Everyone in the world looks a little bit different. Why do you think that is? Now
think about your family. Do you look like your brothers and sisters or your
parents? Most likely you don't look like anyone else in your family. The question
we're trying to answer today is "Why do you look like your family or your
parents in some ways but not others?"
Well, it's because of your heredity. Heredity is the passing
of traits from parents to their children.
So, your physical features are passed down from your parents, sort of like a
favorite family recipe. Some of these traits are passed down from your mom and
some are passed down from your dad,
but you do not have exactly half from each
parent like some people think. That's why you're not an exact copy of your parents.
You may have the same color eyes as your mom but have your dad's hair
color, for example. And your siblings may not have gotten the same traits that you did.
That's why you may or may not look like your brothers and sisters. Here's a
picture of my family to illustrate.
Most siblings only have about half of the same traits. Even fraternal twins, or
the ones that don't look alike, are only as similar as any other siblings. Other
than identical twins, no two people look exactly alike. So, what kinds of traits
come from our parents?
Eye color, hair color and texture, and some health conditions come from your parents.
These are called inherited traits.
Then, traits like height, weight, the shape of your body, and your skin color are
inherited, but can also be affected by the environment. These are called
environmental traits.
For instance, your skin may get darker when you spend time in the sun.
Environmental traits don't include the changes that we made to ourselves such
as dyeing our hair though. Look at this picture of my mom and I.
As you can see, my mom's hair is curly but mine is straight. That's because she
curls it. Naturally, her hair is just like mine. Finally, just because you have it in
common with your parents doesn't mean that you inherited that trait. Your
favorite food or sport, for example, is not inherited. To illustrate, my brother
and my dad both played the same position on their baseball team but that isn't
part of your heredity.
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