Biology 111: Unit 1February 2000

The review is due Friday February 16th at 9:30am.

This is a closed-book, closed-note review. Once you have read any question your review period has begun. There is no time limit for taking the review. It was designed to be completed in 2 hours.

The questions are yours to keep. This page must be the first page of your answer packet. Fill out the information at the bottom of this sheet and attach this page to the ones containing your answers. The top of each additional page in the packet should contain only your initials and the page number. All answers must be typed and in complete sentences unless otherwise indicated.Any accompanying graphs or figures may be hand-drawn. You may use a calculator but all calculations must be included in order to receive full credit. Brevity is encouraged but be sure to completely answer the question asked.

Any questions about the review should be directed to me at, 894-2889 (o), or 662-9744 (h). Any calls to my home must occur before 9:00pm.

Name: ____________________________________


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My signature indicates that I have completed this review following the Honor Code.

This review was completed in ________hours

Section 1 (Short Answers, parts A-D, 20 pt total)

For each of the terms that follow provide 1) a definition and 2) an example taken from the four main examples of cellular communication discussed in class. Answers must be in complete sentences and should be no more than two (2) sentences in length. (4pt each)

A)Biological membrane


C)Enzyme Cascade


E)Ion Channel

Section 2 (parts A-I, 40pt total)

Clearly, concisely and using complete sentences answer all of the questions for the scenario that follows. You may use a calculator to perform calculations but all work must be shown in order to receive full credit.

Enthralled with the process of glycogenesis you and your lab group have decided to study the following enzymatic process.



A)What is role of an enzyme? What is the enzyme in this reaction? (4pt)

B)What is a polymer? Which component(s) in this reaction is/are polymers? (5pt)

It is your group’s intention to use microtiter plate assays and spectrophotometry to follow the progress of this chemical reaction. You all agree that you must determine the absorption maximum of one component and use the change of absorbance over time to follow the reaction. However, group members disagree over which component should be followed. Joe says you should look at glycogen. Sharon wants to follow glucose. George thinks that glycogen synthase is the component to watch.

C)What is an absorption maximum? (4pt)

D)With which of your lab group members do you agree? (2pt)

E)You convince you group that you are right, set up a reaction and follow the absorbance of the component you named in D. As the reaction progresses will the absorbance increase, decrease, or stay the same? Why? (5pt)

F)This enzymatic reaction was involved in one of the cellular communication examples discussed in class. Using what you know about that example, briefly describe two (2) ways you could inhibit the reaction. Include the names of the molecules/compounds you would add to the reaction mix and why that addition would block the reaction. Answer in no more than 6 sentences (3 per example). (8pt)

During your experimentation you find out that the lab has 3 sources of glycogen synthase. The stock shelf includes bottles containing the following information:



Molecular Weight

Concentration of stock

Bottle 1: Pig glycogen synthase
Bottle 2: Sheep glycogen synthase
Bottle 3: Giraffe glycogen synthase

On your bench you have a sample of the enzyme you used but your group members forgot to write down which kind it was. 

G)What type of experiment can you perform to determine which stock of enzyme you used? Briefly describe how the procedure works and how results from this experiment will determine which glycogen synthase you had been using. (6pt)

Being thorough scientists, you decide to compare reactions containing glycogen synthase isolated from each species. Each reaction requires 10ul of glycogen synthase that has been diluted to 2ug/ul. Gathering up the stock bottles, distilled water, microfuge tubes and pipetmen (w/tips) you prepare your glycogen synthase dilutions.

H)How many microliters of pig glycogen synthase concentrated stock are needed to make 40ul of the 2ug/ul solution? (3pt)

I)You are performing each reaction in triplicate. Calculate the total number of micrograms of sheep glycogen synthase you need. (3pt)


Calculate the molarity of the concentrated stock of giraffe glycogen synthase. (2pt) 


Answer four of the following five questions in clear, concise, complete sentences. Be sure to answer the question asked. Although each can be completely answered in less, include no more than one page for each answer (12pt, 1 1/2 space). (10pt each)

A) What type of molecular is a phosphodiesterase? What role, if any, have phosphodiesterases played in each of the main examples of cellular communication discussed in class? (Be sure to mention each example and to discuss the importance of phosphodiesterases to each type of communication.)

B) Allosteric modulation has played a big role in our examples of cellular communication. Define allosteric modulation and provide, and briefly explain, examples that illustrate how this modulation can be accomplished by both covalent and non-covalent bonding. Each example you provide must come from a different cellular communication pathway.

C) Compare and contrast how ions generate action potentials and how they stimulate cortical granule fusion. Do not discuss the entire pathway. Focus only on the indicated portion. Your discussion must include the kind of ion and any types of transport used (it should include more than that for full credit).

D) Epinephrine was the initial signal in three of our examples of cellular communication. Where is epinephrine produced? How can the same signal cause different cells to do different things? Why would the body ‘want’ to use one signal to trigger three different pathways (why not use 3 signals)? 

E) Where in the cell do you find 1) the ATP-dependent Ca2+ pump and 2) tropomyosin? Given that localization describe, in chemical terms, how a protein like the ATP-dependent Ca2+ pump would differ in amino acid sequence from one like tropomyosin.