Like mites and spiders, ticks are arachnids. The brown dog tick (Rhipicephalus sanguineus) and the American dog tick (Dermacentor variabilis), examples of ticks that commonly affect dogs, require three feedings to complete their life cycles.
The citric acid cycle, also known as the Krebs cycle or tricarboxylic acid (TCA) cycle, is a series of chemical reactions in the cell that breaks down food molecules into carbon dioxide, water, and energy. In plants and animals, these reactions take place in the mitochondria of the cell as part of cellular respiration.
The citric acid cycle (see Fig. 19-1) is an ingenious series of reactions that oxidizes the acetyl group of acetyl-CoA to two molecules of CO2 in a manner than conserves free energy for ATP generation. 8 enzymes make 2 CO2 molecules and 3 NADH and one FADH2 and one GTP.