Energy And Enzymes

Question 1

What is bioenergetics?

Answer 1

The study of energy flow through biological systems

Bioenergetics explores how energy is transformed and utilized in living organisms.

Question 2

What is metabolism?

Answer 2

Enzymatically-driven processes

Metabolism encompasses all chemical reactions in living organisms that maintain life.

Question 3

What are the two main types of metabolism?

Answer 3

• Anabolism
• Catabolism

Anabolism involves building complex molecules, while catabolism involves breaking down molecules for energy.

Question 4

Define anabolism.

Answer 4

Building complex molecules (e.g., photosynthesis, lipid synthesis)

Anabolism is crucial for growth and repair in organisms.

Question 5

Define catabolism.

Answer 5

Breaking down molecules for energy (e.g., glycolysis, cellular respiration)

Catabolism releases energy stored in complex molecules.

Question 6

What is potential energy?

Answer 6

Stored energy (e.g., chemical bonds)

Potential energy is the energy held by an object because of its position or state.

Question 7

What is kinetic energy?

Answer 7

Energy of motion (e.g., molecular movement)

Kinetic energy is the energy an object possesses due to its movement.

Question 8

What does the First Law of Thermodynamics state?

Answer 8

Energy cannot be created or destroyed but can transform or transfer.

Question 9

How do biological systems interact with their surroundings according to the First Law of Thermodynamics?

Answer 9

Biological systems are open systems, exchanging energy and matter with their surroundings.

Question 10

What is the Second Law of Thermodynamics?

Answer 10

Systems naturally move towards disorder (increased entropy).

Question 11

How do biological systems maintain order in relation to the Second Law of Thermodynamics?

Answer 11

Biological systems maintain order but increase entropy in their surroundings due to heat loss.

Question 12

Fill in the blank: The First Law of Thermodynamics states that energy cannot be created or destroyed but can _______.

Answer 12

[transform or transfer]

Question 13

True or False: Biological systems are considered closed systems according to the First Law of Thermodynamics.

Answer 13

False

Question 14

True or False: The Second Law of Thermodynamics implies that biological systems can create order without increasing entropy elsewhere.

Answer 14

False

Question 15

What does Gibbs Free Energy (AG) measure?

Answer 15

The energy available to do work.

Question 16

What characterizes exergonic processes?

Answer 16

They release energy (negative AG).

Question 17

What are two examples of exergonic processes?

Answer 17

• Diffusion
• ATP hydrolysis

Question 18

What characterizes endergonic processes?

Answer 18

They require energy input (positive AG).

Question 19

What are two examples of endergonic processes?

Answer 19

• Active transport
• Biosynthesis

Question 20

What is energy coupling?

Answer 20

Combines exergonic reactions with endergonic reactions to drive biological processes.

Question 21

What is the primary role of enzymes?

Answer 21

Lower the activation energy of a reaction to speed it up.

Question 22

What mechanism do enzymes use to stabilize substrates?

Answer 22

Stabilize substrates in the transition state.

Question 23

What is one way enzymes facilitate reactions?

Answer 23

Bring substrates together in correct orientations.

Question 24

How do enzymes induce strain to facilitate breaking bonds?

Answer 24

Induce strain in specific bonds.

Question 25

What do enzymes create in the active site to assist in reactions?

Answer 25

A distribution of electrical charges.

Question 26

Name the two models of enzyme function.

Answer 26

• Lock-and-Key
• Induced Fit

Question 27

True or False: The Lock-and-Key model is considered accurate.

Answer 27

False.

Question 28

Describe the Induced Fit model.

Answer 28

The enzyme and substrate undergo conformational changes for a better fit.

Question 29

Fill in the blank: The enzyme’s active site has a _______ shape complementary to the substrate.

Answer 29

[fixed]

Question 30

What factor increases enzyme activity up to an optimal point before denaturation occurs?

Answer 30

Temperature

Denaturation refers to the structural alteration of the enzyme, leading to loss of function.

Question 31

What is the optimal condition for enzyme function regarding pH?

Answer 31

Enzymes function best at their environmental pH optima.

Each enzyme has a specific pH range in which it is most active.

Question 32

How do higher substrate or enzyme levels affect reaction rates?

Answer 32

They increase reaction rates until saturation.

Saturation occurs when all active sites of the enzyme are occupied.

Question 33

What are competitive inhibitors?

Answer 33

They compete for the active site.

This type of inhibition can be overcome by increasing substrate concentration.

Question 34

What are non-competitive inhibitors?

Answer 34

They bind elsewhere, altering enzyme function.

Non-competitive inhibition cannot be overcome by increasing substrate concentration.

Question 35

What does ATP stand for?

Answer 35

Adenosine Triphosphate

ATP is known as the universal energy currency of the cell.

Question 36

How is ATP regenerated?

Answer 36

From ADP + Pi.

This process is vital for maintaining energy levels in cells.

Question 37

What is released during the hydrolysis of ATP?

Answer 37

Energy (-7.1 kcal/mol) used in cellular work.

Hydrolysis of ATP is a key reaction in energy metabolism.