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Name: ted
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you said that recessive traits become dominant when they are defective and the gene product that is essential becomes damaged. is that the only way recessive traits become dominant in other words, are we talking only about diseases.

I believe this is a case of what you heard/read is not what I said. I'm not sure to which question you are referring. The reason some traits are dominant and others are recessive is because DNA contains instructions for making proteins. Since we are mostly constructed from protein based products, the DNA contains instructions for making most of our structures. Some of these proteins are hormones, which tell parts of our body what to do, some are structural-they hold our body together, some are enzymes which make our chemical reactions/metabolism go faster. If a trait is dominant it usually means that the instruction for making the product is there, or that the correct instruction is there. If a trait is recessive it usually means that the instruction for making the trait is either not there, it is defective, or it is different than the dominant. We get two sets of instructions for every trait. One comes from your mother, one comes from your father. Sometimes having only one copy of the instruction is sufficient to make enough of the protein so it works properly; for example if you have only one dominant copy and one recessive copy you make half the amount of the protein but that is enough to get by. If you have 2 copies of the recessive trait, ie. you have no copy of the dominant, you can't make the correct protein. If its an essential protein you may have some sort of disease. If it is a protein that isn't essential to life you may just look different than someone else. I don't really understand what you mean by recessive traits turning into dominant traits.

Van Hoeck

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