Hands-on labs, inc. Version 42-0063-00-01
LAB REPORT
PHOTOS – Include these digital photo with your lab report, either as a separate attachment to an e-mail or paste into your document.
1. Photo #1 –Take a photo of the seedlings AFTER they have sprouted – close enough to the petri dish to see the little seedlings, even if they are not clear enough to count in the photo.
Exercise 1: observing a Monohybrid Cross
Data Table 1: Punnett square
Father ( g g ) × Mother ( g g )
Father (♂)
gametes g g
Mother (♀)
Data Table 2: Seedling data
Seedling Color
green yellow Total
Number of
Seedlings
Percentage of
Total
Questions
A. What are the predicted ratios of the phenotypes in the plants?
B. What was the total number of seeds that germinated?
C. What are the actual ratios of the phenotypes displayed in the tobacco plants?
D. Explain why it may be important to collect data from a larger population.
E. If all yellow seedlings were removed from the population, would the next generation still have a chance at displaying the yellow allele? Explain.
F. Estimate the number of generations required before the yellow alleles were eliminated from the population. Explain.
G. Would a cross between a homozygous and a heterozygous parent show the same ratios?
Explain.
Exercise 2: Simple Chi-square Analysis
OMIT
Exercise 3: Dihybrid Crossing with Corn
Observations
Data Table 5: Corn kernel data
Number of
Kernels
Kernel Percentage (Divide count by total, then multiply by 100)
Kernel Coloration
Purple
yellow
Total
Kernel Texture
Smooth
Wrinkled
Total
Data Table 6: Punnet square for dihybrid cross.
Parent gametes ♂
PS
Ps
pS
ps
P a r e n t gametes ♀
PS
Ps
pS
ps
Questions
A. Percent of expected Purple, smooth kernels B. Percent of expected Purple, wrinkled kernels C. Percent of expected