Answer: They use carbohydrate or better known as starch, and they also use lipids to store energy
Explanation: ^^
There is variation within the population, due to a mutation. The selection pressure is the drug. The microbes that have the advantageous gene which makes them resistant to the drug are selected for, and reproduce passing on the gene, increasing its allele frequency within the population over time. However, the microbes that do not have the advantageous gene, cannot survive and their number decreases within the popullation.
Answer:
Option C. is correct.
Explanation:
According to Chargaff's rules, DNA (Deoxyribonucleic Acid) from any species of an organism should have purine and pyrimidine bases in the ratio 
This ratio is very important for solving the structure of DNA.
As per this rule, DNA is double-stranded, and covalent bonds between identical nucleotides hold the strands together.
So, Option C. is correct.
Answer:
Variations are caused by mutation. random mating between organisms.
Explanation:
<span>The lack of melanin tends to correlate with a lighter skin color. However, it also correlates with a higher susceptibility to receiving a sunburn. The more often a person burns, the more likely it is that a person will be susceptible to skin cancers later on in life.</span>
