The number of endangered species of angiosperms in India is:

According to $IUCN-2004$,the total number of plant and animal species described so far is slightly more than $........$.

How many species of beetles are there on Earth?

Describe the number of species found on the earth.

Which of the following groups represents the minimum species diversity among vertebrates?

Given below are pie diagrams $A, B$ and $C$ related to the proportionate number of species of major taxa of invertebrates,vertebrates,and plants,respectively. Critically study and fill in the blanks $I, II, III$ and $IV$.