Mastering Biology Chapter 8

Discipline: Biology (and other Life Sciences)

Type of Paper: Question-Answer

Academic Level: Undergrad. (yrs 3-4)

Paper Format: APA

Pages: 1 Words: 275

Question

Allo-  other

-ase  enzyme

trans-  across

extra-   outside of

kin- (kinet-)  moving

glyc-sweet

-trop-
change, turn, move

sub-  under, below

therm-   heat

Which of these is exhibiting kinetic energy? Why?
A) the high-energy phosphate bonds of a molecule of ATP B)a person sitting on a couch while watching TV C) a space station orbiting Earth D) a rock on a mountain ledgean archer with a flexed bow
Space station orbiting Earth -Kinetic energy is energy of motion

"Conservation of energy" refers to the fact that _____.
energy cannot be created or destroyed but can be converted from one form to another

Chemical energy is a form of _____ energy.
Potential or stored

In your body, what process converts the chemical energy found in glucose into the chemical energy found in ATP?
cellular respiration

What are the by-products of cellular respiration
heat, carbon dioxide, and water

What type of reaction breaks the bonds that join the phosphate groups in an ATP molecule?
hydrolysis

what is hydrolysis
breaking bonds with the addition of water

What is the highest energy form of adenosine?
Adenosine triphosphate (ATP) is the high-energy form of adenosine because it contains the most phosphate groups (three)
ATP molecules diffuse or are transported to the place where the energy is needed and deliver chemical energy from the breaking of their phosphate bonds.

Which part of the adenosine triphosphate molecule is released when it is hydrolyzed to provide energy for biological reactions?
γ-phosphate (the terminal phosphate)

Do the products or the reactants have less potential energy? What has happened in relation to heat?
the products have less potential energy than the reactants
Heat has been released to the environment

The following reaction
A --> B + C + heat
is a(n) _____ reaction.
exergonic

A(n) _____ reaction occurs spontaneously.
exergonic
In exergonic reactions the products have less potential energy than the reactants.

What reaction requires a net input of energy from its surroundings?
Endergonic
The products of endergonic reactions have more potential energy than the reactants.

In cells, what is usually the immediate source of energy for an endergonic reaction?
ATP The hydrolysis of ATP provides the energy needed for an endergonic reaction.

The reaction ADP + P --> ATP is a(n) _____ reaction.
Endergonic
Energy has been acquired from the surroundings

The energy for an endergonic reaction comes from a(n) _____ reaction.
exergonic
The energy released by an exergonic reaction can be used to drive an endergonic reaction.

What is the fate of the phosphate group that is removed when ATP is converted to ADP?
It is acquired by a reactant in an endergonic reaction.

This graph illustrates a(n) _____ reaction.
endergonic

What is energy coupling?
the use of energy released from an exergonic reaction to drive an endergonic reaction

In general, enzymes are what kinds of molecules?
proteins

Enzymes work by ____
reducing EA

An enzyme _____.
is an organic catalyst

What name is given to the reactants in an enzymatically catalyzed reaction?
substrate

As a result of its involvement in a reaction, an enzyme _____.
is unchanged

what is the correct label for A
A = energy of activation

An enzyme is ____ when it loses its native conformation of its biological activity
denatured

an enzyme is considered a ____ because it speeds up chemical reactions without being used up.
catalyst

an enzyme is considered _____ because of its ability to recognize the shape of a particular molecule
specific

A _____, such as a vitamin, binds to an enzyme and plays a role in catalysis
Cofactor

When properly aligned, the enzyme and substrate form an enzyme-substrate (ES) _______.
complex

A substrate binds to an enzyme at the _____, where the reaction occurs.
active site

In a catalyzed reaction a reactant is often called a ______.
substrate

Which statement is true of enzymes? (a) Enzymes can be either proteins or RNA molecules.(b) When a cell makes an enzyme, it makes many copies.(c) Their substrate specificity involves matching of shapes.Both (a) and (b).(a), (b), and (c).
Both a, b and c

What's false?
(1) Enzymes may change shape when they bind substrates;
(2) Enzymes provide no energy for the reaction, except collision energy;
(3) Enzymes may release substrates.
None

How can “induced fit” influence the specificity of an enzyme? (a) It can not influence the specificity of an enzyme.(b) It moves the reactive portion of the enzyme closer to the substrate.(c) The enzyme's active site changes shape to fit the correct substrate but not other molecules.
both b and c

Enzymes speed reactions mainly by ...
lowering EA

Which fact is most important in explaining how enzymes speed reactions?
High-energy collisions are less common than low-energy collisions.

In an experiment with an enzyme, the 58th amino acid seems to form a covalent bond with a substrate molecule as part of the catalytic process. What would you say?
At some point the bond between the amino acid and the substrate must break.

Which of the following is true of metabolism in its entirety in all organisms? A) Metabolism uses all of an organism's resources. B) Metabolism depends on a constant supply of energy from food. C) Metabolism manages the increase of entropy in an organism. D) Metabolism consists of all the energy transformation reactions in an organism.
Metabolism consists of all the energy transformation reactions in an organism.

Which of the following is an example of potential rather than kinetic energy? a molecule of glucose light flashes emitted by a firefly water rushing over Niagara Falls a crawling beetle foraging for food
A molecule of glucose

Most cells cannot harness heat to perform work because _____.
temperature is usually uniform throughout a cell

Anabolic pathways _____.
consume energy to build up polymers from monomers

The mathematical expression for the change in free energy of a system is Δ GH - TΔ S. Which of the following is (are) correct? Δ S is the change in enthalpy, a measure of randomness.Δ G is the change in free energy.Δ H is the change in entropy, the energy available to do work. T is the temperature in degrees Celsius.
ΔG is the change in free energy.

A system at chemical equilibrium _____.
can do no work is dead

Choose the pair of terms that correctly completes this sentence: Catabolism is to anabolism as _____ is to _____.
exergonic; endergonic

Enzymes increase the rate of chemical reaction by lowering activation energy barriers.
just a fact

Which of the following is true when comparing an uncatalyzed reaction to the same reaction with a catalyst? The catalyzed reaction will have the same G. The catalyzed reaction will consume all of the catalyst. The catalyzed reaction will be slower. The catalyzed reaction will have higher activation energy.
The catalyzed reaction will have the same G.