Chap. 7 (Vocab.)

Question 1

Amphipathic

Answer 1

Having both a hydrophilic and hydrophobic region

Question 2

Integral Protein

Answer 2

1. Proteinfully or partially permanently embedded in cell membrane
2. Amphipathic
3. Interacts with hydrophobic. phospholipid parts with its hydrophobic interior of amino acids

Question 3

Transmembrane Protein

Answer 3

Type of integral protein that is fully embedded in cell membrane

Question 4

Peripheral Protein

Answer 4

Proteins loosely associated with cell surface, not embedded in it

Question 5

Cell-cell Recognition

Answer 5

1. Cell’s ability to distinguish one neighboring cell from another
2. Due to carbohydrates

Question 6

Glycolipid

Answer 6

Lipid with carbohydrate covalently attached to it

Question 7

Glycoproteins

Answer 7

Protein with carbohydrate covalently attached to it

Question 8

Selective Permeability

Answer 8

Property that allows membrane to regulate material flow

Question 9

Transport Protein

Answer 9

Transmembrane protein that helps substances cross the membrane

Question 10

Channel Proteins

Answer 10

Hydrophilic channel that certain molecules/ions use as a tunnel through the membrane

Question 11

Aquaporin

Answer 11

Channel proteins that allows water to pass through membrane

Question 12

Carrier Proteins

Answer 12

Transport protein that binds to molecules and change shape to shuttle them across membrane

Question 13

Diffusion

Answer 13

Molecules move from a high to low concentration area without the need of assistance of proteins

Question 14

Dynamic Equilibrium

Answer 14

As many molecules cross the membrane in one direction as in the other

Question 15

Concentration Gradient

Answer 15

Difference in concentration of a substance between two areas (passive transport)

Question 16

Passive Transport

Answer 16

DIffusion across membrane where no energy is required

Question 17

Osmosis

Answer 17

Water molecules pass through semipermeable membrane from more concentrated area to less concentrated area until it is equal on both sides

Question 18

Tonicity

Answer 18

1. Ability of a solution to change the volume of a cell by affecting the cell’s water content
2. Depends on concentration of solutes that cannot pass membrane relative to that inside the cells

Question 19

Isotonic

Answer 19

Solute concentration is the same as that of inside the cell; no net water movement

Question 20

Hypotonic

Answer 20

Solute concentration is greater than that inside the cell; cell loses water

Question 21

Hypertonic

Answer 21

Solute concentration is less than that inside the cell; cell gains water

Question 22

Turgid

Answer 22

Swollen cell due to fluids

Question 23

Flaccid

Answer 23

Soft cell

Question 24

Plasmolysis

Answer 24

Plant cell loses water to its surrounding environment, causing the cytoplasm and plasma membrane to shrink away from the cell wall

Question 25

Facilitated DIffusion

Answer 25

Larger molecules cross membrane w/o energy input using transport proteins

Question 26

Ion Channels

Answer 26

Proteins that allow electrically charged particles, or ions, to pass through cell membranes

Question 27

Gated Channels

Answer 27

Ion channel that opens or closes based on response from stimuli

Question 28

Active Transport

Answer 28

Requires energy, usually in ATP hydrolysis, to move substances against concentration of gradient (carrier proteins)

Question 29

Sodium-potassium Pump

Answer 29

Transport protein in plasma membrane of animal cells that actively transports sodium out of the cell and potassium into the cell

Question 30

Membrane Potential

Answer 30

Voltage across a membrane

Question 31

Electrochemical Gradient

Answer 31

Diffusion of ions across membrane, due to: 1. Chemical Force 2. Electrical Force

Question 32

Electrogenic Pump

Answer 32

Transport protein that generates voltage across membrane

Question 33

Proton Pump

Answer 33

1. Electrogenic pump for fungi, plant, and bacteria cells 2. Activey transports hydrogen ions out of cell

Question 34

Cotransport

Answer 34

1. Activey transporting two substances across a cell membrane at the same time 2. Uses one substances movement to power the other

Question 35

Exocytosis

Answer 35

Transport vesicles migrate to the membrane, fuse with it, and release their contents outside the cell

Question 36

Endocytosis

Answer 36

Cell takes in macromolecules by forming vesicles from the plasma membrane

Question 37

Phagocytosis

Answer 37

1. Cell engulfs a particle in a vacuole 2. The vacuole fuses with a lysosome to digest the particle

Question 38

Pinocytosis

Answer 38

Cell ingests extracellular fluid + its dissolved fluids

Question 39

Receptor-Mediator Endocytosis

Answer 39

Cells selectively absorb specific molecules from their environment trhough receptor proteins

Question 40

Chemical Force

Answer 40

Ion concentration gradient

Question 41

Electrical Force

Answer 41

Effect on membrane potential on ion's movements