water-hating”

Question 14

hypotonic

Answer 14

situation in which extracellular fluid has a lower osmolarity than the fluid inside the cell, resulting in water moving into the cell

Question 15

isotonic

Answer 15

situation in which the extracellular fluid has the same osmolarity as the fluid inside the cell, resulting in no net movement into or out of the cell

Question 16

hypertonic

Answer 16

situation in which extracellular fluid has a higher osmolarity than the fluid inside the cell, resulting in water moving out the cell

Question 17

carrier protein

Answer 17

membrane protein that moves a substance across the plasma membrane by changing its own shape

Question 18

clathrin

Answer 18

protein that coats the inward-facing surface of the plasma membrane and assists in the formation of specialized structures, like coated pits, for phagocytosis

Question 19

endocytosis

Answer 19

type of active transport that moves substances, including fluids and particles, into a cell

Question 20

solute

Answer 20

substance dissolved in a liquid to form a solution