[Cameron Lapworth (OP)]

Cameron Lapworth  asked the Naked Scientists:
   
Hi Chris,

Firstly newbielink:http://www.thenakedscientists.com/HTML/podcasts/ [nonactive].  

I was wondering what mechanism causes children born to the same parents all have different characteristics from each other?

I understand that half the Chromosomes come from the father and half the Mother so you'll always get a mixture of both parents characteristics. However, this simple understanding doesn't explain why they aren't all identical twins (albeit born at different times). So are the Chromosomes somehow jumbled further say chromosomes no. 2 from Mum and no. 4 from Dad? What mechanism controls individuality?

Ta, Cameron Lapworth

What do you think?

[Bored chemist]

There's more to human development than genetics but even if you just look at the genes there's a whole lot of possibilities.
For example, My dad's tall and fair haired and my mother's short with dark hair.
In very simplistic terms I could therfore be: short and dark; short and fair; tall and dark or tall and fair.
With millions of possible traits the number of possible combinations is huge

[Make it Lady]

Genes can also lay dormant and that is why a white couple can unexpectidle have a black child. Both parent would have had a black person in there genetic make up from past generations. I think they have made a film about it recently called SKIN.

[Chemistry4me]

The chromosomes of a cell undergoing meiosis separate in different ways. If crossing over is ignored, a cell with two chromosomes can produce four different kinds of gametes; and with each additional pair of chromosomes, the number of possibilities double.

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