Why are humans carbon based life forms?

Answer 1

Carbon makes the kind of bonds useful for the chemistry of life, and makes four of them. So does silicon, but temperatures have to be extremely high by our standards for silicon to act like carbon.

Of course, somewhere out there could be a silicon fellow explaining that carbon works like silicon, but only works at a range of extremely low temperatures!

Answer 2

It would be more correct to say that all life on Earth (at least, "life as we know it") is CHON-based, because every living molecule includes all four of the elements Carbon, Hydrogen, Oxygen and Nitrogen.

Answer 3

All life on earth contains carbon, hydrogen, oxygen, nitrogen, and sulfur. Aside from atoms of water (H2O), carbon is the primary element, and exists in all the organic molecules. They are called organic molecules chiefly because they contain carbon.

Answer 4

"Life as we know it" requires carbon; we know of no other kind.

However, at least in theory, some form of life could develop around other chemistries. Carbon has an advantage in chemical relationships because a carbon atom can form bonds with up to four other atoms, and no element can have more. Silicon, however, also can have up to four bonds at a time, so perhaps in some environments life might develop based on silicon.

Sometimes we humans can be exceptionally good at rationalizing that the way things ARE is the way things MUST BE - and since terrestrial life is based on carbon, this must be the only way. But perhaps not!

Answer 5

Life is carbon based, on Earth, because Earth is a carbon based planet.
Good question. We know that it is - but we cannot be certain WHY.

A logical explanation is possible. Carbon atoms form more molecular bonds than any other light element; four. ( Silicon also forms four bonds, but the binding strength is lower and the bonds are more likely to be broken. )

Answer 6

Good question, but the ultimate answer may be "Because it is." Many of the great "Why" questions in the sciences have no certain answers.

One possibility is that carbon, with four valence electrons, can form more complex bonds that other elements with fewer. (No element has more valence electrons.) The only competitor is silicon, also with four - but the strength of the electron bond is stronger in carbon than in silicon, so carbon-based life MAY - repeat MAY - be more sturdy than other types.

But the fact is that we have closely examined only one planet - Earth - and have only the faintest beginnings of exploration on Mars. The Moon is probably as dead as, well, the Moon. Landers on Venus and on Titan each survived for about an hour, and carried no biological analysis equipment at all. That's it; we haven't touched ANY other astronomical body.

Ask that question again in about 50 years; maybe we'll have the beginnings of an answer by then.

Answer 7

Because the element has four valency thus it cant give or loose its four electron so it doesn't gives its atoms simply it just shares it and makes life generally based around the element carbon.

Answer 8

If life did exist without carbon, it would be a very different kind of life than we are familiar with, one not based on chemistry at all.

Science Fiction is full of "silicon-based lifeforms", but the sad truth is that that's probably not thermodynamically possible. Oxygen is the third most abundant element in the universe, and in the presence of oxygen silicon is MUCH more likely to form bonds with an oxygen atom than with another silicon atom. This means that complex molecules, like those we believe necessary for life, are extremely unlikely to form (or to be stable, if formed).

Answer 9

All life as we know it at this time is indeed carbon based.

Answer 10

It is probably because of the unique chemical properties of carbon. Specifically the amazing lengths the carbon chains can form.