Reaction 1: Citrate Synthase. The first reaction of the citric acid cycle is catalyzed by the enzyme citrate synthase. In this step, oxaloacetate is joined with acetyl-CoA to form citric acid. Once the two molecules are joined, a water molecule attacks the acetyl leading to the release of coenzyme A from the complex. Figure %: Reaction 1.
There are three types of carbohydrates: starch, sugar and fiber. Starches and sugars provide your body with its main source of energy. They're all comprised of carbon, oxygen and hydrogen, which are organized into single units.
Carbs 101: Simple vs. Complex. Carbohydrates are made up of sugar molecules, which your body breaks down into fuel, especially when youâre working hard. Sugars, starches, and fiber are all basic forms of the carbohydrate. There are two main types of carbohydrates: simple and complex.