The fundamental property of nervous tissues which related to its function of coordinating the body's activities is that it's widely connected to all areas of the body through the spine and neuronal axons in general. Nervous tissue which is found in our brain can exert its "will" and affect all parts of our body.
A clade is a group of organisms that includes an ancestor and all of its descendants. Clades are based on cladistics. This is a method of comparing traits in related species to determine ancestor-descendant relationships. Clades are represented by cladograms, like the one in Figure below.
the youngest layer is 7(middle point) because decomposition must occur in the middle of decomposed materials.the oldest is 12(upper one) because decomposed material are found at the top most of organisms.
