Answer:
DNA is the genetic material of all the living organism except some viruses. The structure and the characteristics of the DNA was well explained by Watson and Crick.
DNA is a double stranded molecule in which nitrogenous bases are linked together. Watson and crick explained that DNA strand are antiparallel. The antiparallel nature of the strand means one DNA gas a polarity of 5' to 3' direction whereas the another strand of the DNA gas polarity of 3' to 5' direction. These two strands has opposite polarity and runs in anti parallel directions. Thus, the DNA strand known as antiparallel strands.
Receptor specificity Physical energy such as light, sound,
and heat is detected by specialized receptor cells in the sense
organs—eyes, ears, skin, nose, and tongue. When the action potential that
relays information about the stimulus through the nervous system to the brain. Sensory
receptors take in information from the environment, creating local electrical
currents; These currents are graded.