There is no attached table, so it could not be told precisely which of the four molecules is the DNA. But, it is known that DNA consists of deoxyribose, guanine, and phosphate.
The base unit of DNA is called a nucleotide. The nucleotide consists of a nucleobase (adenine - A, thymine - T, cytosine - C, and <u>guanine -G</u>), a monosaccharide <u>deoxyribose</u>, and a <u>phosphate </u>group. <span>By knowing this, it is easy to choose which molecule of those is the DNA.</span>
Because They Are Different From The Others.
Phytoplankton serves as food for virtually all the organisms living in an aquatic environment. It is a primary food producer and serves as the foundation of aquatic food web. If there is a decline in the amount of phytoplankton, the organisms which feed directly on the plant may reduce significantly as a result of dire competition for food, this in turn will affect the organisms which feed on the dying out organisms and the trend will move in a similar way until it affect all the organisms living in that particular aquatic habitat.