This is an example of incomplete dominance, when the inherited alleles of a trait blend. When these parents are paired, the Rr seeds make plants with pink flowers! And for reasons weвЂ™ll discuss below, the parent plant with red flowers is RR. This means that the parent plant with white flowers is rr.

Now letвЂ™s say that one parent plant has white flowers and another parent plant has red flowers. In this example, imagine that the trait for flower color comes in two alleles, R for red flowers and r for white flowers. We will focus on the trait for flower color as an example. Now we can move on to incomplete dominant traits. This is why R is usually dominant over r and why most people with Rr do not have red hair. So if you have an R and an r, you still have one copy of the gene that can get rid of red pigment. The job of R is to turn red pigment into brown. The R allele being dominant over r makes perfect sense when you look at the genes. (Click here for why I had to say probably.) Red hair is recessive to not having red hair. And it turns out, none of the kids will probably have red hair. In this case, each child will get an R from one parent and an r from the other. And to make things simpler, we will say that the parent without red hair has two RвЂ™s, and so is RR. In this case we know the parent with red hair probably has two r versions. Now imagine we have a parent with red hair and one without. In this example, we will represent the not-red hair version with an R and the red hair version with an r. We will focus on the trait for red hair as an example. LetвЂ™s start with what most of us learned about traits in school-dominant and recessive. A trait is actually the result of the mix of alleles that you have at a certain gene. Instead, a single gene comes in different alleles-one for red hair and one for not red hair. There isnвЂ™t a gene for red hair and a gene for not having red hair. LetвЂ™s take our red hair trait as an example.

It is these different alleles that give us different traits. But those genes come in different versions, which scientists call alleles. It is important to remember that we all have the same genes (the genes that make us people, and not cows!). One copy comes from mom and the other from dad. People (and many plants) have two copies of most genes. And so on for most traits for every living thing. A plant might have a gene that decides what color its flowers will be. For example, people have a gene that determines their blood type, and another gene that determines if they have red hair or not. ( Wikipedia, Pixabay ) Genes Cause TraitsДЄ gene is like a set of instructions for making a certain trait. Pink flowers are a classic example of incomplete dominance. Red hair is a classic example of a recessive trait. Here, the child has both traits from their parents at the same time. A parent with A blood type and a parent with B blood type can have a child with AB blood type. A great example of this is when a plant with red flowers is paired with a plant with white flowers and the seeds give plants with pink flowers.ДЇinally, there are examples when the child ends up with both parentsвЂ™ traits. This situation is called incomplete dominance.

When one parent has red hair and the other doesnвЂ™t, sometimes none of their kids end up with red hair! In this case, one trait is said to be dominant over the other recessive one. Sometimes when two parents with different traits have kids, all the kids end up with only one parentвЂ™s trait even though the children inherited both. And then finally, weвЂ™ll tackle the why of your question! There Are Different Kinds of Traits Then, weвЂ™ll review how genes cause traits. And how differences in genes affect those traits.Д«efore we go into the why, letвЂ™s back up and go over different kinds of traits. Great question! The answer has to do with how different genes work to give traits.

List of recessive and dominant traits