Purines and pyrimidines are the nitrogenous bases found in the genetic material. Purines include Adenine (A) and Guanine (G) while pyrimidines include Thymine (T), Cytosine (C) and Uracil (U). Purines always pair with pyrimdine and keeps the strands of DNA at the same distance. THIS IS BECAUSE, PURINES ARE DOUBLE RINGED STRUCTURES AND PYRIMIDINES ARE SINGLE RINGED STRUCTURES. PAIRING OF PURINES WITH PYRIMIDINES MAINTAIN THE STRUCTURE OF THE DNA.
Structural adaptations<span> are physical features of an </span>organism<span> like the bill on a bird or the fur on a bear. Other </span>adaptations<span> are behavioral. Behavioral </span>adaptations<span> are the things </span>organisms do<span> to </span>survive. For example, bird calls and migration are behavioraladaptations<span>.</span>
Answer:
<em>the elements are listed in order of increasing atomic number.</em>
This is true, animals of the same species are usually the same type of animals. Like dogs with other dogs, and cats with other cats.