Question

1. In some detail, explain why we (as humans) should not rely on the natural selection for the ∆32 allele to produce universal or near-universal resistance to the HIV virus

2. From an evolutionary perspective, what is meant by “fitness”?

3. List three different types or categories of mutations, describe briefly how each occurs, and the consequences of each regarding genetic variations

4. Although non-random mating does not itself change allele frequencies so technically is not a mechanism of evolution, it violates one of the assumptions of H-W equilibrium. In the context of H-W, why is non-random mating so profound in terms of evolutionary biology?

Answer 1

question 2

To an evolutionary biologist, fitness simply means reproductive success and reflects how well an organism is adapted to its environment. The central concept of natural selection is the evolutionary fitness of an organism. Fitness is measured by an organism's ability to survive and reproduce, which determines the size of its genetic contribution to the next generation.

question 3

• Small-scale mutations-
• Point mutation– a change in one base in the DNA sequence.
• Substitution – when one or more bases in the sequence is replaced by the same number of bases (for example, a cytosine substituted for an adenine).
• Inversion – when a segment of a chromosome is reversed end to end.
• .Large-scale mutations- Copy number variation (CNV) is a type of mutation where large chunks of DNA are inserted, repeated or lost. These regions of DNA can be between 10,000 and 5,000,000 bases long.
• Addition of an extra copy of a chromosome. For example, an extra copy/partial copy of chromosome 21 results in Down’s syndrome.