Natural Selection?

Originally posted by whodey
It seems to me in order to test the theory you must test the theory, no?

Yes. So?

Originally posted by whodey
So what you are saying is that the scientific classifications for living and nonliving organisms are not valid? You must because I am merely going by them.

I don't think there is a clear scientific definition for what defines "life". What definition are you using?

However, generally biologists often claim life must be made of cells. By this definition, RNA is not alive. You need to be clear about what makes something a cell though or it will get confusing when looking at other structures that have some of the characteristics of cells - structures whose existence or possible existence is hypothetical at this time.

Originally posted by whodey
Come on now Scotty, you know what I mean. A cell is the smallest structual unit of an organism that is capable of independent functioning. We are not talking about the "building blocks". At first you said you needed a million dollars and a hundred years to create life and now you telling me this? I guess thats a bargin compared to Frogstomp who said a billion dollars is needed.

I thought that back in the mists of time mitochondria wee separate to 'cells'?

Originally posted by ivangrice
I thought that back in the mists of time mitochondria wee separate to 'cells'?

Indeed, this explains why they have two plasma membranes (their own and the vesicle they were encapsulated in). It also explains why they have their own genetic code too. This is a clear case of a system becoming more complex. The virus discussion I started earlier shows a simple non-living entity which could, with only a couple of changes, become a "living" system. This is probably how life evolved. If we were to try and use our current definitions of life on the very early evolution of life, they probably wouldn't work.

Originally posted by AThousandYoung
I don't think there is a clear scientific definition for what defines "life". What definition are you using?

However, generally biologists often claim life must be made of cells. By this definition, RNA is not alive. You need to be clear about what makes something a cell though or it will get confusing when looking at other structures that have som ...[text shortened]... ics of cells - structures whose existence or possible existence is hypothetical at this time.

My definition of life is a state of being alive; quality manifested by metabolism, growth, reproduction, and adaption to environment. I suppose you could say that RNA is part of a living structure, however, I would say that giving that structure life is of the supernatural realm.

Originally posted by whodey
My definition of life is a state of being alive; quality manifested by metabolism, growth, reproduction, and adaption to environment. I suppose you could say that RNA is part of a living structure, however, I would say that giving that structure life is of the supernatural realm.

Now you just have t define metabolism, as opposed any other chemical reaction, growth as opposed to accretion, reproduction (in a biological sense) as opposed replication, and "adaption to environment" as opposed to simple physical changes which can be attributed to environmental factors (such as sun bleaching)