I think the enzyme photolyase is activated by light and can repair thymine dimers caused by UV radiation. Exposure to UV radiation is the main factor that causes skin cells to become cancer cells. These enzymes are involved in the repair of ultraviolet light-induced DNA damage when activated by light absorption.
Changes in the dna are called mutations. They can occur spontaneously. Mutations can only be passed down in gametes--sperm and egg cells. with Darwins theory at mind a mutation needs to pass the test of natural selection to remain in the gene pool. So purposly making mutation or altercations may end in diseases/illnesses or in some cases death because they body can not take it.....hope this helps if it doesnt im sorry!
Since the question is incomplete, the answer will include the generalize ways that can be used to analyze evolutionary relatedness among gibbons, monkeys, and humans.
Answer:
The evolutionary relationship is important to understand the evolution of the organisms. The common ancestors and closely related species of the organisms can be known by study the evolutionary relationship of the organism.
The DNA sequence and the amino acid sequence of gibbons, monkeys, and humans are quite similar with each other. The gibbons and humans have more then 99% DNA sequence similarity. The physical characteristics, cranial capacity and anatomical characteristics of the gibbons, monkeys, and humans are more or less similar with each other.
Answer: <u>Aphotic</u><u> </u><u>zone</u>
less than 1% of sunlight penetrates the depths of the waters in the Aphotic zone
The data suggests that there is no change in height of sheep because of
Hardy Weinberg equillibrium.
Explanation:
Data given:
heights of 200 sheeps remains the same for two years.
reason=?
There is no change in the phenotype of the sheep population during two years as there is no effect of environmental factors, no evolution or genetic drift in the population. Such population happens due to Hardy Weinberg equillibrium.
This principle says that there will be no genetic variation in a population when no evolution causing factors are there. These factors are environmental, mutation, genetic drift, natural selection or gene flow. When no new alleles are added in the population it remains same.
Thus in case of the 200 sheeps it is assumed that they were in Hardy Weinberg equillibrium.