This is because the melanocytes are located in the stratum basale. Lighter-skinned people usually have low basal levels, and exposure to UV radiation causes an increase which makes skin darker.
Answer:
Biodervasity.
Explanation:
The term refers to the variety of life on earth.It demonstrates the extent of variation at different levels of species,genetic and ecosystem in a community of organisms.
It not equal in its distribution on earth;but rather varies with the type of ecosystem available and the distribution of biotic and abiotic factors in the ecosystem. For example;
It is highest in the Tropics,due to the species richness and diversity of the region. However, it varies in other ecosystem based on species diversity peculiar to parts of the region .e.g it is highest in the marine ecosystem along the coast of abundant temperature for primary producers.
Answer:
A malaria outbreak causing allele frequencies to change is an example of <u><em>natural selection.</em></u>
Explanation:
Natural selection is a type of selection in which those organisms are favoured to live and reproduce which are better adapted to live in an environment. Due to natural selection, the allele frequencies of a population will tend to change with the passage of time.
When the outbreak of malaria occurs, those organisms which do not catch malaria are able to survive and pass on their characteristics to their offsprings. the other organisms die and do not reproduce. This will cause changes in the allele frequencies.
