In-class Exercise Biology 201
Discussion Date: During lecture on 5/13/08
DIRECTIONS:
In your groups discuss the following questions and be prepared to share your conclusions with the
rest of the class. You may wish to write down some notes.
1. Why do you think that some cells like neurons and muscle cells remain permanently in G0? What are the possible
benefits and consequences in unlocking their G0 stasis?
2. Microtubules are polar structures in that one end (called the “+” end) polymerizes and depolymerizes at a much
higher rate than the other end (the “-” end). Which end do you think is the “+” and which is the “-”?
3. Hundreds of millions of dollars are spent each year in the search for effective treatments for cancer; far less
money is spent on preventing cancer. Why do you think this is true?
4. Many species can reproduce either asexually or sexually. It is often when the environment changes in some way
that is unfavorable to an existing population that the organisms begin to reproduce sexually. Speculate about the
evolutionary significance of this switch from asexual to sexual reproduction.
In-class Exercise Biology 201
Due Date: During lecture on 5/15/08
DIRECTIONS: These questions were based on Mendel lecture.
1. Why didn’t the F1 generation produce a mix of white-purple flower?
2. Why did the white flower reappear in F2 generation?
3. Make a prediction as to what offspring will be produced from the following matings:
a. White flower with White flower
b. Heterozygous with Homozygous recessive
c. Purple flower with White flower
4. Is the family pedigree showing a dominant or recessive trait? Explain. What are the genotypes of Ann, Arlene,
Alan and Christopher? What are the chances of Tom and Sandra producing a child with the trait?
Biology 201
Discussion Date: on 5/20/08
DIRECTIONS: These questions are to be used as group discussion. On a single sheet of paper, write down your
group members and the answer to the following questions. They may be used as test questions on exams.
1. In humans hair texture is the result of multiple alleles. Kinky hair dominates over all other types; curly dominates
over wavy and straight; and wavy dominates over straight. A wavy haired male (who has a mother with straight
hair) marries a kinky haired women (who has a father that is homozygous for curly hair). What types of hair can
their children have?
2. In an arrowhead plant, leaf color and shape are controlled by two linked genes. Wild type leaves are green and
pointed while mutant types are white and round. A plant heterozygous for both genes is crossed with a
homozygous recessive plant for both genes and the following offspring were produced: 40 white round, 38 green
pointed, 10 white pointed, and 12 green round. What is the recombinant frequency and distance between the gene
for color and shape?
3. The recombinant frequency for linked genes, all found on the same chromosome are given. Create a linkage map
for these genes, showing the map unit distance between loci.
a) j, k 12%
b) j, m 9%
c) k, l 6%
d) l, m 15%