The parasympathetic nervous system activates the relaxation, or rest-and-digest, response. Roughly the opposite of the fight-or-flight response of the sympathetic nervous system, the relaxation response involves restoration of energy reserves and other peace time functions, such as repair and reproduction.
On this day in 1953, Cambridge University scientists James D. Watson and Frances H.C. Crick announce that they have determined the double-helix structure of DNA, the molecule containing human genes.hough DNAâshort for deoxyribonucleic acidâwas discovered in 1869, its crucial role in determining genetic inheritance wasnât demonstrated until 1943. In the early 1950s, Watson and Crick were only two of many scientists working on figuring out the structure of DNA.
Report Abuse. DNA structure DNA structure was first described by James Watson and Francis Crick in 1953. Deoxyribonucleic acid (DNA) is a nucleic acid that contains the genetic instructions for the development and function of living organisms.All living things contain DNA, with the exception of some viruses with RNA genomes.he nucleotides are joined in such a way that they form a double helix that is like a twisted rope ladder. The steps of the ladder are made by the paired nitrogen bases of opposing nucleotides. A-T and C-G The sides of the ladder are alternating sugars and phosphates.