Find the Punnet square page

•We filled in the first square last class period.

•Let’s practice it one more time as a class

•When we are done – glue in this page and use it as a reference tool!

On the second square…

What will the offspring be like from the cross of a white hamster and a brown hamster if the brown hamster’s mother was white?

Hint: White is recessive and brown is the dominant trait.

How do we start?

On the second square…

Brown is the dominant trait = BB

White is recessive = bb

So, white hamster can only have bb, but a brown hamster can have BB or Bb, right?

If a brown hamster is Bb, it has one brown allele and one white allele.

How do we fill in the square?

Second Square

What will the offspring be like from the cross of a white hamster and a brown hamster if the brown hamster’s mother was white?

What are the genotypes?

1. White hamster is bb, brown is Bb – so put that on the “outside” labels now.

2. Now, fill in the punnet square.

Glue in page

•Make sure to glue in the completed Punnet square example page NOW

Key Terms!

Key terms are genotype and phenotype.

•Genotype – the genetic make up of an organism•Represented in a punnet square with capital and lower case letters

•Phenotype – the physical manifestation of those genes!•Represented by color in this activity

Plastic Egg Genetics!

Procedure:

1. Each group will get a “basket” of the eggs.

2. From the basket, each student will select 5 eggs, one at a time

3. Work with your partners to follow the directions and work through the punnet squares.

Representing Genetic Traits

How does this work?

•For example, a (phenotypically) half pink and half purple egg would represent the genotype PP x pp, each half of the egg representing the genetic input of one parent.

•Then, you would do a Punnett Square to determine what offspring would be possible from such a cross.

•The Punnett Square calculation reveals that all of the offspring would be genotypically Pp, or phenotypically orange.

In pictures:

PP - purple pp - pink PP x pp

PP x pp = what would their offspring look like?

Your packet:

Work through the packet, following directions and then filling in the punnet squares.

When done, put the eggs in the basket and the basket back on the back counter.

Finally, work on the reflection question on the last page

Packet is due COMPLETED next class!

•Make sure all punnet squares are filled in

•Answer all follow up questions