BI 171  - Third Exam  - 2011

Each question's number is linked to the relevant part of the online book, if possible (some questions relate to multiple sections). 



Multiple Choice

Place the letter of the choice that best answers the question on the line to the left. 

Two Points Each.   NOTE: “e” answers are never the correct answer. 



_______ 1.    In a Q10, the “10” represents

                        a.   The change in reaction rate                      b.  A change in concentration

                        c.   A change in temperature                          d.  Amount of reactants

                e.  Some number between 9 and 11



_______ 2.   The function of histones can be described as

                        a.  tRNA processors                b.  mRNA processors              c.  Enzymes inhibitors

                        d.  DNA spools                                   e.  The notes he can hit



_______ 3.    A cell plate is

                        a.  The line of chromosomes during mitosis

                        b.  The beginning of a new cell wall

                        c.  The part of the DNA code that determines basic cell structure

                        d.  The functional part of the spindle

                        e.   A cute name used in nanobaseball



_______ 4.   Unlike prosthetic groups, cofactors are

                        a.  Attached temporarily                                 b.  Organic molecules

                        c.  Not usually associated with minerals         d.  Sometimes considered vitamins

                                                            e.  Much, much cuter



_______5.    The purpose of rough endoplasmic reticulum can be compared to

                        a.  Building a factory next to a major highway

                        b.  Scraping old paint off a wood surface

                        c.  Putting mail in an envelope to send it far away

                        d.  Sticking a post-it note to the refrigerator

                        e.  Ripping your face off and chewing on it




_______6.     A high chromosome number can be bad because it may produce

                        a.  All sorts of different mutations

                        b.  Very limited variation in offspring

                        c.  Problems during cell division

                        d.  All of these

                        e.  Is this some sort of PSA against being high?



_______7.    When does the nuclear envelope disappear?

                        a.  Metaphase                          b.  Telophase                           c.  Prophase

                        d.  Interphase                          e.   Magicphase




_______8.    A red blood cell in a hypertonic solution should

                        a.  Shrink and crinkle          b.  Stay the same             c.  Crawl quickly away

                        d.  Swell up and pop                           e.  Threaten to sue




_______9.    If a moving cell projection has a type of comb attached to it, it is probably a

                        a.  Cell wall                       b.  Exoplasmic reticulum               c.  Cilium

                        d.  Flagellum                           e.  Very hairy cell




_______10.    In order for a tumor to keep growing, which gene needs to be activated?

                        a.  Enzyme inhibitor                            b.   Telomerase

                        c.  Apoptosis initiator                          d.   Growth hormone

                                                e.  The Cheetos gene




_______11.   Glycocalyx is most likely to be

                        a.  In the nuclear envelope                  b.  Driving cilia

                        c.  Cell markers                                   d.  Inside the cell membrane itself

                                      e.  The latest flavor of Red Bull




_______12.   Setting a piece of paper on fire represents

                        a.  An endergonic reaction                              b.  A rheothermic reaction

                        c.  A rheogonic reaction                                  d.  An exergonic reaction

                                    e. Something you’re not allowed  to do during an exam





_______13.   Accumulating point mutations are used in

                        a.  Molecular clocks                b.  Hardy-Weinberg flotation                 c.  Qalleles

                        d.  Telomere degradation                                e.  Online game scoring





_______14.   Which term particularly describes a change in a protein molecule’s shape?

                        a.  Charge shifts                      b.  Allosteric                            c.  Orbital shifts

                        d.  Plasticity                                        e.  Squeezy - stretchy




_______15.   The glycerol in membrane phospholipids is attached to

                        a.  3 phosphates

                        b.  1 lipid and 2 phosphates

                        c.  1 phosphate and 2 fatty acids

                        d.  A phosphate, a lipid, and a cholesterol

                        e.  I’m thinking 3 things…




_______16.  If 3 reactants combine to make two products, what is likely to be the limiting

factor for the reaction?

                        a.  The most stable product                             b.  The most stable reactant

                        c.  Any single product                                     d.  Any single reactant

                                                e.  What’s allowed in their contract




_______17.   Which should have hydrophobic domains?

                        a.  Transmembrane proteins                b.  Catalysts                c.  Plasmids

                        d.  Cytoplasm                                                  e.  World of Warcraft




_______18.   When a cell’s own molecules need to be recycled, they are moved to

                        a.  Contractile vacuoles                       b.  Peroxisomes                       c.  Lysosomes

                        d.  Central vacuoles                                        e.  Little blue organelles



Short Answer.   


Pick NINE questions to answer in the spaces provided.

NOTE: if you answer MORE than nine, only the first nine will be corrected. 

Four Points each.   Partial credit is possible.

1.        What are two different organelles found in both eukaryotes and prokaryotes?


2.   What does MTOC stand for?


3.   During what 3 cell cycle stages can cytokinesis happen?


4.   What are two different functions of a centromere?


5.   Name two different enzymes that are active during DNA replication.


6.    Using this DNA code and the chart, give the coded amino acid sequence.

Starting       ___________________________________________________________________________________

Strand         T A C  C  G  T  A  G  T  A  A  A  T  A  T  G  T  G  T  T  G  C  G  C  A  T  T



7.   What are two different ways that fresh-water organisms prevent osmotic damage?



8.    Generally, why does the reaction rate drop off above an enzyme’s optimum temperature?




9.   What is a likely purpose of a cell if it have lots of -



10.  For the Fluid Mosaic Model, explain which part is -





11.  What is one way that genes are arranged differently on a prokaryote chromosome, compared to a eukaryote chromosome?



12.   Of insertion or substitution, which is the

More dangerous point mutation?




13.  The two organelles most associated with the endosymbiosis theory -

14.  Briefly explain how position effect works.


15.   Confining a reaction will make it reach dynamic equilibrium faster.  Why?




16.  Explain why Okazaki fragments exist.



17.  Briefly describe two ways that making new cells works in prokaryotes differently than in eukaryotes.





Long Answer.  


Select and answer completely any four of the following questions.

Note:  if you answer more than four, only the first four will be corrected.

Seven Points Each.  Partial credit is possible.


1.   Briefly describe four ways that flux can be increased through a barrier.




2.  In the graph below of Michaelis-Menten Kinetics, explain why the curve is doing what it’s doing at each marked point, in terms of the enzyme molecules at work.










     V                                      __________________________


                                     Substrate Concentration (as Enzymes remain constant) ---->

3.   For enzyme activity in different pH environments, briefly explain why the rate drops off

below the


Optimum pH?


above the


Optimum pH?


4.   For the three components of cytoskeleton, name the component and give one situation other than structure in which that component would be active.



5.   Give the functions (names are NOT enough) of three different membrane protein types.




5.   Two different things that happen during transcription in a cell.

Two different things that happen during translation in a cell.


6.  Fill in the arrow-headed labels on this drawing of eukaryote cell structures.







7.   Briefly describe three different ways that enzymes can be inhibited.  









Answer as many or as few as you wish.  You can't lose points on the rest of the exam by getting these wrong.  Partial credit is possible.


For Two Points Each, what are some actual functions of what was once called “junk DNA”?




In what way are plasmids used commercially?  Three Points.




What’s odd about the terms introns and exons?  Three Points.




Enzyme turnover numbers are usually in what number range?  Three Points.



Why does a high affinity lead to a low Km?  Three Points.




What cell structure appears to have no official name?  Three Points.



When does a cell generally “decide” itself to go through apoptosis?  Three Points.



 What is 9 + 2? (No, this is not a math problem)  Three Points.




What settings did the remote controls for the imaginary dragonflies have?  One Point Each.




What tissues in humans are pretty much permanently in interphase?  Two Points Each.





BI 171



Hit Counter