Energy Transformations (class 24)

Question 1

1st Law of Thermodynamics

Answer 1

Energy is neither created nor destroyed

Question 2

2nd Law of Thermodynamics

Answer 2

After an energy transformation, usable energy will be less than original amount.

Energy transformations result in an increase in entropy.

Question 3

Phosphotrophs

Answer 3

Organisms that capture energy from sunlight

Question 4

Chemotrophs

Answer 4

Organisms that derive energy from chemical compounds

Question 5

Heterotrophs

Answer 5

Organisms that obtain their carbon from organic molecules synthesized by other organisms

Question 6

Metabolism

Answer 6

The set of chemical reactions that sustain life

Question 7

Catabolism

Answer 7

Chemical reactions that break down molecules, producing ATP

Question 8

Anabolism

Answer 8

Chem. reactions that build molecules requiring ATP

Question 9

Example of potential energy

Answer 9

Electrochemical gradient

Question 10

Chemical energy is a form of…

Answer 10

Potential energy.

Question 11

ATP is made up of…

Answer 11

Base adenine, ribose, triphosphate

Question 12

Where is the chemical energy of ATP stored?

Answer 12

Within the bonds connecting the phosphate groups.

Question 13

Chemical equilibrium

Answer 13

Rates of forward and reverse reactions are equal, reactant and product concentrations are constant.

Question 14

DeltaG

Answer 14

Negative: Exothermic
Positive: Endothermic

Equals the energy difference between the reactants and products.

Question 15

Exergonic

Answer 15

Exothermic

Question 16

Endergonic

Answer 16

Endothermic

Question 17

Spontaneous

Answer 17

Releases energy

Question 18

Is the hydrolysis of ATP exergonic or endergonic?

Answer 18

Exergonic

Question 19

Energetic coupling

Answer 19

Spontaneous rxn drives nonspontaneous rxn. The neg DeltaG must be negative. Often, an intermediate is shared.

Question 20

Potential energy

Answer 20

Stored: chemical bonds, concentration gradient

Question 21

Kinetic energy

Answer 21

Working energy: light, heat

Question 22

How do enzymes act as catalysts?

Answer 22

1. Orientation so bonds are favorable
2. Physical strain: bonds want to break

Question 23

What provides energy for endergonic reactions?

Answer 23

ATP

Question 24

High energy bonds

Answer 24

Release more energy, require more energy to make, require little energy to break

Question 25

Reduction:

Answer 25

Reduction is gaining electrons (losing bonds to oxygen)

Question 26

Oxidation

Answer 26

Oxidation is losing electrons (gaining bonds to oxygen)