SC 135 - Fourth Exam 2011


Links connect to relevant parts of the online book.




On the line to the left, place the letter of the choice that best  answers the question.

Three Points Each.                              NOTE:  "e" answers are never the correct answer.



1.    It appears the snowball period was directly needed for what step?

_______                a.  Complex plants                           b.  Cellular life

c.  Complex animals                        d.  Modern humans

e.  The evolution of mittens





2.   Electron transport chains produce a lot of

_______                     a.  ATP                       b.  Enzymes                           c.  Sugars

                        d.  Cells                                  e.  Noise





3.   What are usually coupled in coupled reactions?

_______                a.  Hot and cold                                b.  Metabolic and waste

c.  Enzyme and inhibited                   d.  Exergonic and endergonic

e.  Not sure, but I don't want to see their hooking-up websites





4.   The first major stage of a mass extinction affects the

_______                a.  Top predators                              b.  Plants

c.  Decomposers                               d.  Water

e.  Property values





5.   Cofactors are usually

_______                   a.  Enzymes                           b.  ATP                       c.  Minerals

            d.  Vitamins                            e.  Not paid the big bucks





6.   We know the materials in primordial soup because they still exist

_______                a.  Deep in the Earth                                     b.  On other worlds

c.  In stardust                                               d.  All of these

e.  On the original billing receipts





7.    Modern evolutionary theory sees evolution as changes in

_______                a.  Reproduction types            b.  Gene pools                   c.  Classes

d.  Food chains                                 e.  Popular music






8.   The hardest challenge of life on land, the last actually solved by both

animals and plants, involved

_______                a.  Reproduction                   b.  Breathing              c.  Support

d.  Nutrition                           e.  Where to find a good pizza






9.    A layer of rust (iron oxide) in the fossil record is a marker for the

_______                   a.  Asteroid impacts                b.  Rise of photosynthesis

            c.  Ice ages                             d.  Death of plants

                     e.  Great Scrap Iron Age





10.  Which would have specificity?

_______                     a.  Enzymes and receptors              b.  Sugars and starches

                        c.  Anaerobic organisms                  d.  Fossil layers

e.  Is that even really a word?





11.  Molecules in the first complex living systems are thought to have been

_______                a.  Proteins                 b.  Carbohydrates                 c.   DNA

d.  RNA                                  e.  Gooey





12.  Nitrogenous wastes come from

_______                a.  Protein breakdown                      b.  Protein synthesis

c.  Anaerobic respiration                  d.  Cell membranes

e.  Places we don't want to think about




Answer any eight of the following questions for 4 Points Each.
  if you answer more than eight, only the first eight  will be corrected.
You can get partial credit on these answers.


1.   What makes something a vitamin?



2.   Show the basic reaction of aerobic respiration, including any side products.



3.  In a food chain, what ultimately happens to most of the -






4.   What are two different things that happen during glycolysis?


5.   Hardy-Weinberg describes how alleles remain stable in a population if there's no selection or mutation.  What two other things must also be true?


6.   What two different ecosystems are thought to have been the staging areas for the movement of Life onto the land?


7.   The three levels, in order, of a classic food chain -


8.   Two different abilities the first living systems needed to have to start -


9.    Two different abilities that evolving living systems needed eventually but which were not needed at first -


10.  Living things produce three main types of nitrogenous wastes.  What are two?



11.  Living systems appear to break the Second Law of Thermodynamics.  How do they get away with it?




12.   Briefly explain the plant problem.




13.  Explain why a protein may denature when it gets too warm.




14.  Define chemosynthesis.




15.  What are the two main uses that plants have for their starches?






Answer any four of the following questions for Eight Points Each.

Note:  if you answer more than four, only the first four will be corrected.
You can get partial credit on these answers.


1.  What are four different ways that anaerobic organisms impact humans? 
2.   For oxygen debt -

Tissue it

happens in -

Conditions it        

happens during

What is


3.   For each step in the theoretical development of Life on Earth, put them in chronological order, from earliest to latest, 1 - 8 in the boxes to the left.







onto Land















4.   Briefly describe how three different types of reproductive isolation work.  A single term is NOT enough, this needs a short description.




5.   For the main photosynthesis reactions:
Name Exact Materials or Energy Used Exact Materials Produced
6.   Briefly describe the three different ways that enzyme inhibition can work.
7.   Below is a graph showing how enzyme activity, measured through the rate of the reaction catalyzed by the enzyme, reacts to changes in pH (NOT temperature!).  Fill in:  A)  The name given to the pH where the graph peaks; B) Why the graph peaks there;  C) and D) What's happening to the enzyme molecules as the rate drops off (C) below the peak; and (D) above the peak.




 Reaction               C                                                                   D






                                                        Increasing pH C>


Link to Answer Key

BONUS QUESTIONS.  Answer as many as you are able.  Wrong answers will not result in points being lost from the main exam.   You can get partial credit on these answers.


Evolution can happen faster in small populations.  Explain why.  Three Points.




Why are there more described species of beetles when they probably are not actually the biggest group?  Three Points.



The conservation law (First Law of Thermodynamics) used to be 2 laws - what happened to make it become a single law?  Three Points.



Why are so many metabolic products considered multiple-gene traits?  Three Points.



What is a regulatory site?  Three Points.



What ability do cofactors have that enzymes usually do not?  Three Points.



Where would you find most hydrothermal vents today? Three Points.



What part of lipids are fed into respiration?  Three Points.  And why do they contain so much energy?  Three Points.



What is panspermia?  Three Points.



Why exactly are religious explanations for the beginnings of Life not considered scientific?  Three Points.



Plants could never have moved onto land without what symbionts (Two Points), and why? (Three Points)




SC 135 

Michael McDarby





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