• Question: what even is life???

    Asked by to Sam, Nate on 17 Jun 2014. This question was also asked by .
    • Photo: Sam Connolly

      Sam Connolly answered on 17 Jun 2014:

      Tough question! Sometimes it’s not as clear as you might think. It’s usually described as anything made of one or more cells that eats things and can change the chemicals in the food to help it grow, can reproduce, which is having babies, or making seeds, or something similar to make more versions of itself, and being able to react to things going on around it. So people and animals eat food and can have babies, and can see, hear, smell, taste and feel what’s going on around them so that they can react. Plants get food from the soil to help them grow, make seeds to grow more plants, and can sense things like where water and light are around them, so they can grow in the best direction. With things like viruses its harder to say whether they’re alive though, because they aren’t cells, but they can reproduce, but only using other things’ cells.

    • Photo: Nate Bastian

      Nate Bastian answered on 17 Jun 2014:

      Good question. It turns out that there isn’t a fully accepted definition of life. Of course people have been trying to define life for hundreds of years, and in our normal lives it is obvious if something is, or is not, alive. However, every definition put forward so far results in a “grey area”, i.e. things that aren’t clearly alive or not. Sam makes a good point, are viruses alive? They can reproduce, passing genetic information from one individual to the next, but they need other things (i.e. the cells of animals or plants) to do it.

      Even more basic, there are basic chemicals that can replicate themselves, are they alive?

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