chapter 9

C6H12O6

Monosaccharides generally have molecular formulas that are some multiple of the unit CH2O. Glucose (C6H12O6) is the most common monosaccharide.

After completion of the citric acid cycle, most of the usable energy from the original glucose molecule is in the form of __________.

NADH

Why is the citric acid cycle called a "cycle"?

The four-carbon acid that accepts the acetyl CoA in the first step of the cycle is regenerated by the last step of the cycle.

Which process generates most of the NADH that delivers electrons to the electron transport chain?

citric acid cycle

In the overall process of glycolysis and cellular respiration, __________ is oxidized and __________ is reduced.

glucose, oxygen

Where do the reactions of the citric acid cycle occur in eukaryotic cells?

the matrix of the mitochondrion

ATP cycle

ATP is a renewable resource that can be regenerated by the addition of inorganic phosphate (Pi) to ADP. Energy released by catabolism in the cell is used to phosphorylate ADP, regenerating ATP. Chemical energy stored in ATP drives most cellular work.

In preparing pyruvate to enter the citric acid cycle, what steps occurs?

Pyruvate is oxidized and a molecule of carbon dioxide is removed. The electrons removed in this process are used to reduce NAD+ to NADH.

A molecule becomes more oxidized when it __________.

loses an electron

Most of the ATP produced in cellular respiration comes from which process?

oxidative phosphorylation

What events accompany the conversion of pyruvate to acetyl CoA before the citric acid cycle?

release of CO2 and synthesis of NADH

During aerobic respiration, how is molecular oxygen (O2) used?

to accept electrons and form H2O at the end of the electron transport chain