Bio Chapter 4

Question 1

Our bodies require energy to break down the
things we eat, as well as synthesize macromolecules of use to us. What else is energy required for?

Answer 1

Nutrient transport
* Protection (immune system)
* Energy storage
* Cell movement

Question 2

Bioenergetics

Answer 2

is used to describe the
way energy flows from one living
system to another.

Question 3

Chemical transformations will

Answer 3

Either release energy, or require
energy

Question 4

Metabolism.

Answer 4

Are all the chemical reactions that take
place inside cells of an entire
organism, including those that
consume or generate energy

Question 5

How is Glucose is formed in plants?

Answer 5

by combining carbon dioxide (CO2)
and water (H2O) to form glucose (C6H12O6) and oxygen (O2) using light energy as the fuel source.

Question 6

Glucose Formed

Answer 6

6 CO2 + 6 H2O —> C6 H12 O6 + 6 O2

Question 7

Burning Glucose

Answer 7

C6 H12 O2—> 6 CO2+6H2O

Question 8

How is glucose burned?

Answer 8

when animals metabolize
sugar, generating ATP

Question 9

Anabolic Pathways

Answer 9

Small molecules are built into large ones. (Energy required)

Question 10

Catabolic Pathways

Answer 10

Large molecules are broken down into small ones. (Energy released)

Question 11

which pathways are required to maintain the cell’s energy balance?

Answer 11

Both Anabolic and Catabolic pathways

Question 12

Enzyme

Answer 12

A molecule that catalyzes a biochemical reaction

Question 13

Energy

Answer 13

The ability to work or produce change

Question 14

Thermodynamics

Answer 14

The study of energy and energy transfer

Question 15

1st Law of Thermodynamics

Answer 15

Energy can never be created or destroyed; it just changes form
* All of the energy in the universe has been constant since the
beginning

Question 16

In living systems, most energy is converted into an easily useable form of energy called…

Answer 16

ATP (adenosine triphosphate)

Question 17

As energies transfer from one state to another, are the transformations 100% efficient?

Answer 17

No. Some energy is always lost in an unusable form (typically heat)

Question 18

Entropy

Answer 18

The measure of randomness or disorder within a system. (The more energy that is lost by a system to its surroundings, the less ordered and more random the system is.)

Question 19

Living systems are highly ordered, so in order to maintain low entropy, what is required?

Answer 19

A constant energy influx is required

Question 20

Kinetic Energy

Answer 20

the energy of a moving object. I.e. Bullets, rapidly moving air molecules, slow wrecking ball.

Question 21

Potential Energy

Answer 21

The stored energy within a substance
* Example: A wrecking ball high in the air is storing the energy that was used to put it there
* Potential energy converts into kinetic energy when it falls

Question 22

Chemical energy

Answer 22

is responsible for providing living cells with
energy from food.

Question 23

What energy is stored within the bonds of all the
food molecules we eat?

Answer 23

Potential Energy

Question 24

Free energy

Answer 24

Describes the amount of usable energy in a system
that is able to do work.

Question 25

What happens If energy is released?

Answer 25

The change in free energy (ΔG) ‘delta G’ is a negative number (<0)

Question 26

Exergonic reactions – energy is exiting the system

Answer 26

The end products of a reaction have less free energy than the starting material (reactants), because some of the free energy was released during the reaction.

Question 27

spontaneous reactions (similar to Exergonic)

Answer 27

Those that would occur on their own without any energy input

Question 28

When a chemical reaction absorbs energy

Answer 28

The ΔG is positive. (the product of the reaction now has more energy than the reactants)

Question 29

Activation Energy

Answer 29

small amount of energy needed to be provided in order for most chemical reactions to occur.

Question 30

Catalyst

Answer 30

A substance that helps a chemical reaction occur.

Question 31

The molecules that catalyze biochemical reactions

Answer 31

Are called enzymes. Enzymes are a type of proteins that help lower the activation energy so that they occur more easily

Question 32

What would happen without Enzymes?

Answer 32

All chemical reactions (even spontaneous ones) would take far too long to occur and life would not exist.

Question 33

Are Enzymes a type of protein?

Answer 33

Yes

Question 34

Substrates

Answer 34

Are the reactants that enzymes bind to.

Question 35

Active site

Answer 35

The specific location within the enzyme that performs the chemical reaction.

Question 36

Competitive Inhibitors

Answer 36

bind directly in the active site of the the enzyme, preventing its normal substrate from binding and lowering the production of the products

Question 37

oncompetitive Inhibitors

Answer 37

bind to the enzyme somewhere outside of the active site, causing the enzyme to change the shape of the active site and preventing it from carrying out its function

Question 38

Certain numbers of enzymes are needed to speed up/slow down the specific reaction

Answer 38

more enzyme = faster rate

Question 39

Allosteric inhibition

Answer 39

Works by indirectly inducing a conformational change to the active site such that the substrate no longer fits.

Question 40

Allosteric activation

Answer 40

the activator molecule modifies the shape of the active site to allow a better fit of the substrate.