Galen considered anatomy as the foundation of medical knowledge, and he recurrently dichotomized and tested on the lower animals like pigs, sheep, and goats. Galen's supported dissection as the method to better the skills of surgery and research works.
In his work, he illustrated seven pairs of cranial nerves, observed the structural distinctions between the veins and arteries, and illustrated the valves of the heart.
Nucleic acids are the biopolymers, or small biomolecules, essential to all known forms of life. The term nucleic acid is the overall name for DNA and RNA.
