For human species to obviate extinction, reproductive mature adults should be producing viable offspring in order to con..
DNA is a double helix structure comprised of nucleotides. A nucleotide, in turn, is made up of phosphate molecule, deoxy..
In plants, growth occurs in meristems, which are the site of repeated cell division of unspecialized cells. These cells ..
A running water environment offers numerous microhabitats for many types of animals. Similar to plants, animals in lotic..
Multicellular organisms evolved. The first ones were likely in the form of sponges. Multicellularity led to the evolutio..
Earth was created around 4.5 billion years ago and life began not long after. Primitive life likely possessed the elemen..