Which process does not occur in the krebs cycle?
a. a 4-carbon molecule is recycled.
b. glucose is broken down into two pyruvate molecules.
c. pyruvate is broken down into a 2-carbon molecule and carbon dioxide.
d. citric acid is broken down, creating carbon dioxide as a waste product.

The correct answer is b glucose is broken down into two pyruvate molecules.

Explanation:

Krebs cycle is one of the most important step of aerobic respiraion.Krebs cycle occur within mitochondrial matrix.During krebs cycle the acetyl CoA generated from pyruvate reacts with oxalo acetate in a cyclic manner to regenerate 4 carbon compound oxaloacetate.

 During krebs cycle pyruvate is broken down or oxidized to form 2 carbon compound known as acetyl CoA and carbon dioxide as byproduct.

  But the breakdown of glucose into two pyruvate molecules occur during glycolysis.

4

his research revealed two genetically different groups of prokaryotes, which justified splitting kingdom monera into two kingdoms. the genetic and cellular differences were so great, that these two kingdoms were eventually placed into different domains in the current three-domain system.