Question

1. what are the differences between DNA replication vs. PCR?

2. From gel electrolysis, what does the DNA strand look like?

3. Why is cancer a genetic disease but are not inherited?

Answer 1

1.

a. DNA replication takes place in presence of DNA polymerase where as PCR is in presence of Taq DNA polymerase.

b. DNA replication in living cell usually doubles the DNA content as one cycle occurs. IN PCR multiple cycles occur that amplify DNA billion times.

c. DNA replication replicates whole genome in one cycle. IN PCR smaller fragments of DNA are multiplied.

2.In Gel electrolysis, the DNA strand is not visible. To make it visible it has to be treated with ethidium bromide and exposed to UV radiations.

3.Cancer is a disease but not inherited as each individual has protooncogenes , Tumor supressing genes to resist occurence of cancer. When exposed to carcinogens these genes get activated to oncogenes and cause cancer. Role of environment is very important in regulating cancer/tumor formation in the body.