Directions: You may talk to others in the class, but you should come up with your
own, independent answers. Plagiarism will not be tolerated!
1. In the mythological zoo, the curator keeps unicorns in pens labeled
"homozygous dominant", "homozygous recessive" and "heterozygous" in
reference to the horn-gene "H" that is responsible for producing the horn and is
dominant to the "h" allele of the gene in which no horn is produced. (Males and
females in each pen are of course kept separated.)
One windy day, the “homozygous dominant” and “heterozygous” signs
were blown off the fence of the respective pens. You are assigned to determine
which pen contains the homozygous dominant unicorns and which contains the
heterozygous unicorns. Assume that you may allow any pair of unicorns to mate
and that they will mate for life and produce as many offspring as they have the
energy to produce! After all, this is a magical world!
Using Punnett Squares, label all genotypes and phenotypes of the mated
unicorns as well as all the potential genotypes and phenotypes of their offspring.
2. Recall that the gene for hemophilia is on the "X chromosome". Using your
superior knowledge of genetics (& some Punnett Squares), show how Queen
Victoria (who did not have hemophilia) could: (1) have a daughter and a son
without hemophilia and (2) have a grandson with hemophilia. (Recall that Prince
Albert-Victoria's husband-and all the spouses of their children did not have
hemophilia or any genes for it!)
3. Flowers have sex too! Compare sexual reproduction in a flowering plant to
that of two alley cats by listing the names of gametes each species forms and
describing the events leading to the gametes' formations.
4. A hospital technician friend gives you a tube filled with a solution labeled
"digestive enzymes of the human stomach". From your knowledge of human
digestive physiology and the stomach, what would you hypothesize are the
optimal conditions (in terms of temperature and pH) for these enzymes to
perform their proper function? Design a controlled experiment to prove this,
using the resources available in 301 LSE. Hint: Make a table that outlines your
experiment by listing: (1) the values of the independent (or manipulated)
variables and (2) the predicted results (i.e. digestion or non-digestion).
This is an example of the table:
Independent variable:
Predicted Result:
5. It's exam week and you haven't been sleeping or eating normally. You awake
at 6:30 am every morning with a migraine headache. Develop a hypothesis to
explain the cause of your headaches and design a good experiment to confirm
(or reject) your hypothesis.
6. Compare and contrast enzymes with other generic forms of proteins. What
are the two basic characteristics common to all enzymes? Describe where you
might find the different forms of proteins in a human body and give pertinent
examples.
7. Diagram the location and functions of the different chambers into which the
human heart is divided. Using blue and red colors, show the flow of blood into
and out of each chamber. Identify the sources and destinations of the blood
supply for each chamber. Why is the human heart described as a "double
pump"?
8. During the EKG exercise, you measured your heart's electrical activity (as
transmitted through your skin). What is the origin and importance of electrical
signals produced by your heart? What happens to those electrical signals during
a heart attack? Why?
9. The below is a pedigree tracing a recessive, non-X-linked, trait called
attached earlobes. The squares refer to males and the circles refer to females.
AE denotes attaced earlobes and FE denotes free earlobes. Is there an error in
the pedigree? If so, where is it? And explain why it is an error.
10. If you’re are the product of the sexual union between your parents, then
explain why you do not look identical to your same-sex siblings. Why is there
phenotypic variation among your same-sex siblings? (hint: think meiosis)