chapter 3

Question 1

What is the first law of thermodynamics

Answer 1

It cannot be created or destroyed

Question 2

What is the second law of thermodynamics

Answer 2

Entropy is always increasing

Question 3

Why do we need to eat?

Answer 3

Organisms never reach equilibrium (ΔG = 0); life requires a constant supply of energy

Question 4

The Flow of Energy through the Biosphere. What is it?

Answer 4

Energy enters the biosphere when sunlight is converted into chemical energy by photosynthesis.

Question 5

What is Metabolism

Answer 5

Collection of all chemical reactions present within a cell or organism

Question 6

Catabolism

Answer 6

Breakdown of molecules into smaller units, releasing energy. Ex( burger breaks down into —–> Sugars, Amino acids, Fatty acids, Energy

Question 7

Anabolism

Answer 7

Building of more complex molecules/macromolecules from smaller units, requiring an input of energy. Ex.(Energy + Amino Acids=Proteins)

Question 8

ATP Hydrolysis

Answer 8

ATP hydrolysis releases free energy that can be used as a source of energy for the cell.

Question 9

Energy coupling

Answer 9

the coupling of an endergonic
reaction to an exergonic reaction

Question 10

Entropy (s)

Answer 10

measurements of random activity

Question 11

Enthalpy (h)

Answer 11

Measures the overall amount of energy

Question 12

Spontaneous reactions

Answer 12

endothermic+exothermic reactions

Question 13

Endothermic rxn

Answer 13

-Products have more total/thermal energy than reactants(in graph will drop then rise)
- Energy products> reactants
- DeltaG positive

Question 14

Exothermic rxn

Answer 14

• Energy release(graph will rise then drop)
  -Energy reactants> products
• DeltaG negative

Question 15

Photosynthesis

Answer 15

captures light energy and uses it to convert carbon dioxide into carbohydrates

Question 16

Cellular respiration

Answer 16

breaks down carbohydrates and
transforms the energy into ATP

Question 17

What are the 3 components of ATP

Answer 17

Sugar(ribose), nucleotide base, 3 phosphate groups

Question 18

Enzyme-Catalyzed Reactions

Answer 18

• Enzymes bind to a substrate
• Speeds up a reaction by binding to a substrate and helping it undergo a chemical change

Question 19

Activation Energy

Answer 19

Initial input of energy to start a
reaction, even if it is spontaneous

Question 20

Catalyst

Answer 20

Chemical agent that speeds up the rate of reaction without itself being chemically altered. EX. Enzymes

Question 21

Enzyme co-factors

Answer 21

Non-protein molecule that supports a biochemical reaction. Ex. Zinc, copper, Magnesium

Question 22

Coenzymes

Answer 22

Organic compounds that help enzymes become active and function properly. Ex. NAD+, FAD,

Question 23

Transition state

Answer 23

Intermediate state of the reaction, when the molecule is neither a substrate or product

Question 24

3 Major mechanisms of transition state

Answer 24

1. Bringing the reacting molecules into close proximity
2. Placing reactant molecules in environments that enhance their interactions.
3. Changing the shape of a substrate molecule

Question 25

When substrate concentration is low.....

Answer 25

- Enzymes and substrates rarely collide - Reaction rate slows

Question 26

When substrate concentration is high....

Answer 26

It increases the rate of reaction and results in rate of reaction levels off

Question 27

Competitive inhibition

Answer 27

Inhibitor competes with normal substrate for active site

Question 28

Noncompetitive inhibition

Answer 28

Inhibitor does not compete with normal substrate for active site, but combines with sites elsewhere on enzyme Inhibitor

Question 29

Allosteric regulation

Answer 29

a widespread mechanism of control of protein function

Question 30

Feedback inhibition

Answer 30

A product that controls the reaction

Question 31

Effects of Temperature

Answer 31

As temperature rises, the rate of reactions increases