one thats baffled me...
Why does the sun lighten our hair, but darken our skin?
your skin darkens due to some pigment in your skin changing colour to make it more resistant to something to do with the sun - could be uv but im not sure - thats why people who have originated from places like africa etc have extremely dark skin, they have evolved to be born with it - i believe they are better evolved especially with all this global warming.
the hair getting lighter - well thats just cos the sun acts a bleach (i dont know the answer to this - my parents never told me
- fountains of knowledege they are)
EDIT: and your biology teacher didnt know - where have they recruited him from - nursrey? i know there are shortages and all - or is it just down to the standard of education these days - gcse's are a pile of **** anyway - no revision and you can pass em all and even manage a's