Thymine and cytosine are classified as "Pyrimidines" and have one ring of carbon and nitrogen atoms for each base.
Do you have the answer choices ?
CENTRAL NERVOUS SYSTEM INCLUDES THE BRAIN AND SPINAL CORD.
<span>Classification systems are only as good as the criteria used to create them. Over time, those criteria that are considered "obsolete" will be trashed and new criteria developed. In this way, systems stay both relevant but able to reach across generations.</span>
The condition of the AIDS (Acquired Immunodeficiency
Syndrome) is caused by a virus called HIV (Human Immunodeficiency Virus). The
virus itself attacking the definite type of immune system cell inside the body.
Its cell also known as the helper cells or CD4 helper lymphocyte cells particularly
in the adaptive immune system. HIV ruining these cells, it’ll make so hard for
the body to combat off and guard off other infectious diseases. When people
gets HIV, even slight infection like fever or colds can be much critical
because the body itself has difficulty healing. Hence, immune system of one’s
person will be lowered because the helper cells are slowly being destroyed and it
makes the person unsafe.