Earth was formed some 4.6 billion years ago. It is
the life supporting planet with land forms like mountains, plateaus, glaciers,
etc., Life on earth exists within a complex structure called biosphere. There exist many mysteries
and wonders in the living world some are not visible but the activity of some
capture the attention of all. For example the response of sunflower to the
sunlight, the twinkling firefly in the dark forest, the rolling water droplets
on the surface of lotus leaf, the closure of the leaf of venus fly trap on
insect touch and a squid squeezing ink to escape from its predator. From this
it is clear that the wonder planet earth harbors both landforms and life forms.
Have you thought of DNA molecule? It is essential for the regulation of life
and is made up of carbon, hydrogen, oxygen, nitrogen and phosphorus thus
nonliving and living things exist together to make our planet unique.
According to a survey made by Mora et al., 2011 the number of estimated
species on earth is 8.7 million. The living world includes microbes, plants,
animals and human beings which possess unique and distinct characteristic