AP Bio Chap. 5

Question 1

Fluid Mosaic Model

Answer 1

Describes the organization of cell membranes.

Question 2

Enzymes

Answer 2

Accelerate reactions without being changed by them.

Question 3

Adhesion Proteins

Answer 3

Fasten cells to other cells and to ECM in animal tissues.

Question 4

Recognition Proteins

Answer 4

Function as unique identity tags for each individual or species.

Question 5

Receptor Proteins

Answer 5

Bind to a particular substance outside of the cell, such as a hormone.

Question 6

Transport Proteins (transporters)

Answer 6

Integral membrane proteins that move specific ions or molecules across a lipid bilayer.

Question 7

Selective Permeability

Answer 7

The ability of a cell to maintain these differences depends on a property of membranes.

Question 8

Concentration

Answer 8

Number of molecules (or ions) of a substance per unit volume of fluid.

Question 9

Concentration Gradient

Answer 9

A difference in concentration between two adjacent regions.

Question 10

Diffusion

Answer 10

Overall movement of molecules or ions down a concentration gradient.

Question 11

Passive Transport

Answer 11

A concentration gradient drives the diffusion of a solute across a cell membrane, with the assistance of a transport protein.

Question 12

Active Transport

Answer 12

A transport protein uses energy to pump a solute against its gradient across a cell membrane.

Question 13

Calcium Pumps

Answer 13

Active transporters that move calcium ions across muscle cell membranes.

Question 14

Cotransporter

Answer 14

Moves two substances at the same time.

Question 15

Exocytosis

Answer 15

Vesicle moves to the cell surface, and the protein-studded lipid bilayer of its membrane fuses with the plasma membrane. As the vesicle loses its identity, its contents are released to the surroundings.

Question 16

Endocytosis

Answer 16

Take up substances near the cell’s surface.

Question 17

Phagocytosis

Answer 17

Endocytic pathway.

Question 18

Osmosis

Answer 18

Water molecules tend to diffuse in response to their own concentration gradient.

Question 19

Hypotonic

Answer 19

When the solute concentrations differ, the fluid with the lower concentration of solutes.

Question 20

Hypertonic

Answer 20

When the solute concentrations differ, the fluid with the higher concentration solutes.

Question 21

Hydrostatic Pressure (Turgor)

Answer 21

Pressure that a volume of fluid exerts against a cell wall, membrane, tube or any other structure that holds it.

Question 22

Osmotic Pressure

Answer 22

The amount of hydrostatic pressure that can stop water from diffusing into cytoplasmic fluid or other hypertonic solution.

Question 23

Phospholipid Bilayer

Answer 23

Cell membrane made of two layers of molecules with a phosphate-containing head and two fatty acid tails.

Question 24

Integral

Answer 24

Permanently Attached

Question 25

Peripheral

Answer 25

Temporarily Attach to one of bilayer’s surfaces.

Question 26

Isotonic

Answer 26

When the solute concentrations are the same.

Question 27

___________ diffuse faster

Answer 27

Smaller.

Question 28

Molecules move faster at a __________ temperature, more collisions/rebounds

Answer 28

Temperature.

Question 29

Rate of Diffusion Depends on…

Answer 29

Size, Temperature, Steepness, Charge, Pressure.

Question 30

Charge

Answer 30

Opposites attract; like charges repel.

Question 31

__________ pressure squeezes molecules together

Answer 31

Increased.