Bio Review

Which part of the following intermediary metabolites enters the citric acid cycle and is formed, in part, by the removal of a carbon from one molecule of pyruvate?

Acetyl CoA.

Which kind of metabolic poison would most directly interfere with glycolysis?

An agent that closely mimics the structure of glucose but is not metabolized.

In which step in figure 9.1 is an organic phosphate added to the reactant?

C

Which of the following statements describes the results of this reaction?

C6H12O6 is oxidized and O2 is reduced.

What is the term for metabolic pathways that release stored energy by breaking down complex molecules?

Catabolic pathways

Where does Glycolysis take place in eukaryotic cells?

Cytosol.

During aerobic respiration, electrons travel downhill in which sequence?

Food --> NADH --> Electron Transport Chain --> Oxegyn

Which process in eukaryotic cells will proceed normally whether oxygen (O2) is present or absent?

Glycolysis

A molecule that is phosphorylated

Has an increased chemical potential energy; it is primes to do cellular work.

Why is glycolysis described as having an investment phase and a payoff phase?

It uses stored ATP then forms a net increase in ATP.

Where are the proteins of the electron transport chain located?

Mitochondrial inner membrane.

The free energy for the oxidation of glucose to CO2 and water is -686kcal/mol and the free energy for the reduction of NAD+ to NADH is +53 kcal/mol. Why are only two molecules of NADH formed during glycolysis when it appears that as many as a dozen could be formed?

Most of the free energy available from the oxidation of glucose remains in pyruvate, one of the products of glycolysis.

Which of the following statements describes NAD+?

NAD+ is reduced to NADH during glycolysis, pyruvate oxidation, and the citric acid cycle.

If pyruvate oxidation is blocked, what will happen to the levels of oxaloacetate and citric acid in the the citric acid cycle shown in figure 9.2?

Oxaloacetate will accumulate and citric acid will decrease.

Carbon Dioxide (CO2) is release during which of the following stages of cellular respiration?

Oxidation of pyruvate to acetyl CoA an the citric acid cycle

Why are carbohydrates and fats considered high energy foods?

They have a lot of electrons associated with hydrogen.

How many carbon atoms are fed into the citric acid cycle as a result of the oxidation of one molecule of pyruvate?

Two

Substrate level phosphorylation accounts for approximately what percentage of the ATP formed y the reactions of glycolysis?

100%

For each molecule of glucose that is metabolized by glycolysis and the citric acid cycle, what is the total number of NADH + FADH2 molecules produced?

12