Heredity slides and Questions

Heredity

Explained

By the most professional, but fun, teachers, Anabelle the Awesome and Emersyn the Great.

What is the difference between a Punnet square and a pedigree?

So we know that they don't sound the same, but why? Because punnet squares give us information about the offspring, while pedigrees are diagrams that allow us to visualize patterns of inheritance throughout a family's history.

Is it a girl or a boy in your pedigree?

You already know the definition of a pedigree, which is that it tracks a specific trait throughout many generations of a family. But did you also know that they can track genders too? A square resembles a male and a circle represents a female. Have you watched Spongebob? Then you will get this trick. Spongebob is square, and Mrs. Puff is a circle. Remember that to help you remember how to do a pedigree!

​Shading in a pedigree

So you can track traits in a pedigree. But how? Well, with shading of course! If the person is not shaded, then they do not carry or show that trait. If it is half-shaded, then they carry the trait. And if it is fully shaded, then they show the trait.

Open Ended

Carl is making a pedigree. He knows that in his dad's family, none of them carry or have diabetes. On the other hand, he has diabetes, but his mom does not. How should he shade his mom?

Multiple Choice

True or False: Punnet squares are similar in that they give us information about genetics, but not the same as pedigrees.

• True

• False

Alleles

A dominant allele means that it starts with an uppercase letter. Ex: the T in Tt. A recessive allele means it starts with a lowercase letter. Ex: the first t in tt. These are what you use to make a punnet square. Homozygous is when the alleles are identical. Heterozygous is when they are different. Both TT and tt are homozygous. Tt is heterozygous. Remember "homo" means one. One kind of allele.

Multiple Choice

What is Tt?

• Homozygous

• Heterozygous

Multiple Choice

What are T, and t?

• Homozygous

• Heterozygous

• Alleles

Multiple Choice

What is Tt?

• Dominant

• Recessive

Multiple Choice

Catherine is tracking freckles in her family. She found that she half-shaded both her mom and dad. Make a punnet square in classkick to find out if Catherine has freckles or not. The class code is NEY ZMI

• If you did it wrong, you got that Catherine's alleles could be FF, Ff, Ff, or ff.

• If you did it wright, you got that Catherine's alleles could be FF, Ff, Ff, or ff.

• If you did it wright, you got that Catherine's alleles could be FF, Ff, fF, or ff.

• If you did it wrong, you got that Catherine's alleles could be FF, Ff, fF, or ff

​Phenotypes

What are phenotypes you ask? Well, they are how you look. Think phenotypes start with P, and so does physical, or physical appearance. Emersyn's hair phenotype is brown, and Anabelle's eye phenotype is hazel. As long as you remember that phenotype is physical, you'll do good!

Multiple Choice

What is skin color?

• Genetics

• A kind of Phenotype

• The color of your skin

• Genotype

Genotypes

Now what is different about genotypes than phenotypes? Genotypes are extremely similar to an allele. But this time, they are in pairs. Tt is a genotype. It is a heterozygous genotype, which you learned a couple of minutes ago. It will never be written tT.

Multiple Choice

What is the T in Tt?

• A genotype

• An allele

​How to make a punnett square

Is there a proper way to write the punnett square? Yes, there is! The mom's genotype goes on the side. The father's genotype goes on the top of the punnett square. Each of the small squares in the punnett square is 25%.

Open Ended

Yay! You have finished the lesson portion of today. We are going to explain you homework. You are going to find any trait you want. This could be freckles, hair color, hair texture, a hereditary i, etc. We are using brown hair as an example. So you are going to look at your grandparents, aunts, uncles, parents, and siblings for their hair color. Then you are going to draw a simple pedigree. Make sure to include small pictures so that we can double check it if it is a visual trait. You will turn it in tomorrow, so don't forget! Now, do you think tomorrow is enough time, or do you want until the day after? Why?