Co dominant inheritance
Pages 322 -323 & 329-330
1. Explain co dominance.
a. How do the offspring look?
2. Give an illustration of co dominance.
3. Describe a human disorder that is inherited in this way.
A horse trainer at the rodeo had the most beautiful roan
colored colt. His coat had an even mixture of white and
chestnut colored hairs. When asked about the breeding of this
colt, the trainer stated that the color of the colt was a surprise
because the colt’s mother was chestnut and his father was
white. The trainer had expected to get either a white or
chestnut colt. How did the colt get a roan colored coat? On
the opposite page draw a Punnett Square showing this cross
and answer the questions at the bottom of the page.
What percent of my garden will be made up of pink
flowers?
What percent will remain white?
What percent will remain red?
Will the future white and red flowers be purebred?
Mendelian Inheritance
Pages 262-264
1. Explain the rule of dominance.
2. In simple dominant / simple recessive inheritance which
trait is expressed in the F1 generation?
3. If two of the F1 generation are crossed what would be
the genotypic ratio of the F2 generation?
4. What percentage of the F2 generation would express
the dominant trait? The recessive trait?
Modes Of
Inheritance
Incomplete dominance Inheritance
Pages 321-322
Key:
Chestnut Mare ______ White Stallion ______
1. Explain incomplete dominance and how it produces a
third phenotype.
2. Give an example of incomplete dominance.
I planted my garden with pure bred red snapdragon flowers
and pure bred white snapdragon flowers. After some time pink
snap dragon flowers began to grow in my garden. On the
opposite page draw a Punnett Square illustrating this. After
some time my entire garden was composed of pink snap
dragons. One day a red snapdragon reappeared and then a
white snapdragon reappeared. Eventually my garden was
composed of red, white, and pink snapdragons. On the
opposite page draw a Punnett square illustrating this and
answer the question at the bottom of the page.
Key:
Red ______ White _______ Pink ______
If the colt mates with another roan colored horse what
are the chances of getting a white offspring?
Sex linked inheritance
Pages 325 – 326 & 332-333
1. Explain sex linked inheritance
a. Give an example
Key:
Woman _______
Man _______
2. Why are more males affected with X linked
disorders?
3. Explain why a female is a carrier of an X –linked
disorder
4. How can a female be affected with a X linked
disorder
A woman who is a carrier for red/green color blindness (X
X) marries a man who’s vision is normal (X Y).
On the
opposite page create a Punnett Square. Use the Punnett
Square to answer the questions at the bottom of the page.
Explain why the man is the father of the third baby,
Multiple Alleles
Pages 323-324 & 330-331
1. Explain inheritance with multiple alleles
Polygenic Inheritance
Pages 326 -327 & 333-334
2. Give an example of multiple allele inheritance
1. Explain polygenic inheritance
3. Will the offspring always look like one or the other
parent?
A woman with type B blood marries a man with type A blood.
Their first child had type A blood, their second child had type B
blood, but their third child had type O blood. How is it possible
that the woman’s husband is the father of this baby? On the
opposite page draw a Punnett Square that supports your
answer.
2. What are some traits that are controlled thru
polygenic inheritance?
3. How would the genotype of a polygenic trait be
written?
4. Give an example of polygenic inheritance.
Explain how you know these traits are polygenic.
What is the probability of their son being color blind?
What is the probability of their daughter being color
blind?
What is the probability of their daughter being a carrier
of the red/green color blind allele?