We are

Ofcourse, human beings "Homo Sapiens". A specie which evolved from the apes. Apes which evolved from some early vertebrates, which inturn evolved from sea life , which eventually boils down to some cyanobacteria, the originator of life according to the published theories.

Physically we are all a bunch of atoms and molecules, and we were created as a result of Big Bang. These atoms and molecules we are composed of, keep getting recycled everyday. Everyday our composition is different, but ultimately we are all a result of some comet that might have hit the earth or some fragmentation that formed it in the first place, billions of years back. We are just star dust from Big Bang.

Chemically, we are all (all species of plants/animals) organic carbon compounds with some amounts of other elements like zinc, calcium, phosphorous etc. We inhale oxygen and exhale carbon dioxide and there are many chemical reactions going on in our body to keep us alive.

Biologically we are a bunch of cells, the life forming building blocks. These cells carry information on chromosomes and genes, and they manufacture energy for us by burning the food we eat. The genes are probably what separates one specie from another and organisms within the same specie too.

So what is the meaning of alive or dead in terms of the biological, physical and chemical processes. These processes can be conducted in a science laboratory too? So what is it that makes us fit to be called alive? Soon will we be manufacturing life in the lab using the advancements made in genetic engineering? I think yes, considering the fact that scientists have already created genetically altered species of different plants and animals by disrupting the normal genes..
Would Darwin have imagined such a day would come?