Ch 3

Question 1

Potential energy

Answer 1

Stored energy

Question 2

Kinetic energy

Answer 2

Energy of motion

Question 3

Chemical energy

Answer 3

Form of potential energy

Most important in body

Used for:

Movement
Molecule synthesis
Establishing concentration gradients

Question 4

Thermodynamics

Answer 4

Study of energy transformations

Can be changed in forms

Question 5

First law of thermodynamics

Answer 5

Energy can neither be created nor destroyed, it can only change form

Question 6

Second law of thermodynamics

Answer 6

When energy is transformed, some energy is lost as heat

Usable energy decreases

Question 7

Metabolism

Answer 7

All biochemical reactions in living organisms

Question 8

Chemical reactions

Answer 8

Occur when chemical bonds in existing molecular structure are broken

Question 9

Decomposition reaction

Answer 9

Initial large molecule is broken down into smaller structures

Aka catabolism

Question 10

Synthesis reaction

Answer 10

Two or more structures combined to form a larger structure

Aka anabolism

Question 11

Exergonic reaction

Answer 11

Reactants have more potential energy within their chemical bonds than the products

Energy is released

Question 12

Endergonic reaction

Answer 12

Reactants have less potential energy

Energy must be “put in”

Question 13

Activation energy

Answer 13

Energy required to break existing chemical bonds

Determines reaction rate

Question 14

Enzymes

Answer 14

Catalysts that accelerate normal physiologic activities

Decrease activation energy of cellular reactions

Increase rate of product formation

Question 15

Location of enzymes

Answer 15

Within cells

Plasma membrane

Some secreted from cell

Question 16

Enzyme catalysis

Answer 16

1. Substrate enters active site, forming enzyme substrate complex
2. Enzyme changes the shape slightly (induced fit model)
3. Change in enzyme shape stresses chemical bonds, permitting new bonds to be formed
4. Products are released; enzyme may repeat process (glucose and galactose released)

Question 17

Cofactors

Answer 17

Molecules or “helper” ions required to ensure that a reaction occurs

Associated with particular enzyme

Non protein organic and inorganic structure

Question 18

Reaction rate

Answer 18

Increase in enzyme concentration

Increase in substrate concentration

3D shape

pH 6-8

Question 19

Saturation

Answer 19

So much substrate is present that all enzyme molecules are engaged in reaction

Question 20

Inhibitor

Answer 20

Bind enzymes and prevent enzymatic catalysis

Prevent overproduction of product

Release of inhibitor allows it to function and catalysis continues

Question 21

Competitive inhibitor

Answer 21

Binds to active site

Completes for occupation

Question 22

Non competitive inhibitor

Answer 22

Do not resemble substrate

Bind to site other than active site (allosteric site)

Aka allosteric inhibitors

Question 23

Cellular respiration

Answer 23

Multistep metabolic pathway where organic molecules are broken down in a controlled manner by a series of enzymes

Potential energy released

Energy used to make ATP

Oxygen required

Focus on glucose

Question 24

Four stages of glucose oxidation

Answer 24

Glycolysis (cytosol)

Mitochondria:

Intermediate stage

Citric acid cycle

Electron transport chain

Question 25

Glycolysis

Answer 25

Does not require oxygen

Occurs in cytosol

Glucose to pyruvate

Question 26

Intermediate stage of glycolysis

Answer 26

Pyruvate converted to acetyl CoA

Occurs in mitochondria

Question 27

Citric acid cycle

Answer 27

Requires oxygen

9 enzymes in matrix

Acetyl CoA to TWO CO2

CoA released

ATP, 3 NADH, and 1 FADH2 formed

Breakdown of glucose complete

Question 28

Enzyme action order

Answer 28

Formation of enzyme-substrate complex

Induced fit

Formation or breakage of chemical bonds

Release of product

Question 29

Electron transport chain

Answer 29

Requires oxygen

Involves proteins in the cristae of the mitochondria

Question 30

Process of glycolysis involves

Answer 30

Ten enzymes break glucose down to two pyruvate molecules