Final answer:
The product formed when carbon dioxide is removed from pyruvate is an acetyl group, which subsequently attaches to coenzyme A to form acetyl-CoA, a key molecule in cellular respiration.
Step-by-step explanation:
When a carbon dioxide is removed from pyruvate, the product is an acetyl group, which then attaches to coenzyme A during the aerobic respiration process. This occurs in a multi-step reaction involved in cellular respiration that transforms pyruvate, the end product of glycolysis, into acetyl-CoA. The enzyme complex responsible for this transformation is known as the pyruvate dehydrogenase complex. In the initial step the enzyme pyruvate dehydrogenase removes a carboxyl group from pyruvate to release carbon dioxide.
Following this decarboxylation the remaining two-carbon molecule now an acetyl group, is transferred to coenzyme A by dihydrolipoyl transacetylase forming acetyl-CoA. This molecule then enters the citric acid cycle to be further broken down for energy production.