Bacteria have either DNA or RNA as genetic material. This genetic material must be able to replicate efficiently and accurately in order to make sure that offspring inherit the same genotype as the parent organism. This is possible because of genetic information.
The most true answer from these choices is:
Methyl groups most often added to guanine-cytosine base pairs because they are held by three hydrogen bonds, and this decreases the probability of gene expression.
The correct answer is: A. A change in a cell's genetic material.
Mutations occur in DNA as a result of mistakes during the DNA replication (when repair mechanisms don’t fix it) or as the result of environmental factors (e.g. UV light). Mutations can have positive impact, by increasing the genetic variation or can have negative effect, causing the diseases or cancer.
A. They live in the polar regions of the Northern and Southern Hemispheres.
