Question: If there is life on Mars, would its respiratory system be different to ours?

Richard Friend answered on 15 Mar 2016:

This is a really topical question – we’ve just sent a probe to Mars to find out if there’s life there today! Apparently there’s more methane there than they’d expect from normal processes, so they think there’s living things making the methane. As there’s a really thin atmosphere there any living things would have to have a completely different respiratory system to be able to survive. I’d expect that if they found life it would probably look like bacteria though, which doesn’t have a respiratory system at all.