Question

how does the gene flow affect genetic varitation?
a has no effect on genetic variation
b increases genetic variation between populations
c reduces genetic variation within a population
d increases genetic variation within a population

Answer 1

Gene flow, the transfer of genetic material between populations, can have significant effects on genetic variation. Here's how it impacts genetic variation based on your options:

- **a. has no effect on genetic variation**: This is incorrect because gene flow does affect genetic variation.
- **b. increases genetic variation between populations**: This option is also incorrect because gene flow tends to homogenize genetic variation between populations rather than increase it.
- **c. reduces genetic variation within a population**: This can be somewhat true, but it is not the primary effect since gene flow usually introduces new alleles into a population.
- **d. increases genetic variation within a population**: This is the correct choice. Gene flow generally introduces new alleles into a population, which can increase genetic variation within that population.

Thus, the best answer is **d. increases genetic variation within a population**.