Review Session 1 Key

Review Session 1 Key - Review session problems for Oct. 2...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
1 Review session problems for Oct. 2 2011 Two lectures covered by these problems, topics = monohybrid crosses, di/trihybrid crosses, use of laws of probability to predict ratios/frequencies rather than Punnett squares, use of Chi squared to test how well data fits Mendelian ratios 1. In nature, fruits of the plant Plectritis congesta can be wingless or winged (see below) – both types are quite common. To try to understand the genetic control of this trait, you collect 3 winged fruits and 2 wingless fruits, grow plants from them, and do some controlled crosses with these plants. The results are as follows: CROSS: PROGENY FRUIT: ________ # WINGED # WINGLESS winged #1 selfed 91 0 winged #2 selfed 90 32 wingless #1 selfed 0 85 wingless #2 selfed 0 92 winged #1 x wingless #1 161 0 winged #2 x wingless #2 29 31 winged #2 x winged #3 44 0 a. How many genes appear to be involved in determining whether fruits are winged or wingless? One b. Which is the dominant trait, winged or wingless (2 pts)? Winged c. Given the results in the table, what phenotypic classes do you expect to find among the selfed progeny of winged #3, and in what proportions (4 pts)? Results of cross between winged #2 x winged #3 tell you that winged #3 must be homozygous for the dominant allele, therefore expect all winged.
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
2 2. Certain varieties of flax (the plant) show different resistances to specific races of the fungus called flax rust. Flax variety 770B is resistant to rust race 22 but susceptible to race 24, whereas flax variety Bombay is resistant to rust race 24 but susceptible to race 22 (both varieties are true breeding for these traits). When 770B is crossed to Bombay, the F1
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 4

Review Session 1 Key - Review session problems for Oct. 2...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online