Spring 2012 Agriscience
Essay Midterm Exam
Name (print large and clearly):
Date:
Hr:
Directions: Do NOT open this packet until instructed to do so. There should be absolutely NO TALKING during the exam
unless you have raised your hand and have been called on by the instructor. Failure to do so will result in one verbal
warning, and then a failed test grade.
Students should sit on opposite sides of the lab tables for this exam. DO NOT sit together on the same side.
This portion of the exam consists entirely of short answer responses. Fully use the space given! The more you write, the
more likely you are to receive a higher grade. Typically, short answers consist of responses with 3 or more parts. Make
sure that you are fully answering each question – do not leave a part of a question unanswered!
For this exam, choose any 2 of the 3 questions to respond to. If you do more than 2, only the first 2 will be graded.
You may use one and only one 3x5” note card with your own handwritten notes. This notecard must stay on the desk in
front of you at all times.
Tips & Hints
Specific examples are always effective when used properly. Vague statements have little value without examples to
support them. If you make a statement, back it up with an example from class, notes, or a reading if possible.
Do not assume that I know you know – explicitly state what you are trying to say. Vague answers never get full credit.
If a question has multiple parts, label these parts in your response. Clearly indicate what you are responding to.
A guess made with common sense could get you more test points than if you leave an answer blank. NEVER leave a
question unfinished if you can help it.
Use the “what, why, how” format – explain what you are talking about, explain why it is necessary, and talk about how it
happens.
Good Luck!
Question 1: Mr. Kohn is tired of having to turn on the lights at night when he wants a glass of milk. Mr. Kohn knows of
jelly fish that produce proteins that glow in the dark. Explain how Mr. Kohn could create genetically engineered cows
that could produce these glowing proteins in their milk.
Part 1) Begin by describing the process of how a section of DNA such as a gene would become expressed through
transcription and translation into amino acids. Be sure to include the following: DNA, RNA, gene, transcription, mRNA,
helicase, polymerase, translation, rRNA (or ribosome), tRNA, amino acids.
Part 2) Then explain how the amino acids assembled by the ribosome would become a functional, glowing protein and
how the protein “knows” what job to do. Be sure to include or address the following: amino acids, polypeptide, protein,
primary structure, secondary structure, tertiary structure, quaternary structure, the 3 properties of amino acids, shape
of amino acid chains, alpha-helix, beta-sheet, and function of a protein.
Part 3) Finally, explain what impact the glowing milk would have on Mr. Kohn’s body when he drinks his special milk.
Question 2: A puppy is born with a mutation that changes the amino acid sequence and the shape of the protein that
breaks down starch.
Part 1) Explain how a mutation in this puppy’s DNA would affect its a) DNA, b) transcription, c) translation, d) protein
folding, and e) protein function.
Part 2) Imagine this puppy with the mutation grows up and has puppies of its own. If this puppy were heterozygous for
this mutated gene, how would its offspring be affected?
Part 3) The phenotype of this particular dog is not described. Describe how the impact will affect this dog if a) the
mutation were dominant; b) the mutation were recessive; c) the mutation were incompletely dominant.
Question 3: In a breed of chickens called Wolverrinnes, color has an epistatic relationship. These chickens can either be
red, orange, or yellow. A chicken will be red if they are RR or Rr. A chicken will be orange or yellow if they are rr _ _.
While red (RR or Rr) is dominant to both yellow or orange, orange (rrGg or rrGG) is dominant to yellow (rrgg). To
summarize
Red: RR_ _ or Rr _ _
Orange: rrGg or rrGG
Yellow: rrgg
Chicken A with genotype RrGg is crossed with Chicken B with genotype rrgg. Use this information to answer the
questions below.
1) What are the colors of Chicken A and Chicken B?
2) After showing your work in the dihybrid square below, state below how many offspring out of 16 would be red,
how many would be orange, and how many would be yellow (assuming all predicted ratios are followed).