1. Genetics

2. Questions?
If you still have questions on Punnett squares and genetics once you’ve been through the PowerPoint, watch YOUTUBE videos. Also, write down you questions for me to answer in class.
Here are a couple helpful YouTube Link:
google&feature=fvwrel&v=prkHKjfUmMs&rl=yes&nomobile=1

3. the same

4. On an even page in your notebook draw the picture to the right and fill in each line with descriptions from the list below.
Genotype
Phenotype
Trait
Purebred
Hybrid
Homozygous Dominant
Homozygous Recessive
Heterozygous
Allele
Dominant Allele
Recessive Allele
Genotype
Genotype
Genotype
Homozygous Dominant
Homozygous Recessive
Heterozygous
Purebred
Purebred
Hybrid
Trait
Phenotype
Trait
Phenotype
Genotype
Trait
Trait
Allele
Dominant Allele
Genotype
Hybrid
Heterozygous

5. Answer the following questions beside your chart.
Traits #
Detached Earlobes
Attached Earlobe
Dimples
No Dimples
Freckles
No Freckles
Cleft Chin
No cleft
Brown / Black hair
Blonde Hair
Brown Eyes
Gray / Blue Eyes
Answer the following questions beside your chart.
What is the difference between a dominant and recessive allele?
The dominant allele is always expressed when present (HH , Hh).
The recessive allele is only expressed when the dominant is absent (hh).
If you were a scientist and only had a chart of a populations traits, how could you decide what traits were dominant and what were recessive?
The traits that had the highest number in the population would be dominant. There are three different genotype combinations HH , Hh , hh. The dominant allele has a 2/3 chance of being expressed over a recessives 1/3 chance.

6. Punnett square #2 is incorrect
Punnett square #2 is incorrect. The Alleles move straight down or straight across. They can not be moved diagonal into the Punnett square.
The upper case A is incorrect. It should be two lower case a’s
a a
A a
A a aa a Aa Aa a aa A a Aa Aa aa aa Aa Aa aa Aa 1 2 3

7. How to complete a Punnett Square – Write on blank side of half sheet
Step 1 – Draw the 4 square
Step 2 – Put parent allele’s on the outside of Punnett square.
Trait – Eye Color
Alleles - Brown Eyes and Blue Eyes
E = Brown
e= blue
Male / Father alleles
E e
Female / Mom Alleles E e

8. EE Ee ee Ee E e Trait – Eye Color Alleles - Brown Eyes and Blue Eyes
Male / Father alleles
E e
Step 3- Bring dad alleles down
Bring mom alleles across
Step 4- Determine probability/percentage of each genotype
Percentage -
75% chance of brown eyes
25% chance of blue eyes
Female / Mom Alleles E e EE Ee ee Ee
Trait – Eye Color
Alleles - Brown Eyes and Blue Eyes
E = Brown
e= blue

9. G g g Gg gg
gg is homozygous recessive and 50% Gg gg
50%
T T
100% t Tt Tt Tt Tt
tt is homozygous recessive and 0 %