Info: The individual kernels of corn are a stage in the life cycle of a corn plant. Each kernel develops from a separate fertilization of an egg to form a zygote, a seed. The kernels in the above diagram represent individuals of an F2 generation. They have been produced from a parent cross that was pure-breeding.
S - smooth
Y - yellow
*See attachment as well*
Thank you!
Note* I would post these questions separately but they are all linked to the same information and not separated questions. It was more efficient to post them together.
Questions:
1. So far we have calculated the theoretical probability of F2 generation genotypes and phenotypes. The image in the information above represents a corn sample of F2 generation.
Identify the number of corn kernels that represent the four phenotypes.
yellow smooth ___ yellow wrinkled ___ purple smooth ___ purple wrinkled ___
2. Use the information from the previous question(s). Calculate the observed probability of the four possible phenotypes. This is calculated as the total number in a phenotype category divided by the total number of corn kernels in the sample.
yellow smooth ___ yellow wrinkled ___ purple smooth ___ purple wrinkled ___
3. Use the information from the previous question(s). Corn cobs representing an F2 generation were distributed randomly to groups in a Biology 30 class. Their group results appear in the above chart. Combine your phenotype result with that of other five groups. Calculate the totals for each phenotype and the total number of kernels (seeds) of all the corn cobs.
The pooled data provides you with a large sample of an F2 generation to help you calculate the actual (experimental) genotype and phenotype ratios that can be observed in real life.
yellow smooth ___ + yellow wrinkled ___ + purple smooth ___ + purple wrinkled ___ = total ___
4. Use the information from the previous question(s). Using the data from the combined results of the class, calculate the observed percentage for each phenotype. (Use: phenotype number divided by the total multipled by 100% = __ %.)
yellow smooth ___ yellow wrinkled ___ purple smooth ___ purple wrinkled ___
5. How does the corn cob that you analyzed (observed probability) compare with the expected results of a 9:3:3:1 ratio of dihybrid cross with both parents heterozygous in both traits?
6. Interpret your observed experimental results with the expected results of a dihybrid cross. Why were they similar / different?