Although not present in animals, many plants and animals can use a modified form of the citric acid cycle known as the glyoxylate cycle. this is beneficial in that

The benefit is that it makes the organism that has it to be able to convert Acetyl CoA into glucose precursors.

Explanation:

Note that, glyoxylate cycle overlaps the non- decarboxylation reactions of the Citric acid cycle. This can't occur in animals due to the absence of two important enzymes, isocitrate lyase and malate synthase, which are necessary for this pathway.

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