BI 173 - First Exam - 2000 - ANSWER KEY
PLEASE NOTE - Multiple choice key has comments after choices.
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.
___B___ 2. The ventral fins of a shark and anterior fins of a squid both serve as stabilizers but
share no real underlying structural features. This makes them
a. Analogous
b. Analogous but not homologous
c. Homologous
d. Homologous but not analogous
e. Equally uninteresting
...by definition, analogous is similar function, homologous
means
sharing structural foundation...
___D___ 3. What very common genetic feature did not affect Mendel's original genetic
experiments due to his choices of studied traits?
a. Mitochondrial recombination
b. Mutation
c. Segregation of alleles
d. Linkage
e. Blaming of parents for how the kids are screwed up
...for whatever reason, he picked traits whose genes are on
different chromosomes (not linked)...
___C___ 4. The early discovery of fossils first presented which "blasphemous" idea?
a. Evolution
b. Giant serpents
c. Extinction
d. Man as just type of animal
e. Ancient fanged Pope
...Nature today is a holdover of a perfect Eden...
___B___5. What occurred during the Cambrian explosion?
a. Virtually all major multicellular organism groups "appeared"
b. Virtually all major animal groups "appeared"
c. Life first appears in the fossil record
d. Life moved onto the land
e. Ummm...."Boom?".....
...right out of the notes...
___C___6. The component parts of a colonial organism, unlike a regular multicellular organism,
a. Are themselves single cells
b. Can work together
c. Can survive independently
d. Do not share nutrients
e. Occasionally fight a revolutionary war against the oppressive individual
...but don't usually do that - the colony is in many ways
like the multicellular organism...
___A___7. Which is the pattern for a gene code?
a. Three bases code for each amino acid
b. Three amino acids code for each base
c. The sequence pattern changes depending upon the type of coded molecule
d. Each base codes for each amino acid
e. How does a gene catch a code?
...it's a basic knowledge sort of thing...
___C___8. Thomas Malthus influenced evolutionary theories with his ideas about
a. Evolution of new species
b. The age of the earth
c. Control of populations
d. Inheritance of acquired characteristics
e. His game show, "Who wants to be an advanced organism"
...Darwin's ideas are strongly influenced...
___D___9. In a typical nonpolluted lake, phosphate is rare, but wherever it is available, it will move
into living cells that themselves have a much higher concentration than the water, through which process?
a. Osmosis
b. Mediated diffusion
c. Passive transport
d. Active transport
e. Chat room deception
...it's moving "uphill," from low concentration to high...
___A___10. Which is a major function of microtubules?
a. Movement of flagella
b. Membrane-to-membrane contacts
c. Support of microvilli
d. Gene transcription
e. They're parasites on Teletubbies
...just a basic knowledge thing...
___B___11. It now seems likely that the first photosynthetic systems probably arose as a
combination of
a. Chemosynthesis & nutrition processing
b. Chemosynthesis & light sensing
c. Heat absorption and powered movement
d. Nutrition processing & powered movement
e. A vast alien real estate deal
...hydrothermal vents - hot chemicals for chemosynthesis, mild
glow to make light-sensing adaptation logical, sets up
combination for those brought to surface where it could
be
used as light-based synthesis system...
___C____12. The acidity of a solution is measured on a scale for the proportion of
a. Water
b. Hydroxide
c. Hydrogen
d. Electrons
e. Nasty biting things
...pH = proportion of nHydrogen...
___C___13. What sort of focusing lens is found in an electron microscope?
a. Glass
b. Liquid crystal
c. Magnets
d. Reflective metal
e. Expensive
...it's the only thing that can bend an electron beam...
____B__14. Which is an evolutionary disadvantage associated with sexual reproduction?
a. It always requires a partner
b. A particularly advantageous set of alleles cannot be passed on exactly
c. Not enough variation
d. Mutations are particularly damaging
e. It produces bad reputations
...you can mix good genes but you can't get exact duplicates...
___A___15. In the fluid mosaic model of membrane structure,
a. The fluid is largely lipid, the mosaic mostly protein
b. The fluid is inside the membrane, the mosaic is on the surface
c. The fluid is water, the mosaic dissolved materials
d. The fluid represents permeability, the mosaic impermeability
e. The fluid models work for Sears, the mosaic models for Victoria's Secret
...a basic biology concept...
SHORT ANSWER.
Pick EIGHT Questions to answer in the spaces provided.
NOTE: if you answer MORE than eight, only the first eight will be corrected.
Five Points each. Partial credit is possible.
1. What are two features most well-known organisms share that make them unlikely to have a smooth, progressive fossil record?
...they don't live in water and they don't have enough connected hard parts...| A low number of chromosomes:
...little variety in offspring... |
A high number of chromosomes: ...more problems during replication & cell division... |
...during metaphase of Meiosis I, homologous chromosomes are brought
together and can swap pieces
4. What aspects of artificial selection made it part of Darwin's steps toward developing his
Theory of Evolution by Natural Selection?
...types could be changed over time, and selection of traits was
part of the changing process
5. There are two very different ways that scientific predictions can be properly tested. What
are they?
...controlled experiments..................systematic observations of
the real world...
6. What are two different classes of molecules used in comparative biochemistry?
...could be metabolic molecules, proteins, DNA (RNA would be same class
as DNA)
7. Briefly explain how genetic redundancy can be evolutionarily advantageous.
...genes can be changed without affecting their original function...
8. What is the function of a nucleolus?
...it holds materials for RNA and ribosome production...
9. There are two major precepts of geologic uniformitarianism. What are they?
...the world of the distant past was not all that different from the
world today...any changes that have occurred have been very slow...
10. What are two aspects of the chemistry of living things that make them distinct from the
processes of "nonlife?"
...it involves increased organization, lessened entropy...it uses DNA as
a basis for coding information...
11. Why are embryological similarities between groups slower to disappear than similarities at
the adult stage?
...the earlier a change appears during life, the more dramatic its
eventual effects tend to be, so the effects are more likely to produce
major bad changes...
12. What is the inferred function in a cell full of Golgi bodies?
...since Golgi is involved in packaging materials for release, cells
with lots of it are in the secretion business...
13. What are two ways that the process of meiosis is distinctly different from the process of
mitosis?
...there are more than two...there are two divisions, producing four
cells (vs 1 & 2)...cells start diploid and wind up haploid (vs
diploid to diploid)...part of the division involves separating
homologous chromosomes (vs this doesn't happen)...it's used to set up
sexual reproduction (vs being a form of asexual)...
14. Why is the concept of primordial soup so important to the heterotroph hypothesis?
...if the first organisms couldn't produce their own "food,"
then food had to be available that had NOT come from living things -
that's the soup...
15. Of the various types of molecular bonds, which one has the least impact in living systems,
and why?
...ionic bonds, which usually disassociate in the water that makes up
all living things...
LONG ANSWER.
Select and answer completely any three of the following questions.
NOTE: if you answer more than three, only the first three will be corrected.
Ten Points Each. Partial credit is possible.
1. What are three different ways that organisms use to determine gender?
|
matched vs unmatched set of chromosomes |
|
pair vs single chromosome |
|
done as response to environmental stimuli |
|
There are several, based upon advancements in genetics, chemistry, and
ecology...
|
|
|
|
|
| Name | One basic use | Another basic use |
|
Carbohydrates |
Energy source | Structure also markers |
|
Proteins |
Generate force; immune molecules; structure; communication | Enzymes; etc |
|
Nucleic Acids |
Hold basic informational codes | Used to convert basic information into proteins |
|
Lipids |
Longterm energy storage; water barriers |
Insulation: hormones |
| CILIA | FLAGELLA |
|
Smaller |
Larger |
|
Always very many on cell |
Rarely more than twelve on cell |
|
Do not have added substructures |
May have several types of added substructures |
|
Individuals with traits best-suited to the changed environment are more likely to live to reproduce. They will make more offspring then those not so well suited, over time. |
|
More offspring in succeeding generations will show the advantageous traits. |
|
Eventually, the basic "type" of the organism becomes changed to the well-adapted form. |
|
The "type" is different enough from the ancestor to be a new species. |
|
|
NO KEY FOR BONUS QUESTIONS.
BONUS QUESTIONS. 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 Three Points each, what traits of living things are not really found in viruses?
Osmosis gets a special designation, but it's really just a type of diffusion. Why is it useful to
consider it separately? Three Points.
Gregor Mendel did his historic work with pea plants. Why did he use that particular organism
for his experiments? Three Points.
What reasons other than scientific study may have led Charles Darwin to spend as much time
ashore during his voyage on the HMS Beagle? Three Points each.
Where did Alfred Russel Wallace do his
work (2 Points), and why was that a good
place to develop a theory of evolution
(Three Points)?
Why is mitochondrial DNA considered a
better research source than nuclear DNA?
Three Points.