Lab 3 (Mitosis and meiosis)
1. List the cell cycle and describe what happens to the chromosomal material in each step.
A)
B)
C)
D)
E)
2. In which phase do cells spend most of their time?_______________
3. What is crossing over?
4. Under a microscope you notice that about 33% of the asci show crossover. Calculate the
number of mapping units.
__________
5. Draw a pair of chromosomes in MI and MII, and show how you would get a 2:2:2:2
arrangement of ascospores by crossing over.
Lab 4 (Plant pigments and photosynthesis)
1. How does chromatography work?
2. Using the table below calculate the Rf values for the pigments. (The solvent front moved
100 mm.)
Band #
1
2
3
4
Distance (mm)
10
35
42
66
Rf value
3. Some chloroplasts are collected. Half of them are boiled and the other half are left
unboiled. Half of each of these collections are then placed into either dark or lighted
situations. They are allowed to incubate and grow, and then they are placed into a
spectrophotometer to measure the absorbance. Using the table below, estimate
absorbance numbers that may go into the empty cells.
Cuvette
unboiled/dark
unboiled/light
boiled/light
boiled/dark
no chloroplasts
(control)
0
10
4. Plot the percent transmittance of your projected results.
20
30