In terms of cell division, normal cells differ from cancer cells in at least four ways. Normal cells require external growth factors to divide. When synthesis of these growth factors is inhibited by normal cell regulation, the cells stop dividing.
According to Darwin's Theory of Natural Selection, each generation produces more individuals than the ecosystem can sustain. However, not all individuals are identical and phenotypical variation exists.
Due to this variation, some antelopes are better at escaping lions, perhaps due to speed and/or stamina. Thus, the individuals that are slower and thus less fit will be killed and eliminated from the herd. The antelopes with heritable traits that makes them better suited to the environment, will escape and thus, survive and reproduce.
In Darwin's Theory predation is an evolutionary force.
E is the answer to your question
A the production of antibodies
