Q.
What is the annual net primary productivity of the whole biosphere
1. 160 billion tons
2. 170 billion tons
3. 177 billion tons
4. 190 billion tons
Ans:2. 170 billion tons
👉The annual net primary
productivity of the whole biosphere is approximately 170 billion tons
(dry weight) of organic matter
👉Of this, despite occupying about 70 per
cent of the surface, the productivity of the oceans are only 55 billion tons.
👉The world population which was around
2 billion (2000 million) in 1900 rocketed to about 6 billion by 2000 and
7.2 billion in 2011.
👉A similar trend was observed in India too. Our
population which was approximately 350 million at the time of our
independence reached close to the billion mark by 2000 and crossed
1.2 billion in May 2011.
👉DNA:The two chains are coiled in a right-handed fashion. The pitch
of the helix is 3.4 nm (a nanometre is one billionth of a
metre, that is 10^-9 m) and there are roughly 10 bp in each
👉3 billion chemical base pairs that
make up human DNA
👉approximately 20,000-25,000 genes in human DNA
👉Human genome is said to have approximately 3 x 10^9 bp, and if the
cost of sequencing required is US $ 3 per bp (the estimated cost in the
beginning), the total estimated cost of the project would be approximately
9 billion US dollars
👉The universe is very
old – almost 20 billion years old.
👉In the solar system of the milky way galaxy, earth
was supposed to have been formed about 4.5 billion years back.
👉Life appeared 500
million years after the formation of earth, i.e., almost four billion years back.
👉The first non-cellular forms of life could have originated
3 billion years back
👉The first cellular form of life did not possibly originate till about 2000
million years ago.
👉More than 840 million people in the world do not have adequate food to
meet their daily food and nutritional requirements.
A far greater number–
three billion people – suffer from micronutrient, protein and vitamin
deficiencies or ‘hidden hunger’ because they cannot afford to buy enough
fruits, vegetables, legumes, fish and meat.
