chapter 5

Question 1

fluid mosaic model

Answer 1

Diverse protein models suspended in a fluid phospholipid bilayer
The presence of cholesterol keep phospholipids from packing too tightly

Question 2

Attachment Protein

Answer 2

proteins that attach to the ECM (fibers of extracellular matrix) and cytoskeleton help support the membrane and can coordinate external and internal changes

Question 3

Receptor Protein

Answer 3

bind signaling molecules and relay the message by activating other molecules in the cell (signal transduction)

Question 4

Active Transport Protein

Answer 4

allow specific ions or molecules to enter or exit the cell

Question 5

Junction Protein

Answer 5

form intercellular junctions that attach adjacent cells

Question 6

Glycoprotein

Answer 6

serve as ID tags that are recognized by membrane proteins of other cells

Question 7

Enzymes

Answer 7

to assist reactions in the cell?

Question 8

evolution of membranes

Answer 8

Phospholipids among the first organic molecules formed

Can spontaneously self assemble into simple membranes

Question 9

purposes of cell membrane

Answer 9

encloses assembly of molecules

regulates chemical exchanges w/ environment

Question 10

what kind of energy do molecules have

Answer 10

thermal energy, because of their constant motion

Question 11

diffusion

Answer 11

particles moving from an area of high to low concentration

Question 12

passive transport

Answer 12

diffusion across a biological membrane down a concentration gradient (high to low)

Question 13

Osmosis

Answer 13

diffusion of water

Question 14

isotonic solution

Answer 14

solute concentration equal between solution and cell

Question 15

Hypotonic solution

Answer 15

solute concentration is lower than in the cell

is the water filled cell

Question 16

Hypertonic solution

Answer 16

solute concentration is higher than in the cell

is the small, shriveled cell

Question 17

osmoregulation

Answer 17

preventing excessive uptake or excessive loss of water

Question 18

plasmolysis

Answer 18

cell loses water

Question 19

facilitated diffusion

Answer 19

use of channel proteins to move substances across a membrane
(when molecules still have a net movement of a high concentration to a low concentration but they may be too large or have other characteristics that prevent them from directly traveling across the selective cell membrane, therefore they have to go through a protein channel

Question 20

active transport

Answer 20

molecules go against concentration gradient, powered by ATP

Question 21

ATPs role in active transport

Answer 21

ATP energizes transport protein

Question 22

endocytosis

Answer 22

the cell fuses with the molecules it’s taking in, in order to bring it inside, form vesicles that can be taken inside the cell

Question 23

exocytosis

Answer 23

used to get rid of cell waste and getting valuable materials out, vesicle fuses with membrane

Question 24

Phagocytosis

Answer 24

pods stretch out around what they are going to engulf, and then it pulls it in, “cell eating”

Question 25

Pinocytosis

Answer 25

allows cells to take in fluids, “cell drinking”

Question 26

Receptor-mediated endocytosis

Answer 26

incoming substances have to bind to receptors to get in

Question 27

energy

Answer 27

the capacity to cause change

Question 28

kinetic energy

Answer 28

energy of motion, ex: heat and light

Question 29

potential energy

Answer 29

Stored energy dependent upon an object’s location/structure, ex: chemical
Life depends upon the fact that E can convert into different forms

Question 30

first law of Thermodynamics

Answer 30

E can be transferred/transformed but cannot be created or destroyed

Question 31

endergonic (endothermic)

Answer 31

Requires net input of E
Products’ covalent bonds store more E than reactants
Ex: photosynthesis

Question 32

exergonic (exothermic)

Answer 32

Releases E
Reactants’ covalent bonds contain more E products
Ex: cellular respiration

Question 33

metabolism

Answer 33

Is the total amount of chemical reactions in an organism

Metabolic pathways

Question 34

Identify the role of ATP in cellular work

Answer 34

Cellular work is sustained because ATP is a renewable resource continually generated by cells - think “recycling”

Question 35

ATP

Answer 35

powers cellular work
Consists of one adenine, one ribose, and three phosphate groups
E in an ATP molecule lies in the bonds between its phosphate groups
ATP powers cellular work through couples reactions

Question 36

phosphorylation

Answer 36

the chemical addition of a phosphoryl group

Question 37

tonicity

Answer 37

the tendency of a cell in a given solution to lose or gain water

Question 38

Transport protein

Answer 38

has a pore with a hydrophilic channel for the passage of charged particles

Question 39

Carrier protein

Answer 39

large substance binds to protein, protein changes shape, release the large substance