BIOC 385 Exam 1 (Summer 2025)
questions and answers graded A+
In the absence of ATP for glutamine synthetase to use, what would happen to the concentration
of glutamine in the cell? - correct answer ✔✔The concentration of glutamine would decrease.
Which of the following best explains why statin therapy is effective for individuals with
hypercholesterolemia? - correct answer ✔✔Inhibits 3-hydroxy-3-methylglutaryl (HMG)-CoA
reductase, a key regulator of cholesterol synthesis.
The O2 generated from photosynthesis is derived from - correct answer ✔✔water molecules
that directly reduce PSII*.
The Biosphere 2 project, in Tucson, Arizona, was an experiment involving a large sealed
terrarium with humans and photosynthetic plants living in balance. Why did the project have to
be interrupted after only a few months? - correct answer ✔✔Levels of CO2 rose to dangerous
levels.
Amino acids are the building blocks for which biomolecule(s)? - correct answer ✔✔Proteins.
Which two functional groups are involved in producing a peptide bond? - correct answer
✔✔Amino and Carboxyl.
2-phosphoglycerate (2PG) is converted to phosphoenolpyruvate (PEP) by the enzyme enolase.
The standard free energy change (DG*') for this reaction is +1.7 kJ/mol. If the cellular
concentrations are 2PG=0.5 mM and PEP=0.1 mM, what is the free energy change at 37 degrees
celsius for the reaction 2PG <-> PEP? - correct answer ✔✔Using the DG = DG*' + RTln(Q), we
get -2.4 kJ/mol.
, R is the highly active form of an allosteric enzyme and T is the less active form. What would
happen to the ratio of [T] / [R] if substrate concentration is decreased? - correct answer
✔✔Increase.
In a hydrogen bond between a water molecule and another water molecule, [Fill in the blank]. -
correct answer ✔✔the hydrogen bond typically forms between the oxygen atom of the water
and the hydrogen on the other water.
The function of chloroplasts in plant cells is to convert, [Fill in the blank]. - correct answer
✔✔light energy to chemical energy.
The amino acid sequence of a protein determines its structure. Which of the following
statements is true? - correct answer ✔✔Two proteins with similar amino acid sequence should
have similar structures.
Which of the following best defines the first law of thermodynamics? - correct answer ✔✔Total
amount of energy in the universe is a constant.
What is the final molecule made from the oxidation of H20 by solar energy? - correct answer
✔✔Glucose.
What is the maximum number of covalent bonds a carbon atom can make? - correct answer
✔✔4 covalent bonds.
Red blood cells are placed into a solution of unknown solute concentration. After an hour they
have all burst open. The best explanation is that the solution [Fill in the blank]. - correct answer
✔✔had no solutes.
If the Gibbs free energy change value for a reaction is less than zero, this reaction is [Fill in the
blank]. - correct answer ✔✔Exergonic.
questions and answers graded A+
In the absence of ATP for glutamine synthetase to use, what would happen to the concentration
of glutamine in the cell? - correct answer ✔✔The concentration of glutamine would decrease.
Which of the following best explains why statin therapy is effective for individuals with
hypercholesterolemia? - correct answer ✔✔Inhibits 3-hydroxy-3-methylglutaryl (HMG)-CoA
reductase, a key regulator of cholesterol synthesis.
The O2 generated from photosynthesis is derived from - correct answer ✔✔water molecules
that directly reduce PSII*.
The Biosphere 2 project, in Tucson, Arizona, was an experiment involving a large sealed
terrarium with humans and photosynthetic plants living in balance. Why did the project have to
be interrupted after only a few months? - correct answer ✔✔Levels of CO2 rose to dangerous
levels.
Amino acids are the building blocks for which biomolecule(s)? - correct answer ✔✔Proteins.
Which two functional groups are involved in producing a peptide bond? - correct answer
✔✔Amino and Carboxyl.
2-phosphoglycerate (2PG) is converted to phosphoenolpyruvate (PEP) by the enzyme enolase.
The standard free energy change (DG*') for this reaction is +1.7 kJ/mol. If the cellular
concentrations are 2PG=0.5 mM and PEP=0.1 mM, what is the free energy change at 37 degrees
celsius for the reaction 2PG <-> PEP? - correct answer ✔✔Using the DG = DG*' + RTln(Q), we
get -2.4 kJ/mol.
, R is the highly active form of an allosteric enzyme and T is the less active form. What would
happen to the ratio of [T] / [R] if substrate concentration is decreased? - correct answer
✔✔Increase.
In a hydrogen bond between a water molecule and another water molecule, [Fill in the blank]. -
correct answer ✔✔the hydrogen bond typically forms between the oxygen atom of the water
and the hydrogen on the other water.
The function of chloroplasts in plant cells is to convert, [Fill in the blank]. - correct answer
✔✔light energy to chemical energy.
The amino acid sequence of a protein determines its structure. Which of the following
statements is true? - correct answer ✔✔Two proteins with similar amino acid sequence should
have similar structures.
Which of the following best defines the first law of thermodynamics? - correct answer ✔✔Total
amount of energy in the universe is a constant.
What is the final molecule made from the oxidation of H20 by solar energy? - correct answer
✔✔Glucose.
What is the maximum number of covalent bonds a carbon atom can make? - correct answer
✔✔4 covalent bonds.
Red blood cells are placed into a solution of unknown solute concentration. After an hour they
have all burst open. The best explanation is that the solution [Fill in the blank]. - correct answer
✔✔had no solutes.
If the Gibbs free energy change value for a reaction is less than zero, this reaction is [Fill in the
blank]. - correct answer ✔✔Exergonic.
