Question

PLEASE HELP WITH BIOLOGY
Explain what it means for a section of DNA to be considered a molecular clock. Be sure to discuss the importance of neutral mutations in this measure of time.

Be sure to answer this question in paragraph form using complete sentences.

Answer 1

DNA sequences that can be used as molecular clocks need to be gene sequences highly conserved over time. When a sequence is conserved over long periods of time, it means that that sequence is important and that any changes to the sequence that result in changing the protein product can result in major negative consequences for the individual. These kinds of mutations are filtered out by natural selection.
Neutral mutations do not change the DNA sequence in the way that protein they produce is changed, therefore their effect is neutral. These kinds of mutations can stay in the gene and be inherited by the individual's offspring.
There is a precise rate of the occurrence of mutations, so if we count the number of neutral mutations in the same gene in different species we can determine how long ago did they diverge.

Answer 2

Answer:

Hi

By molecular clock, it is referred to the alterations that take place in the small sequences of DNA and which with the passage of time cause organisms to evolve from one to many.

In actual, the main cause of evolution in living organisms is the changes in DNA sequence of organisms, called mutations. Mutations serve as molecular clocks and today, scientists use these mutations to track back changes that took place in the organism over the course of time and to find the appropriate ancestor of organisms.

If we talk specifically about silent mutations, they are mutations that donot depict a great changing in the phenotype of organism or cause physiological abnormalities like diseases. They stay without causing any effect or harm to organisms.

However, these silent mutations if transferred to offspring during reproduction can have a substantial affect after many generation when this mutation will manifest itself. It is because this mutation can affect in combination over some other gene and cause significant effect on organism. This effect can be either harmful or dangerous. Here the organism who will be better able to adapt this mutation will survive as per the principle of natural selection and these selected organism with the passage of time can develop into entirely new specie.

This is how it works mutations work as molecular clocks and can be used to trace the ancestry of organisms.

Hope it helps!