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SC 139 - Second Exam 2000
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. The organic material that acted as "food" in the primordial soup most
likely
originated from
___C__ a. The first heterotrophs
b. The first autotrophs
c. The space material that the Earth formed from
d. Decomposition of dead cells
e. Some really desperate food conglomerate
...it had to be there first, before any of the other stuff
arose...
2. The endosymbiosis (or endosymbiont) theory is used to explain
___B___ a. Plant-insect adaptations
b. Eukaryote cell components
c. Movement of plants to land
d. Alternations of generations
e. Why gas prices keep going up
...how mitochondria and chloroplasts arose in cells - picked up as food,
kept on as helpers, eventually became parts / components...
3. Which is the sporophyte part of a dandelion?
___A___ a. Almost the whole plant
b. Parts of the flower
c. Only parts of the seeds
d. The root system
e. Are there labels anywhere?
...any modern (even not-so-modern) plant is sporophyte except for the
reproductive parts, which are gametophytes...
4. The appearance of wormlike shape in several unrelated groups of
burrowing animals is an example of
___D___ a. Asexual reproduction
b. Divergent evolution
c. Sexual reproduction
d. Convergent evolution
e. How you just can't keep a good shape out of the line-up
...it's kind of a reworking of the definition as an example...
5. It's quite likely that a clump of ferns are all products of the same
___D___ a. Cone
b. Seed
c. Flower
d. Rhizome
e. Sad liquor and tranquilizers evening
...no other choice is found in ferns...
6. The main purpose of a fruit involves
___C___ a. Feeding seeds
b. Feeding hosts
c. Spreading seeds
d. Attracting pollinators
e. Creating stereotypes
...if you go with your preconceived notions here, you're wrong...
7. Whale flippers and bat wings have the same basic bone pattern. They are
a. Analogous but not homologous
b. Homologous but not analogous
___B___ c. Both analogous and homologous
d. Neither analogous nor homologous
e. Rarely used as ingredients on The Food Network
...built of the same parts but doing different things...
8. Which is a bryophyte?
___C___ a. Pine tree
b. Fern c. Moss
d. Apple tree e. Regis Philbin
...right out of the notes...
9. Which traits are used to divide up the major plant groups?
___A___ a. Tube systems and seeds
b. Leaf and root types
c. Ecosystem they're found in
d. Whether sexual or asexual
e. Edible or decorative
...vascular / nonvascular and gymnosperm (naked seeds) / angiosperm
10. Which is a female part of a flower?
__D____ a. Stamen
b. Sorus
c. Anther
d. Pistil
e. That seems kind of personal
...out of the notes; a & c are male, b is a fern spore-maker
11. The early, basic layout of an embryo is generally controlled by
___B___ a. Symbiotic organisms
b. Homeogenes
c. The "molecular clock"
d. Genetic redundancy
e. An angel with a rough schematic and a pair of dice
...out of the notes...
12. Classification and evolution dependent on the "appearance" of certain
defining traits is called
___D___ a. Taxonomy
b. Neo-Darwinism c. Systematics
d. Cladistics
e. Traityness
...out of the notes...
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. Define alternation of generations.
...a life cycle that always includes both an asexual phase and a sexual
phase...
2. Name four major groups of organisms that are considered "land" groups.
...could be plants, insects, arachnids, amphibians, reptiles, dinosaurs,
birds, mammals...
3. Why is it reasonable for evolution to be both gradual and punctuated?
...evolution patterns follow the pattern of changes in the environment,
which can be both sudeen and dramatic or long and gradual...
4. Two-part question, looking for definitions, not examples:
According to old ideas, what is a vestigial structure?
Some structure that is
being "lost" because it has no purpose, but isn't
"gone" yet.
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According to new ideas, what is a vestigial structure?
A structure that is
serving some subtle purpose we haven't figured out yet.
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5. Briefly give the basic premise of the Gaia Hypothesis.
...that all of the living things on Earth help to stabilize the
environment, acting like a sort of thermostat...
6. Define diploid.
...having two matched sets of chromosomes...
7. When a biologist believes that a taxonomic group is wrongly placed in the system...
| What are they allowed to do? Suggest
that it be moved to another group level.
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What are they generally not
allowed to do?
Arbitrarily just change the name of the group.. |
8. What are two features of deep-sea hydrothermal vents that make them good candidates
for the "starting place" of life?
...they were a source of hot chemical energy; they were a source
for the molecules needed for the process; they are a stable,
long-existing system
9. Briefly explain why similarities in embryos may persist long after related adult forms
become very very different.
...changes so early are much more likely to produce dramatic changes in
adults that would reduce their chances to be able to reproduce (and
maybe survive)
10. Put in proper order from largest to smallest: Class, Family, Genus, Kingdom, Order,
Phylum, Species, Subfamily, Superorder.
| 1 Kingdom |
2 Phylum |
3 Class |
| 4 Superorder |
5 Order |
6 Family |
| 7 Subfamily |
8 Genus |
9 Species |
11. What two ecosystems would have "prepped" organisms that lived there for a movement
up onto land?
...Tidal pools or shallow fresh water systems...
12. What are two different types of molecules used by scientists in comparative
biochemistry?
...could be metabolic molecules or long sequential molecules (proteins,
DNA, and RNA are all the same type of molecules here)
13. Define: pioneer organism.
...a species that moves in to a newly-available ecosystem (and usually
makes it usable to other species over time)...
14. What is the function of a homeogene?
...they are responsible for basic layout in early development of
embryos...
15. Why have ferns developed alternations of generations?
...they needed their sexual phase (but it requires water for sperm to
swim through), but developed an asexual phase with airborne spores to
spread themselves around...
16. The development of which feature was most important to plants being able to adapt to
life on land (there's more than 1 possible answer - just give one), and why?
...could be a support system, or a relationship with fungi to supply
nutrients, or ability to resist drying...it's tough to put other aspects
as high on the importance scale...
LONG ANSWER.
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 major challenges faced by organisms moving out of the water up onto the
land? There are more than four...
Resistance to drying.
Ability to support without water buoyancy. |
Dealing with fluctuating temperatures.
Dealing with strong direct sunlight. |
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Dealing with high oxygen levels. |
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Reproducing without water for sperm to swim through. |
2. For four of the Five Kingdoms of Living Things, give the proper name of that Kingdom
and those traits that set that Kingdom's members clearly apart from the other four.
a. MONERA
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All you need here is that cells have
no nuclei. |
b. PROTISTA
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Cells have nuclei, but that's not
enough (also true for c,d,e); also needs: group is mostly
single-celled forms |
c. FUNGI
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Multicelled (a & b have similar
single-celled forms); Heterotrophic, non-moving, absorb
nutrients through outside surfaces |
d. PLANTAE
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Photosynthetic (not enough - also true
in a & b) and multi-celled |
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e. ANIMALIA |
Multicelled, heterotrophic; consume
and digest food internally; usually can move |
3. Give three sets of differences that set male sex cells apart from female sex cells.
| SPERM |
EGG CELLS |
|
Much smaller |
Much larger |
|
Produced in much greater numbers |
Produced in much smaller numbers |
|
Must somehow get to egg cell |
Must wait for sperm to find it |
4. For the currently-accepted hypothesis for the Origins of Life on Earth, put the following
in order (number them) from earliest to latest.
| 4 |
Aerobic
respiration. |
6 |
Multicellular
forms. |
1 |
Chemical
evolution. |
3 |
Autotrophs. |
| 5 |
Eukaryotic
cells. |
8 |
Life on
Land. |
7 |
Cambrian
Explosion. |
2 |
Protocells. |
After the Earth and Primordial Soup formed, chemical evolution is
leading to first "living" molecules, before cells, and leads
to protocells, which aren't even prokaryotes yet. Once prokaryote
cells had evolved, autotrophs (when the soup ran out) and aerobic respiration
(after autotrophs had released lots of oxygen) evolved before the
evolution of eukaryote cells, which were necessary before you could have
multicelled forms. The Cambrian Explosion happened while Life was
still stuck in the oceans, and much later did Life move out onto land.
5. Name four different processes that could produce a catastrophe big enough to bring
about mass extinctions. There are more than 4...
Asteroid or Comet Impacts
Huge Volcanic Eruptions |
Ice Ages |
Continental drift connecting land masses
Continental drift producing major climate changes |
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6. Name the major steps in the life cycle of a pine tree. There is no "set" number of steps,
since they can be combined and/or split by different people.
| Seed sprouts into sprorophyte.
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| Plant grows and matures.
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Male cones produce and release
wind-spread pollen,
Which land on female cones.
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| Pollen produces pollen tube, down
which sperm travels to fertilize egg cell.
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| Fertilized egg used in production
of seed.
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| Cone opens and seeds are released
to be spread by wind.
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7. Give four sets of distinct differences between:
| MONOCOTS |
DICOTS |
| Leaf veins are
parallel.
|
Leaf veins branch. |
| Root system usually
fibrous (highly branched)
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Usually with taproot (One major root
with much smaller secondary roots) |
| Almost never woody
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Has many woody species |
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Flower parts in multiples of 3
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Flower parts in multiples of 4 or 5 |
| Single-part seeds
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2-part seeds |
Vascular bundle
patterns:
ring in roots, random in stems
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Vascular bundle patterns:
central "X" in roots, ring in stems |
NO KEY FOR BONUS QUESTIONS.
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.
Translate each word: Ontogeny recapitulates phylogeny. Three Points.
Water is considered to be absolutely essential to any "from scratch" evolution of living
things. What exactly makes it so important to the process? Four Points.
Where might one go to find ancient fossil stromatolites? Three Points.
What two systems might have combined to produce the first photosynthesis? Four Points.
What event in India was once linked to the extinction event that wiped out the dinosaurs?
Three Points.
Which modern group are thought to be direct descendants of the dinosaurs? Three Points.
What sort of clue is given by a flower's color? Three Points.
What plant structure is the silk on an ear of corn? Three Points.
A sprouting seed's root and stem uses which environmental cue to help them grow in the
right direction?
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