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Have you noticed that you are different to your relations, parents or carers, your next

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door neighbour, the kid who lives across the street, and everyone else on the planet?

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In fact, you are unique.

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But do you really know why you are different?

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Why are we all different to each other?

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Why does any organism have different characteristics to another organism?

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The answer lies in a long running debate called nature vs nurture, or genetics vs environment,

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which is a little less catchy.

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Nature refers to our genetics, the unique combination of genes that we have naturally

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inherited from our biological parents from their DNA.

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Many characteristics are controlled by our genes, including our blood group, eye colour

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natural hair color some diseases are also caused by our genes for example

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cystic fibrosis the color of a flower or a fruit is controlled by genes in plants

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nurture refers to the effect of the environment on characteristics the word

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literally means care examples of characteristics that are determined by

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the environment are weight or mass which is dependent on your diet or the presence of a scar

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some diseases may be caused by environmental influences such as type 2 diabetes or coronary

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heart disease imagine a plant has not received enough sunlight or water this may influence the

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height of the plant or the number of fruits produced we would say that the environment

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has influenced these characteristics too or that a plant has been affected by nurture

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can you decide if each of these characteristics is controlled by inherited characteristics the

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environment or both where would each go on a venn diagram pause the video while you think

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did you get them all right the effect of genetics and the environment on characteristics

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has been researched using identical twins. Can you think why this is? Identical twins

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have identical DNA, so in theory should have identical characteristics. It follows that any

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differences between a pair of identical twins could be due to the influence of the environment

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on their characteristics. In fact, twins often grow up to have very different personalities

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and preferences beyond their physical similarities these studies showed that many characteristics

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are influenced by both genetics and the environment some studies actually used twins

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identical genomes as a control to prove the effect of the environment on the body

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for example one study showed how skin aged differently by comparing smoker twins with

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non-smoker twins.

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Remember that the characteristics of a living organism are influenced by its genetics and

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its interaction with the environment, so both nature and nurture are responsible.