7.3 Study Guide

Question 1

Compare and Contrast Cellular Respiration and Combustion

Answer 1

CELLULAR RESPIRATION: 1) stores released energy in large amounts of ATP, 2) energy is released in small amounts at a time, 3) enzymes lower the amount of initial energy needed to start the reaction, 4) happens inside of all types of cells. COMBUSTION: 1) requires a boost of energy to start, 2) large amounts of thermal energy released all at once. BOTH: 1) releases energy, 2) similar reactants (carbon based molecules + 02), 3) same final products (CO2 + H2O)

Question 2

All organisms use cellular respiration to ________?

Answer 2

Transfer the energy stored in oxygen and glucose to a usable form.

Question 3

Bond breaking _____________________________________energy

Answer 3

requires

Question 4

Bond formation ____________________________________ energy

Answer 4

releases

Question 5

Breaking a bond and forming the same bond ______________________________________

Answer 5

results in no net energy change

Question 6

An exergonic reaction is a metabolic process is accompanied by _______?

Answer 6

the release of energy

Question 7

Explain why cellular respiration is considered an exergonic reaction.

Answer 7

cellular respiration releases energy in the form of ATP throughout the process, meaning the reaction has a release of energy and is exergonic.

Question 8

What is the Equation for Cellular Respiration in the Presence of Oxygen?

Answer 8

Glucose + Oxygen ———> CO2 + H20 + Energy

Question 9

In cellular respiration, special proteins in the cells called _______ bring the oxygen and sugar together providing the boost to start the chemical reaction.

Answer 9

Enzymes

Question 10

Cellular respiration does not release the large amounts of thermal energy that are released by ___________. This is because cellular respiration breaks down sugar molecules in many small steps, each of which releases ________________________ stored in sugar and oxygen. Some of this energy is released as ____________, which helps to maintain temperature homeostasis. But the rest of the energy from cellular respiration is converted into ______________, which is energy stored in the bonds of molecules. _______ is the main molecule used for storing and carrying energy in cells.

Answer 10

Combustion; a small amount of the total energy; thermal energy; chemical energy; ATP

Question 11

Over ________molecules of ATP can be produced with the energy released per glucose molecule during cellular respiration in the presence of oxygen.

Answer 11

30

Question 12

Energy from cellular respiration is used by the human body for three main activities over the course of the day:

Answer 12

1. Resting metabolism (the chemical reactions that keep your brain and other organs, including your heart and lungs, going when you are at rest)
2. Physical activity
3. Digesting and metabolizing food

Question 13

Define Metabolism

Answer 13

All chemical reactions of life

Question 14

Define Anabolic Reactions

Answer 14

Making larger molecules out of smaller molecules (example: Dehydration Synthesis)

Question 15

Define Catabolic Reactions

Answer 15

Breaking down larger molecules into smaller molecules (example: Hydrolysis)

Question 16

Define Exergonic Reaction

Answer 16

A reaction that releases energy

Question 17

Define Endergonic Reaction

Answer 17

A reaction that requires energy

Question 18

Define Hydrolysis Reaction

Answer 18

a chemical reaction where a water molecule is used to break down a larger molecule into smaller components by splitting a chemical bond within it (requires energy)

Question 19

Define Synthesis Reaction

Answer 19

a type of reaction in which multiple reactants combine to form a single product.

Question 20

Are hydrolysis reactions exergonic or endergonic? Catabolic or Anabolic?

Answer 20

Exergonic (net release of energy) and Catabolic (break down larger molecules into smaller ones)

Question 21

Are dehydration synthesis reactions exergonic or endergonic? Catabolic or Anabolic?

Answer 21

Endergonic (net absorption of energy) and Anabolic ( make larger molecules our of smaller ones)

Question 22

What is the Structure of ATP?

Answer 22

Nitrogen base (adenine)
Sugar Ring (Ribose)
3 phosphate groups held together with high energy bonds.

Question 23

Describe the ATP cycle

Answer 23

In the ATP-ADP cycle, energy is released from ATP when a phosphate group is removed forming ADP. ADP is then changed back into ATP when a phosphate group + energy is added. ADP is recycled. What is not being recycled is energy and the phosphates.

Question 24

What does a graph of an exergonic reaction look like in terms of energy of reactants and products?

Answer 24

the energy level of the reactants will be higher than the energy level of the products (the reaction releases energy)

Question 25

What does a graph of an endergonic reaction look like in terms of energy of reactants and products?

Answer 25

the energy level of the products will be higher than the energy level of the reactants (the reaction needs to absorb energy to proceed)

Question 26

Is an anabolic reaction exergonic or endergonic?

Answer 26

endergonic because it requires energy to make larger molecules from smaller molecules (it absorbs more energy than it releases)

Question 27

Is a catabolic reaction exergonic or endergonic?

Answer 27

exergonic because it releases energy by breaking down large molecules into smaller ones (releases more energy than it absorbs)

Question 28

What part of the ATP cycle is a catabolic reaction?

Answer 28

Removal of a Phosphate from ATP forming ADP (also releases energy)

Question 29

What part of the ATP cycle is an anabolic reaction?

Answer 29

Adding a Phosphate to ADP creating ATP (requiring an addition of energy)

Question 30

Give an example of an exergonic reaction being linked (coupled) with an endergonic reaction and why they must occur in that order.

Answer 30

Glucose Breakdown (exergonic) and ATP Synthesis (endergonic) are linked (coupled) reactions with Glucose Breakdown occurring first to release and then provide the energy ATP synthesis needs in order to occur. If Glucose Breakdown didn’t happen first the energy needed for ATP Synthesis wouldn’t be available and the reaction would not take place.

Question 31

Explain the purpose of a molecule of
ATP and where most of the energy is
stored in the molecule.

Answer 31

ATP (adenosine triphospahte) serves as the primary energy carrier of a cell. Most of the energy is stored in the bonds between the phosphate groups.

Question 32

What is Activation Energy?

Answer 32

The initial energy needed to start a chemical reaction

Question 33

What reduces the Activation Energy?

Answer 33

Catalysts

Question 34

What is Gibbs Free Energy

Answer 34

The energy associated with a chemical reaction that is able to do work. Gibbs Free Energy= Energy of the Reactants - Energy of the Products