EEES 1160 (Plants & Society)
Exam 2, version 1, Fall 2006
Name:
Instructions: Fill in answers on the accompanying "bubble" sheet. Remember, there is
only one correct answer per question. Write and "bubble in" name on bubble sheet. Turn
the bubble sheet in to me. * = extra-credit question.
1) Which equation below represents a summary of the complex metabolism of photosynthesis?
a- sugar (carbohydrate) + O2 (oxygen) → energy (ATP,NADH) + H2O (water)
b- CO2 (inorganic carbon dioxide) + H2O → sugar (organic carbon, carbohydrate) + O2
c- both can happen
d- none of the above
2) Photosynthesis is comprised of two sets of reactions: the “light” reactions that take place on
the thylakoid membranes of the chloroplast, and the “dark” (or Calvin cycle) reactions that take
place in the soluble stroma of the chloroplast. What is the purpose of the light reactions?
a- convert light to chemical energy
b- convert light to sugar
c- protect plant from “sunburn”
d- do photorespiration
3) What do the photosynthetic dark reactions do?
a- convert CO2 to water
b- make chemical energy in the form of ATP
c- use the energy from the light reactions to convert CO2 to sugar
d- provide the plant energy during the night
e- all of the above
4) Rubisco, the most abundant enzyme on Earth, is the enzyme that catalyzes the first step of the
dark reactions. Unfortunately, rubsico is also very slow and sloppy, as enzymes go. It
sometimes reacts with the wrong substrate, O2, instead of the correct one, CO2. Which of the
following is not correct of the wrong reaction?
a- wrong reaction, plus subsequent corrective metabolism, is called photorespiration
b- wastes energy and organic carbon
c- increases with temperature
d- occurs in all plants (C3, C4, CAM) equally
e- takes place only in the light, consumes O2, and releases CO2
5) Increases in which “greenhouse” gas in Earth’s atmosphere is thought to be the primary cause
of current global warming?
a- O2 (oxygen)
b- H2O (water)
c- CO2 (carbon dioxide)
d- ozone (O3)
e- uranium
6) The correct greenhouse gas above has increased in atmospheric concentration from
approximately (ca.) 280 to 370 parts per million (ppm) since the dawn of the pre-industrial age
(prior to ca. 1850) until 2007, and is expected to reach ca. 700 ppm by 2100. Plants having
which type pf photosynthetic metabolism will benefit most from this increase (all other things
remaining unchanged)?
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abcde-
C3
C4
CAM
all will benefit equally
none will benefit
7) What is the main difference between C3, C4, and CAM plants?
a- C3 plants have high levels of photorespiration
b- C4 & CAM plants have CO2-concentrating mechanisms which reduce photorespiration
c- C3 only does Calvin Cycle; C4/CAM do “special extra” reactions before the Calvin Cycle
d- none of the above are correct
e- a, b, & c are all correct
8) Which line in the graph below
represents the C3 (vs. C4) plant?
a- a
b- b
*9) Which line in the graph below
represents the C3 (vs. C4) plant?
a- a
b- b
10) Which line in the graph below represents humanproduced nitrogen (N) entering the global ecosystem N
cycle (i.e., converting N2 gas from the atmosphere to a
form that is usable by plants), and which represents
naturally produced N?
a- a = human N; b = natural N
b- a = natural N; b = human N
11) What is the underlying cause of the major current global environmental problems?
a- variation in solar warming of the Earth due to slight wobbles in Earth’s spin
b- human population growth
c- El Ninõ ocean cycles
d- recent increases in atmospheric CO2
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*12) Some responses to global warming can cause global warming to increase at an even faster
pace than otherwise (a feed-forward effect). Which of the following is an example of this?
a- increases in photosynthesis by plants
b- increases in carbon sequestration (immobilization) into the oceans
c- increases in soil warming, especially in the arctic
13) There are two kinds of cell division in eukaryotes: mitosis and meiosis (prokaryotes divide
by asexual fission). Which is the correct match below?
a- mitosis:sexual; meiosis:asexual
b- meiosis:sexual; mitosis:asexual
14) Why is a special kind of cell division required for sexual reproduction (i.e., making gametes,
like eggs and sperm)?
a- eggs & sperm are very complicated cells
b- gametes need to have half the number of chromosomes of the parents
c- gametes need to have twice the number of chromosomes of the parents
d- eggs & sperm do not contain chromosomes, unlike parent cells
15) The above-mentioned special type of cell division in making gametes also has an important
added benefit/function. What is this?
a- to ensure that the gametes are genetically identical to the parent
b- to ensure that the gametes are genetically different than the parent
16) Which of the following is the correct order of some major steps in plant evolution?
a- nervous system, amniotic egg, backbone, hair
b- vascular tissue, protected embryo, seeds with cones, seeds with flowers, stomates
c- protected embryo, stomates, vascular tissue, seeds with cones, seeds with flowers
d- stomates, protected embryo, vascular tissue, seeds with flowers, seeds with cones
17) During the course of plant evolution, the relative importance of the haploid (1N) phase has
been decreased, and the diploid (2N) phase has become the dominant phase. Why is this
advantageous?
a- the diploid phase has more genetic resources
b- the diploid phase has fewer chromosomes, which decreases mutation rates
c- the diploid phase has only mitosis, which is a quicker way to replicate a cell
18) Mosses (and their relatives) and ferns (and their relatives) reproduce by spores, not seeds.
Why are seeds an advantage over spores?
a- embro vs. single cell
b- multi- vs. single-cellular nutrition
c- multi- vs. single-cellular protective shell
d- diploid vs. haploid
e- all of the above
19) From what group of organisms did plants evolve?
a- fungi
b- cyanobacteria (also known as blue-green algae)
c- green algae
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20) Flowering plants are the pinnacle of plant evolution, dominating other kinds of plants
ecologically, economically, and in terms of number of species? Why have these plants been the
most successful type of plant?
a- efficiency of pollination (sperm transfer from dad to mom) improved by partnership with
animals
b- seed dispersal away from mom improved by partnership with animals
c- flowers are cheap to make
d- a & b
e- a, b, & c
21) Charles Darwin was not the first to suggest that life on earth has evolved over time. What is
Darwin mainly noted for?
a- He was the first to discover and correctly interpret fossils.
b- He proposed a unique mechanism to explain how evolution occurred.
c- He was the first to suggest that organisms over-reproduce.
22) Darwin’s “Theory of Natural Selection” includes the ideas that:
a- the fittest organisms tend to survive
b- traits that increase survival tend to be passed to offspring
c- a & b lead to an increase in frequency of adaptive traits in the next generation
d- a, b, & c
e- a & b only
23) From a biological perspective, what is the purpose of sex?
a- to increase the number of offspring
b- to feel good
c- to increase genetic variability of offspring
24) What determines an organism’s phenotype?
a- genotype (genetic sequence)
b- environment during lifetime
c- both a & b
d- neither a or b, as phenotype is a fancy word for your blood type
25) Which of the following cannot lead to changes in the frequency of a gene in a population?
a- mitosis
b- natural or artificial selection
c- migration
d- hybridization
e- polyploidy
26) Identify the correct match below.
a- micro-evolution: evolution within a species
b- macro-evolution: evolution of new species
c- evolution: change in the gene frequencies within a group of related organisms
d- all are correct
e- only “b” is correct
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*27) An Andropogon gerardii plant happens to pollinate an Andropogon virginicus plant. The
resultant offspring reproduces asexually (vegetative reproduction), and then sexual reproduction
among these vegetative clones begins, which produces viable offspring. Which of the following
correctly describes what has just taken place?
a- micro-evolution by sexual selection between related populations of a species
b- micro-evolution by natural selection within a species
c- macro-evolution by mutation between related genera in the same order
d- macro-evolution by hybridization between related species in the same genus
28) Why do leaves change color in the fall in temperate plants?
a- chlorophyll is degraded to recover nitrogen and magnesium, allowing carotenoids to be
visible, which are not degraded since they contain only carbon and hydrogen
b- chlorophyll is converted to carotenoids
29) What cues do temperate plants use to decide when to change colors and drop leaves in the
fall?
a- light
b- day length
c- stress
d- a, b, & c
e- b only
30) Which group evolved onto land first? Plants or animals?
a- plants
b- animals
*31) Is the following life cycle that of a plant or an animal?
a- plant
b- animal
32) What color of light is absorbed least by leaves, and hence is least efficient for
photosynthesis?
a- red
b- green
c- blue
33) Leaves of which kind of plant are generally higher in protein & minerals, and hence better
for humans as food?
a- C3
b- C4
34) Why, mostly, is atmospheric CO2 increasing?
a- burning of fossil fuels
b- currently unknown
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