Download Mendelian Genetics

Mendelian Genetics
In this activity you will be completing monohybrid
and dihybrid crosses. You will be dealing with Pea
plants and making crosses with certain plants. You
should give the genotypic and phenotypic ratios.
Show all work.
A list of traits and Dominance or Recessiveness.
Position of flowers- Axial or Terminal = Axial Dominant
Height of plant-Tall or short = Tall Dominant
Pod Appearance-Inflated or Constricted =Inflated Dominant
Pod Color-Green or Yellow =Green Dominant
Seed Texture- Smooth or Wrinkled = Smooth Dominant
Seed Coat Color- Green or White = Green Dominant
Seed Color-Green or Yellow = Yellow Dominant
Using the above information perform the crosses given and show all work. Punnett squares, Phenotypic and Genotypic ratios (on Separate Piece
of Paper)
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If a Homozygous tall plant was crossed with a homozygous short what would be the outcome?
If you crossed a heterozygous plant with a short plant, what would be the outcome?
If you crossed a heterozygous individual plant with a green seed coat with an individual with a white seed coat what would be the
outcome?
If you crossed two homozygous individuals, one having axial flowers and one having terminal flowers, what would be the outcome?
If you completed a monohybrid cross that resulted in 220 plants with green pods and 185 plants with yellow pods what would be the
parents? Show all Punnett Squares and give justification for your answer.
Use OMIM database http://www.ncbi.nlm.nih.gov/omim on NCBI and look up and example of a recessive human disease and a
dominant one. Write a short summary.
7.
If you crossed an individual plant that had yellow seeds and was tall (heterozygous for both) with an individual that was tall and had
green seeds ( heterozygous for one) what would be the outcome?
8. If you crossed a plant that was heterozygous for pod color and homozygous recessive for height with a plant that was recessive for each
trait what would be the genotypic and phenotypic ratios?
9. Dihybrid human genetic disorder problem. Achondroplasia is a dominant human genetic disorder that causes a type of dwarfism.
Cystic fibrosis is a recessive genetic disorder that causes lung damage because of defective chloride ion transport channels found in cell
membranes. Sally is heterozygous for Achondroplasia and is a carrier of cystic fibrosis. Bob is standard height and has cystic fibrosis.
They just found out they are expecting a baby. Use a dihybrid Punnett square to determine the probability that the baby will genetically
“normal” (NOT have Achondroplasia and NOT have cystic fibrosis).
10. You have a tall pea plant that has green pods. What type of pea plant would you breed it with to determine the genotype of your tall
pea plant that has green pods? Justify your answer.
Refer to Bozman biology Chi squared video if you get stuck on the next two questions.
https://www.youtube.com/watch?v=WXPBoFDqNVk
11. Do a simple Chi Squared test the null hypothesis.. Two tall plants are bred with the result of 282 Tall: 160 short. It is hypothesized that
this observed ratio is the “statistically the same” as an expected 3Tall:1Short Ratio produced by two heterozygous Tall plants breeding.
Use the 0.05 Chi Squared Critical Value with 3.841.
12. A yellow round seed producing pea plant is crossed with green wrinkled seed producing pea plant. The result was 92 yellow round: 104
yellow wrinkled: 96 green round: 108 green wrinkled. It is hypothesized that the yellow round seed producing plant was YyRr, thus
procuring an observed ratio that is “statistically the same as” expected 1 yellow round: 1 yellow wrinkled: 1 green round: 1 green
wrinkled produced when (YyRr X yyrr). Perform a Chi squared test of the null hypothesis. Use the 0.05 Chi Squared Critical Value
with 7.815.