Deadly diseases ;) Glad to help!!
Answer:
Because DNA molecules are extremely long.
Explanation:
DNA molecule is made up of only four types of nucleotides that are adenine, guanine, cytosine, and thymine. These four types of nucleotide encode all the information necessary for the formation and working of the entire organism because each DNA strand is as long as 2 meter which contains millions of base pairs.
The four nucleotides are arranged in the DNA strand with many different combinations which results in the formation of codons sequence that contains all the information about the cell. This long DNA is compressed several times to fit in the nucleus.
<span>The correct answer is B. Pulmonary. The answers C. Cerebral and D. Extremity, are baseless regarding this question; A. Systemic could be a good alternative, as the blood flows from the systemic to the pulmonary circulation in the right side of the heart; but the systemic circulation is in fact mostly handled in the left side of the heart, while the right side handles the pulmonary one. </span>
