Question: Are cells a specific colour or can they be any colour?

Rob Stanley answered on 13 Jun 2016:

Most cells are actually transparent! This means we can look inside them under a microscope.

Some do have colour however: red blood cells are red due to the iron inside them, and melanin causes our skin to be brown.

Some cells (like those in jellyfish) are fluorescent (they give out light). We’ve learnt how they do this, and often make cells fluorescent in the lab to keep track of them, and see what they are doing, under the microscope!