SC 139 - Second Exam 2003



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.

Links on Numbers go to relevant passages in the online textbook.


1.  The main concept of the Gaia Hypothesis is that

_______      a. Life has disappeared and reappeared on Earth several times
                     b. Life was originally a type of replicating clay
                     c. Life was the result of Special Creation
                     d. Life stabilizes the global environment
                     e. One should use vowels more than consonants


2. For a long time, biological theories about the origin of Life on Earth from starting 
were hard to produce because it was thought that the first 
                            major step would have to produce

_______      a. Plants         b. Animals        c. Dinosaurs         d. Vertebrates
                             e. A story whose movie rights would bring in big bucks


3. Which relies on fungal symbionts to live?

_______      a. Algae         b. Insects         c. Bacteria          d. Land plants         e. Politicians


4. The first "living" molecule systems were most probably what type of molecules?

_______      a. Protein         b. DNA         c. RNA        d. Water         e. Squiggly.


5. Most genetic mutations produce what sort of effects?

_______      a. None or minimal             b. Bad - diseases            c. Good - improvements 
                    d. None of these                              e. Weird laser effects


6. Which relates to ecospecies?

_______      a. Parts of a food chain            b. Same functions, different locations
                     c. Close relatives                        d. Evolutionary partners
                                 e. If itís slimy: "Eeek! A species!"


7. What is the function of a chloroplast?

_______      a. Photosynthesis                 b. Digestion            c. Water absorption 
                    d. Aerobic respiration   
          e. Producing complete confusion in students


8. What was the source of the organic materials in primordial soup?

_______      a. First cells                 b. First plants                c. Space dust
                    d. All of these            e. Well, was it a condensed soup, or more of a stew-?


9. In todayís world, which is true?

_______      a. Heterotrophs are the base of the food chain
                    b. Both heterotrophs and autotrophs are the base of the food chain
                    c. Autotrophs are the base of the food chain
                    d. Primordial soup is the base of the food chain
                    e. Hey, as long as I get fed, I donít care which link I am


10. Which are a typical feature of eukaryotes but not prokaryotes?

_______      a. Fungus symbionts                         b. Membrane chambers
                     c. Reproduction                                d. DNA
                     e. Ummm, how come the answer I want isnít here...?


11. When a mutation produces an extra copy of a gene that can be used for 
                            a new purpose while the "oldí gene keeps producing its original 
                            protein, this is called

_______      a. Redundancy                 b. Replication                c. Genetic drift 
                    d. Adaptive duplication                  e. Xeroxification


12. When primordial soup molecules went through chemical evolution, what did they compete for?

_______      a. Protection from parasites             b. Space              c. Water 
                    d. Raw materials   
                     e. A chance to sing on American Idol



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

1.  What are two different types of molecules whose sequences are compared when biologists are trying to determine evolutionary relationships between species?



2. Define sexual selection in evolutionary terms.



3. The first photosynthesis systems were most likely a combined form of which two pre-existing systems?



4. What were most likely the "staging areas" from which animals evolved into land forms?



5. Briefly explain the endosymbiont theory.



6. What is the advantage of a low chromosome number?



7.  During the era of primordial soup, what are two different energy sources that could have been used to construct complex molecules?



8. What sort of material would have formed the first "membranes" of the first protocells?



9.  Briefly explain panspermia.



10.  Define alternation of generations without using the words "alternate" or "generations."



11. Give two different types of examples of epigenetic traits.



12. What is meant by chromosome linkage?



13. Briefly explain what happens to bring about a founder effect.



14.  What are two ways that the primordial soup Earth environment was significantly different than the Earth today?




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. Describe (donít just give a one-word label!) four different types of isolation that can lead to evolution of different species from the same ancestral group.







2. Answer the following about asexual reproduction -

Definition -


Disadvantage, compared

to sexual reproduction -

Adaptation that "balances

out" the disadvantage -

3.  Describe four different features about the land environment that would have presented major challenges to organisms evolving from water ecosystems to land.









4. What are four conditions, according to the Hardy-Weinberg Law, under which the allele frequencies in a population will stay the same?









5.  According to the heterotroph hypothesis, what is the most likely order in which the following things appeared on Earth? Number from 1 to 8 to the left of the terms.




onto Land





6. The very first living things would have needed some basic traits to be considered "living...

Two traits needed in the
early molecule systems




Two traits that werenít
needed at first, but had
to appear before long




Answer Key


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.

If a biologist is trying to determine the gender (male or female) of an organism or structure, animal, plant, fungus, whatever, what particular feature has to be checked? Three Points.



What is it about sharks that makes them very resistant to cancer? Three Points.



The northern end of the original mountain chain that includes the Adirondacks ends where today? Three Points.



What scientist is considered the "father" of biogeography? Three Points.



Some of the worldís oldest fossils are found locally - where? Three Points.



The spread of photosynthetic organisms across the oceans left what sort of mark in the fossil record? Three Points



During the Age of Dinosaurs, the dinosaur-like animals that lived in the oceans were really what sort of reptiles? Three Points.



Which groups are often thought of as the last surviving dinosaurs? Three Points.


Michael McDarby.

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