Lecture 3 Energy and Enzymes

Question 1

Forms of Energy

Answer 1

1. Potential

2. Kinetic

Question 2

Potential Energy

Answer 2

-Energy of position (stored Energy)

Ex.Chemical energy (in bonds)

Question 3

kinetic Energy

Answer 3

-energy of motion

Ex. mechanicle Energy

Question 4

Metabolism

Answer 4

-Sum of all chemical reactions in a living organism
include:
1.anabolism
2.catabolism

Question 5

Anabolism

Answer 5

• Biosynthesis reaction:building

- Endergonoc:require energy

Question 6

Catabolism

Answer 6

• Degradative reactions:Breaking down

- Exergonic:release energy

Question 7

Chemical reactions

Answer 7

Components
-substrate:what goes in(reactant)
-product:what comes out
Directions 
-foward
-Reverse

Question 8

Factors affecting chemical reactions

Answer 8

1.law of mass action
2activation Energy
3.Enzymes

Question 9

Law of Mass Action

Answer 9

• Foward Reactions
• increase reactants you increase products
• If you increase the product you will slow down production of the product

Question 10

Reversible Reactions

Answer 10

increase reactant or decrease product it will move to the right
Decrease reactant or increase product it will move to the left

Question 11

Activation Energy

Answer 11

-Minimum Energy required for reactants to overcome activation energy barrier to transition state tp product

Question 12

Enzymez

Answer 12

Structure:-protien based molecules
-substrate specific
Function:Reduce activation Energy
-Biological catalysts;

Question 13

-Biological catalysts

Answer 13

• speeds up reactions

- does not get used up or changed

Question 14

Models for Enzyme binding

Answer 14

1. lock and key mechanism

2. induced fit model

Question 15

Lock and Key Mechanism

Answer 15

• Substrate fit enzyme like a key to a lock

- problem:dosnt explain reversible reactions

Question 16

Induced Fit model

Answer 16

• substrate approximately fit enzyme

- After binding -> conformation change for better fit

Question 17

How Enzymes work

Answer 17

Enzymes bind with a substrate , converting the to products

Question 18

Enzyme Sites

Answer 18

1. Active site:where substrate binds

2. Allosteric site:where other molecules (other than substrate) attch

Question 19

Types of Enzymes

Answer 19

1. Simple Enzymes;protiens with catalytic activity

2. Holoenzymes:conjugated enzymes

Question 20

Holoenzyme Components

Answer 20

1.protien portion:Apoenzyme
2.Non-protien portion
-cofactor;inorganic ions
Ex.Iron,Zinc,Magnisum,Calcium
-coenzyme:Organic molecules(vitamine derivatiives)
Ex.NAD+, NADP+,FAD,coenzyme A

Question 21

Factors influencing Enzymatic rates

Answer 21

1. Enzyme catalytic rate
2. substrate concentration
3. Enzyme concentration
4. Affinity
5. Temperatur
6. pH

Question 22

Enzymes catalytic rate

Answer 22

Inherent speed of the enzyme

Question 23

Substrate concentration

Answer 23

increasing substrate, increases activity until saturation

Question 24

Saturation

Answer 24

Enzyme active site filled wit Substrate

Question 25

Enzyme Concentration

Answer 25

Increase in enzyme= increase in maximum rate

Question 26

Affinity

Answer 26

- How tightly a substrate binds to the active site | - High affening, increases reaction rates

Question 27

Temperature

Answer 27

Enzymes have an Optimal temperature - increase rate of collision and reactions - to much heat will cause enzyme to denature(breaking of bonds)

Question 28

pH

Answer 28

Enzymes have an Optimal ph | -Entreme pH will cause the Enzyme to denature

Question 29

Enzyme Regulation

Answer 29

1. Allosteric Regulation | 2. Inhibitors

Question 30

Allosteric Regulation

Answer 30

- modulater(weakly)bind to allosteric site 1. Activatior:increase catalytic rate - increase affinity to substrate 2. Inhibitor-Decrease Enzymatic Activity

Question 31

Inhibitors

Answer 31

1.competitive;chemical that bind to active site Ex.Penicilin,sulfanilamide 2.Non-competitive:chemicals that bind to allosteric site or cofactors Ex.enzyme poisons(cyanine, Fluoride)