Do Now 1. What are mutations?

2. What happens during an insertion mutation?

3. What happens during a deletion mutation?

4. What happens during transcription?

5. What’s a protein?

Announcements Quizzes: I haven’t finished grading them. I’m

sorry, I will get them done ASAP. Gonzaga lost the West Coast Conference

Championship by 4 in OT . ESPN video

Prank calls: These NEED to stop or I’ll be going to the police

and filing harassment charges. I have three numbers of students who have been calling me.

Behavior:

Today INM Phenotype and genotype/ heterozygous

and homogenous Questions 1 – 3 on Bikini Bottom Genetics INM Punnett Squares Questions 4-8 on Bikini Bottom Genetics

What do we need to know to use a Punnett Square? 1. Genotype of parents 2. Which allele is dominant

Phenotype and genotype Phenotype: Physical appearance that

you see Genotype: what the DNA says

IE: Ms. Lusk has brown hair – Phenotype IE: Ms. Lusk’s mom has blonde hair

while her dad has dark hair. Her genotype is actually Bb

Capital letters are the dominant traits These are the ones that you see in a person

phenotype

Purebred = Homozygous Purebred:

Both alleles are for the same trait

Example: FF

Hybrid = Heterozygous Hybrid = The alleles are mixed; they are

for different traits

Example: Ff

Quick Check: Homozygous = stand up, Heterozygous = sit down

BB Homozygous

Bb Heterozygous

bb Homozygous

bB Heterozygous

Probability Have you talked about probability yet in

math? Probability is the extent to which something

could happen. IE: There is a large probability that if you all begin

talking, Ms.Lusk will get upset with you. Flipping a coin results in a 50:50 probability.

I have a 50% chance that if I flip a coin it will land heads.

There’s only two options (heads/tails).

Probability and Genetics In genetics, we use Punnett Squares to

help us understand the probability of something occurring within an offspring.

How are Punnett squares used? A Lot like a multiplication table. Female alleles (genes) are across the

top, and male alleles are down the left side.

R r

R

R

When the female and male alleles are “multiplied,” the result combo of the alleles gives the possible genotypes of the offspring.

RR Rr

RrRR

FIRST: Multiply the two top left columns.

Let’s try a Punnett Square! Hair Color in Humans

B = brown = dominantb = blonde = recessive

DRAW A PUNNETT SQUARE IN YOUR NOTES!!!

Let’s say Kevin Federline and Britney Spears are having a baby…

KFed is heterozygous for brown hair, so….

His genotype is

BbB

b

And Britney is homogenous for blonde hair, so….

Her genotype is

bb

b b

Bb Bb

bb bb

B

b

b b

Bb Bb

bb bb

Genotype Ratio Percentage Phenotype Ratio Percentage

Bb 2/4

2/4 50%50%

Brown Hair

2/450%

bb Blonde Hair

2/4

50%

The likelihood that an offspring will have Brown Hair is ______________ .

The probability that an offspring will have Blonde Hair is ____________ .

***Important*** Probability is the likelihood something will

happen, or the chance that something will happen.

If there is a 25% chance that your kids will have blue eyes, it does not mean that if you have 4 kids one of them is definitely going to have blue eyes!

Guided practice: Widow’s Peak

A recessive gene

W = Normal Hairline

w = Widow’s Peak

Let’s say you have two parents who are heterozygous for the gene

1. What are the chances that their offspring will have a widow’s peak?

2. What are the chances that their offspring will not have a widow’s peak but will carry an allele for a widow’s peak?

3. What are the chances that their offspring will not have a widow’s peak and will not carry a gene for a widow’s peak?

What are their genotypes?

Ww and Ww

Let’s see what happens if the parents have the following genotypes: Ww and ww

1. What are the chances that their offspring will have a widow’s peak?

2. What are the chances that their offspring will not have a widow’s peak but will carry an allele for a widow’s peak?

3. What are the chances that their offspring will not have a widow’s peak and will not carry a gene for a widow’s peak?