Final answer:
Genic mutations are indeed random, and they contribute to genetic variability in a population. While specific point mutations are rare, the likelihood that an organism's genome will contain at least one mutation is quite high.
Step-by-step explanation:
Are Genic Mutations Random?
The process of mutation, which generates genetic variation, is indeed random. Mutations occur spontaneously due to internal conditions in the body or external environmental factors. The exact cause of a mutation is often unknown, and the statistical distribution of mutational changes is difficult to ascertain because many mutations that are neutral or do not lead to apparent phenotypic changes go undetected.
The likelihood of a mutation in any specific gene ranges from 1 in 10,000 to 1 in 100,000 for any given gene, making specific point mutations unlikely. However, considering the entirety of an individual's genetic material, the probability that at least one mutation exists is substantially higher. Hence, while mutations are rare events, they are common enough to contribute to genetic variability across populations.
It is important to understand that mutations do not arise because of a need for them; the emergence of a beneficial mutation, such as the one that confers resistance to insecticides in mosquitoes, is not influenced by the pressures of the environment.