Overaeration lungs: Hyperaeration means lungs contain larger amount of air than normally expected. Has many causes. In children can be seen with diseases causing air trapping such as bronchiolitis, asthma, cystic fibrosis, congenital heart disease, early aspiration, and metabolic acidosis.
Barbara McClintock's World Discovering Jumping Genes For the first half of the 20th century, genes were seen as objects with fixed positions on the chromosomes. However, in the 1950s, Barbara McClintock showed that certain DNA fragments, termed transposons, can be activated to jump from one position on a chromosome to another.
Genetic Timeline. 1859. Discovery: Natural Selection. Charles Darwin wrote âOn the Origin of Species by Means of. Natural Selection, or the Preservation of Favored Races in the. Struggle for Life.â. 1865. Discovery: Heredity Transmitted in Units. Gregor Mendelâs experiments on peas demonstrate that. heredity is transmitted in discrete units. The understanding. that genes remain distinct entities even if the characteristics. of parents appear to blend in their children explains how. natural selection could work and provides support for.