Which term most precisely describes the cellular process of breaking down large molecules into smaller ones?
Which of the following is a statement of the first law of thermodynamics?
Energy cannot be created or destroyed.
Which of the following statements is a logical consequence of the second law of thermodynamics?
Every chemical reaction must increase the total entropy of the universe.
Which of the following statements is representative of the second law of thermodynamics?
Cells require a constant input of energy to maintain their high level of organization.
Which of the following types of reactions would decrease the entropy within a cell?
Which of the following is an example of potential rather than kinetic energy?
a food molecule made up of energy-rich macromolecules
The mathematical expression for the change in free energy of a system is . Which of the following is (are) correct?
is the change in free energy.
A chemical reaction that has a positive is correctly described as
Why is ATP an important molecule in metabolism?
It provides energy coupling between exergonic and endergonic reactions.
Which of the following is most similar in structure to ATP?
an RNA nucleotide
Which of the following statements is true concerning catabolic pathways?
They are usually coupled with anabolic pathways to which they supply energy in the form of ATP.
When chemical, transport, or mechanical work is done by an organism, what happens to the heat generated?
It is lost to the environment.
Which of the following statements is (are) true about enzyme-catalyzed reactions?
The reaction is faster than the same reaction in the absence of the enzyme.
How can one increase the rate of a chemical reaction?
Add a catalyst
Sucrose is a disaccharide, composed of the monosaccharides glucose and fructose. The hydrolysis of sucrose by the enzyme sucrase results in
breaking the bond between glucose and fructose and forming new bonds from the atoms of water.
Reactants capable of interacting to form products in a chemical reaction must first overcome a thermodynamic barrier known as the reaction’s
A solution of starch at room temperature does not readily decompose to form a solution of simple sugars because
the activation energy barrier for this reaction cannot be surmounted.
Which of the following statements regarding enzymes is true?
Enzymes increase the rate of a reaction.
During a laboratory experiment, you discover that an enzyme-catalyzed reaction has a of -20 kcal/mol. If you double the amount of enzyme in the reaction, what will be the for the new reaction?
The active site of an enzyme is the region that
is involved in the catalytic reaction of the enzyme.
Zinc, an essential trace element for most organisms, is present in the active site of the enzyme carboxypeptidase. The zinc most likely functions as a(n)
cofactor necessary for enzyme activity.
Which of the following is likely to lead to an increase in the concentration of ATP in a cell?
an increase in a cell’s catabolic activity
When you have a severe fever, what may be a grave consequence if this is not controlled?
change in the folding of enzymes
The mechanism in which the end product of a metabolic pathway inhibits an earlier step in the pathway is known as