Ch 7 Exam 2

Question 1

What is energy?

Answer 1

the capacity to do work (change in state or motion of matter)

Question 2

What is kinetic energy?

Answer 2

the energy of
motion

Question 3

What is potential energy?

Answer 3

the capacity to do work as a result of position or state

Question 4

What is chemical energy?

Answer 4

stored in chemical bonds (ATP)

Question 5

What is electrical energy?

Answer 5

Results from movement of charged particles

Question 6

What is mechanical energy?

Answer 6

directly involved in moving matter

Question 7

What is radiant (electromagnetic) energy?

Answer 7

travels in waves (light energy)

Question 8

What is thermodynamics?

Answer 8

the study of energy and its transformations

Question 9

What is an open system?

Answer 9

can exchange energy with its surroundings

Question 10

What is a closed system?

Answer 10

does not exchange
energy with its surroundings

Question 11

Are living organisms open or closed systems?

Answer 11

open

Question 12

What is the 1st Law of Thermodynamics?

Answer 12

energy is neither created nor destroyed

Question 13

What is the 2nd Law of Thermodynamics?

Answer 13

When energy is converted from one form to another, some usable energy is converted into HEAT

Question 14

What is entropy?

Answer 14

disorder/randomness is increasing

Question 15

What is the ultimate source of energy for all life on this planet?

Answer 15

the sun

Question 16

What is free energy?

Answer 16

the amount of energy available to do work

Question 17

What is metabolism?

Answer 17

all chemical reactions taking place in an organism

Question 18

What is anabolism?

Answer 18

builds large molecules from smaller ones, (uses energy)

Question 18

What is catabolism?

Answer 18

breaks large molecules into smaller molecules, (releases energy)

Question 19

What are reactants and products?

Answer 19

reactants: substances that participate
products: substances that form

Question 20

What is activation energy?

Answer 20

energy required to drive a chemical reaction

Question 21

What is an endergonic reaction? Example?

Answer 21

Products have MORE free energy than reactants

EX. DEHYDRATION SYNTHESIS

Question 22

What is an exergonic reaction? Example?

Answer 22

Reactants have more free energy than products

ex. Hydrolysis

Question 23

What is a coupled reaction?

Answer 23

exergonic reaction provides the energy to drive endergonic reaction

Question 24

What is a metabolic pathway?

Answer 24

a series of reactions

Question 25

What are enzymes and how do they work?

Answer 25

Increase speed of a chemical reaction without being consumed by the reaction

Question 26

How does an enzyme work?

Answer 26

Enzymes bind with a substrate

Question 27

How do you identify an enzyme by its name?

Answer 27

adding a suffix “-ase”

Question 28

What is an apoenzyme and a cofactor?

Answer 28

- an apoenzyme (protein portion) -Cofactor – metal ion (ex. Iron, cooper, zinc)

Question 29

In two-part enzymes, what is the whole enzyme called?

Answer 29

Coenzyme

Question 30

What is the binding site where substrates attach to an enzyme?

Answer 30

active sites

Question 31

What are reactants called that interact with an enzyme?

Answer 31

substrate

Question 32

What is the complex called when the substrate is bound to the enzyme?

Answer 32

Induced fit

Question 33

What can affect the rate of an enzyme catalyzed reaction? (3)

Answer 33

temperature pH Concentration of substrate

Question 34

What does reversible inhibition mean?

Answer 34

forms weak chemical bonds with the enzyme (can be competitive or noncompetitive)

Question 35

What is competitive inhibition?

Answer 35

the inhibitor competes with the normal substrate for binding to the active site

Question 36

What is an allosteric site?

Answer 36

modifies the enzyme’s activity when an allosteric regulator is bound to it

Question 36

What is non-competitive inhibition?

Answer 36

binds at a site other than the active site

Question 37

What is irreversible inhibition?

Answer 37

permanently inactivates or destroys an enzyme when the inhibitor combines with one of the enzyme’s functional groups

Question 38

What is ATP? What are the three parts of an ATP molecule?

Answer 38

Adenosine triphosphate (ATP): Nucleotide consisting of adenine, ribose, and three phosphate groups

Question 39

What happens when an enzyme is denatured?

Answer 39

lose its ability to catalyze a chemical reaction

Question 40

What are the functions of ATP?

Answer 40

The cell uses energy that is temporarily stored in ATP

Question 41

What is oxidation and reduction?

Answer 41

-Oxidation: substance loses electrons -Reduction: substance gains electrons