In ecosystems, primary consumers refer to organisms that eat producers, which are in the first level and include plants as they produce their own energy. Due to this, primary producers include mainly herbivore animals such as cows, goats, sheep, etc. Moreover, primary consumers are the prey of other animals, which are known as secondary consumers. In the image presented, the primary consumers include the grasshopper and the rabbit because the arrows indicate they feed exclusively on grass, which is the producer of this food web.
Chargaff's rules state that DNA from any species of any organism should have a 1:1 stoichiometric ratio of purine and pyrimidine bases, that the amount of guanine should be equal to cytosine and the amount of adenine should be equal to thymine.
