And reproductive isolation
The correct answer is option glucose.
The glucose can be used as the immediate source of the energy. The cells can utilize the glucose to form the ATP molecules, which can be used as a source of energy by the body of the organism. The cellulose, chitin, and the glycogen are the polymers, they can only be utilized, once they are broken down into simpler forms.
The correct option is D.
Parietal cells are the epithelial cells which secrete hydrochloric acid and intrinsic factors. The cells are located in the gastric glands which are found in the linings of the walls of the stomach. The hydrochloric acid produced by the parietal cells helps in the conversion of the enzyme pepsinogen to pepsin during the digestion process.
