SC 139 - First Exam 1998

ANSWER KEY

MULTIPLE CHOICE. 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. Which example fits Lamarck's theory on evolution?
_______                 a. In giraffe ancestors, the taller individuals had more success
                               b. 2-legged movement in kangaroos can be traced back to the offspring
                                              of an ancestor that injured a front leg
                               c. Antibiotics select certain bacteria that can withstand them
                               d. Better-coordinated individuals would be better hunters
                               e. It's not what you know, it's who you pay off

                        2. Of the energy sources available on the very early Earth, which was least
                                              likely to have been used in forming the first living molecules?
_______                 a. Visible sunlight                 b. Heat                 c. UltraViolet
                               d. Radioactivity                     e. Hershey's primordial chocolate

                        3. Sickle-cell anemia can, in a hybrid situation, make someone resistant to
_______                 a. Diarrhea                 b. Cystic fibrosis                 c. Malaria
                               d. Mutations                                 e. Telemarketers

                        4. Fossil bones seem "rocky" because
_______                 a. Minerals have replaced the bone             b. Radiation changes bone
                               c. Drying makes them that way                   d. The bones were like that
                                           e. It'd be silly for them to seem "bullwinkle"

                        5. Which classification system specifically focuses on the appearance of traits?
_______                 a. Systematics                 b. Taxonomy                 c. Speciation
                               d. Cladistics                                 e. Traitor system

                        6. Charles Lyell's ideas of geologic uniformitarianism and the history of the
                                        Earth has affected most theories on evolution. Which aspect of
                                        those theories reflects this?
_______                 a. Real changes have come about through mutations
                               b. Traits acquired through a parent's lifetime are sent on to offspring
                               c. Changes have been very slow and gradual
                               d. All of these come from geologic uniformitarianism
                               e. Terms over 15 letters long should be outlawed

                        7. The fitness of an adaptation is determined by
_______                 a. Evolutionary biologists                    b. Genetic strength
                               c. The current environment                 d. Its mutations
                                                       e. Wild athletic trainers

                        8. The small populations that came across from Asia to North America were
                                        missing some alleles, which remain missing in the current, large
                                        population of Native Americans. This is an example of
_______                 a. Artificial selection                         b. Recombination
                               c. Random mutation                         d. Founder effect
                                           e. Why I don't understand any of this

                        9. Homeogenes are involved with
_______                 a. Basic layout of features                   b. Mutation control
                               c. Reproduction                                 d. Disease resistance
                                           e. Stuff you'd need in the 'hood

                        10. When major fossil discoveries were first made, what immediate implication
                                        challenged the accepted ideas of the time?
_______                 a. Man evolved from apes                 b. Living things had become extinct
                               c. Natural selection was at work        d. Genes had mutated
                                           e. We'll all wind up mounted in museums

                        11. The process that gave us dachshunds and Siberian huskies is
_______                 a. Natural selection                 b. Sexual selection
                               c. Artificial selection                d. Adaptive radiation
                                      e. Some pretty whacked-out dog breeders

                        12. Darwin's finches, several different species that probably branched out from
                                        a single starting group of mainland finches, are an example of
_______                 a. Adaptive radiation                               b. Hybrid vigor
                               c. Type species or ecospecies                 d. Sexual selection
                               e. The sort of strange little creatures scientists get all gooey about

                        13. The organic molecules in Primordial Soup came from
_______                 a. Interstellar dust         b. Plants        c. Animals         d. Bacteria
                                       e. One of those weird Flintstones' companies

                        14. When a population gets near extinction but recovers, its evolution may show
_______                 a. A higher mutation rate                 b. Niche speciation
                               c. A bottleneck effect                      d. Hybrid vigor
                                                   e. Extreme nervousness

                        15. What allows the development of new traits without the loss of the old ones?
_______                 a. Reproduction         b. Genetic drift        c. Redundancy 
                               d. Hybrid vigor                e. Very well drawn-up contracts

SHORT ANSWER.  

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 ways that the age of a layer of fossils can be estimated?

2. It seems most likely that evolution works at both a gradual and punctuated pace. Why?

3. What are type species, also known as ecospecies?

4. What is an allele?

5. What is the currently-accepted definition of a species?

6. Explain why both parts should be true: large populations have more evolutionary potential, but smaller populations probably evolve faster.

7. What are two types of large organic molecules that could have been the first living things?

8. Why does evolution tend to "leave alone" processes like embryo development?

9. Briefly explain what is meant by the biological term recombination.

10. Darwin was aware, before he left on the Beagle, of many ideas and processes that helped shape his theory of natural selection while he traveled the world. What are two different such ideas?

11. Most mutations are either neutral or harmful. Why?

12. Put these in order, smallest to largest: Class, Family, Genus, Kingdom, Order, Phylum, Species.

1.	2.	3.	4.
5.	6.	7.	XXXXXXXXXXX

13. To have the best chance of becoming a fossil, what must happen to an organism just after it dies? (Or, how are most fossils formed?)

14. What are two different types of molecules compared in comparative biochemistry?

15. What did the fossil-holding mineral amber start out as?

16. Translate to more modern, understandable language: "Ontogeny recapitulates phylogeny."

LONG ANSWER. 

Answer any three of the following questions for Eight Points Each.
Note: if you answer more than three, only the first three will be corrected.

You can get partial credit on these answers.

1. According to the Hardy-Weinberg Law, a rare allele stays at its starting proportion in a population if what four items are true? (There's more than 4.)

2. Describe - don't just name! - four basically different types of isolation that can lead to the development of new species.

3. For each type of reproduction, give the requested information.

4. Given that traits vary in a population, some variations can give advantages, and more offspring are produced than can survive to reproduce, what points did Darwin propose for his Theory of Evolution by Natural Selection? Make sure you cover selection, inheritance, and speciation.

6. For four of the five Kingdoms given in the textbook, name the Kingdom and give the trait or combination of traits that make species in that Kingdom absolutely different from species in the other four Kingdoms.

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.

For One Point Each, give, in order, the sequence of places visited on Darwin's voyage on the HMS Beagle.

Darwin formulated his theories on evolution long before he published them. Why did he finally publish them? Four Points.

What geographic event in our hemisphere is now thought to have produced an environmental change leading to the evolution of humans in Africa or Asia? Four Points.

What did the Danish study of relatives of schizophrenics discover? Four Points.

A recent fossil discovery was of a dinosaur predator and prey, locked in combat. How did they die? Three Points.

What is more and more often becoming true of "vestigial organs?" Three Points.

What role might silicate clays have played in the beginnings of Life on Earth? Four Points.