Exam 8: Energy, Enzymes, and Metabolism

Refer to the diagram below showing the activity of several enzymes at varying pH levels. Based on the diagram, achieving the maximum rate of both chymotrypsin and arginase activity in the same reaction would require a pH of about

Anabolic reactions

The energy currency of cells is

Which enzymes are most likely to not be affected by an increase in temperature?

You are given a solution in which a biochemical reaction is occurring, and you are unsure whether G is positive or negative.You suspect that the reaction might make use of the ATP to ADP + P_i energy-coupling system.To test whether it uses this system, and to determine whether the reaction is exergonic or endergonic, you would add _______.If the reaction _______, you would conclude that it is _______.

The creation of ATP from ADP requires the addition of

A reaction with a negative G

-lactamase is an enzyme that catalyzes the hydrolysis of the antibiotic penicillin.Infrared spectra taken of penicillin free in solution and penicillin bound to the active site of the enzyme have revealed that certain bonds are stretched to a greater extent when penicillin is bound to the enzyme.Explain how this observation relates to the concept of enzyme-induced strain.

Refer to the table below. Predict which reactions are most likely to be coupled to ATP hydrolysis in a cell.

An RNA molecule that has enzyme activity is called

The breaking down of molecules in a living system is known as _______.

During photosynthesis, plants use light energy to synthesize sugars, using the carbon in carbon dioxide.They do not make new energy in this process; they merely convert it from light energy to chemical energy.Photosynthesis is thus an illustration of

The formation of covalent bonds between active site side chains and the substrate is an example of _______ catalysis, whereas the transfer of protons between active site side chains and the substrate is an example of _______ catalysis.

Refer to the figures below showing changes in free energy for two reactions that are coupled together in a metabolic pathway. ATP hydrolysis is an example of reaction A that is coupled to reaction B in order to provide it with sufficient _______ to allow the reaction to occur.

Enzymes are highly sensitive to pH and temperature because

Discuss the meaning of the term "thermodynamics," and explain how biological systems and thermodynamics are related.

The conversion of glucose to glucose 6-phosphate is an enzyme-catalyzed reaction.During this reaction, the enzyme hexokinase folds around the substrates to bring reactive side chains from the active site into alignment with the substrates.This change in hexokinase is an example of

Refer to the table below. In a cell, these two reactions are coupled.Explain what that means and the benefit of having the reactions coupled.Include a diagram in your explanation.

Which statement can be used as evidence that living systems obey the first law of thermodynamics?

Which of the following affects the rate of a reaction?