# What is the expected phenotypic ratio for this cross

• Test Prep
• 19
• 86% (80) 69 out of 80 people found this document helpful

This preview shows page 10 - 12 out of 19 pages.

##### We have textbook solutions for you!
The document you are viewing contains questions related to this textbook.
The document you are viewing contains questions related to this textbook.
Chapter 2 / Exercise 19
Human Heredity: Principles and Issues
Cummings
Expert Verified
What is the expected phenotypic ratio for this cross?
Table 10.4 Wing Length and Body Color in DrosophilaPhenotypesLongLongShortShort Phenotypic GrayEbony GrayBlack RatioNumber of Offspring283225301:1:1:1Class data1281201201201:1:1:1Conclusions: Wing Length and Body Color in Drosophila(LM page 112)Calculate the actual phenotypic ratio based on the data and record in Table 10.4.Doyour results differ from the expected ratio per individual data? Yes, probably Per class data? Not as much. Explain.
Give reasons for any difference in chi-square values per your data and per class data.
Two-Trait Genetics Problems (LM pages 112-113)
##### We have textbook solutions for you!
The document you are viewing contains questions related to this textbook.
The document you are viewing contains questions related to this textbook.
Chapter 2 / Exercise 19
Human Heredity: Principles and Issues
Cummings
Expert Verified
1. In tomatoes, tall is dominant and short is recessive. Red fruit is dominant and yellow fruit is recessive. Choose a key for height:T= tall, t= shortfor color of fruit:R = red, r = yellowWhat is the genotype of a plant heterozygous for both traits?TtRr What are the possible gametes for this plant?
2. Using words, what are the likely parental genotypes if the results of a two-trait problemare 1:1:1:1 among the offspring?
3. In horses, black (B) and trotting gait (T) are dominant while brown (b) and a pacing gait (t) are recessive. If a black trotter (homozygous for both traits) is mated to a brown pacer , what ratio is expected among the offspring?
4. Two black trotters have a brown pacer offspring. What is the genotype of all horses involved? black trotter parents
5. The phenotypic ratio among the offspring for two corn plants producing purple and smooth kernels is 9:3:3:1. (See p, 110 for the key) a. What is the genotype of the parental plants?
6. Which matings could produce at least some fruit flies heterozygous in both traits? Write yes or no beside each. (You do not need a key.)
7. State two new crosses that could not produce fruit flies heterozygous in both traits.