BRAIN DUMP
Why is all life on Earth carbon-based, and would it be possible to have life that’s not carbon-based?
James Dark
■ Life needs to be able to store information, and to do this it has to construct large, complicated molecules that stand the test of time. One of the only elements that can do this is carbon. Carbon can make four bonds to other elements. This allows it to form the long, branching chains that make up our most useful molecules, from the DNA that carries our genetic code to the fats that surround our cells. The most viable alternative is silicon; it sits directly under carbon in the periodic table and can also make four bonds. However, because it’s bigger than carbon, its unpaired electrons are further away from its nucleus. This means the bonds it makes are weaker, so biological molecules based on silicon would likely be less stable. LM
Has Britain always been a monarchy?
Sebastian Rusescu
■ Britain hasn’t always been a
