Download ES 100: Environmental Ecology

ES 100: Environmental Ecology
Midterm Exam
October 24th, 2005
Name:________________________________
TA:
________________________________
200 Points/ 6 Pages--Point values are shown in parentheses after the question number.
1. (24) Look at the biome map on the projection screen. Fill in the number that corresponds
to the correct location of the following biomes, and the plant/animal from the list below
that exhibits a particular adaptation to the biome.
Map Number
Biome
Plant/animal exhibiting
adaptive trait to biome
Desert
Tundra
Grassland
Chaparral
Tropical Forest
Boreal Forest
Plants/animals: cactus, prairie dog, pine tree, epiphyte, sedge (low-lying plant),
coast live oak
2. (18) Given:
 K  N1  a12 N 2 
dN1

 r1 N1  1
dt
K1


The above logistic growth equation accounts for: (answer “yes” or “no” in the blanks below)
_______Carrying capacity
_______ Predation or competition
_______ Commensalism
_______ Density dependent factors
_______ Density independent factors
_______ Age structure
3. (12) We all know that M.O.L.E. influences local climate. What does the acronym stand
for?
M:_______________________
O:_______________________
L:_______________________
E:________________________
(10)
Explain how one of the above four factors influences climate.
4. (16) Tomato crops are often selectively bred to maximize the size of their fruit. Predict
how the root size of a farmed tomato would compare to the roots of a wild tomato? How
might this impact soil and nutrient loss on agricultural land?
(Note: do NOT consider genetic modification, only selective breeding).
5. (12) What type of relationship do plants have with mychorrizal fungi? Explain.
6. (16) According to metapopulation theory, sub-populations of interacting species can be
classified as sources and sinks. Explain the difference between sources and sinks in
terms of reproductive fitness.
Source:
Are sources necessary for long-term viability of the total population? Why(not)?
Sink:
Are sinks necessary for long-term viability of the total population? Why(not)?
7. (8) List four major factors that influence soil nutrient availability:
1.______________________________________
2.______________________________________
3.______________________________________
4.______________________________________
8. (16) List 4 characteristics of opportunists, and 4 characteristics of competitors:
Opportunists
Competitors
____________________________
_____________________________
____________________________
_____________________________
____________________________
_____________________________
____________________________
_____________________________
9. (14 points)
Note: the dotted line represents the
theoretical growth curve, the solid line
represents the actual growth curve.
1. (8) List two plausible reasons for the declines in population size in the graph above.
2. (6) Do you believe that this organism is an r-strategist, or a k-strategist? Why?
10. (14 points)
Does the data presented above support the predictions of optimal foraging theory? Explain.
CROSSWORD (4 points per word, 40 points total)
Across:
1.
2.
3.
4.
This macronutrient does NOT have a gaseous state.
The name of my friend the great horned owl.
When a12<1, __________-specific competition regulates the population growth of species 1.
The total of all biotic and abiotic factors that determine how an organism fits into its
environment is called its _____________.
5. Desert plants evolved this type of photosynthesis to prevent water loss from their stomata.
Down:
6. A group of similarly aged organisms is called a _________.
7. Exponential population growth/decline results from a _________intrinsic growth rate.
8. Dark brown or black residue of organic matter found in the A horizon of soil.
9. These nitrogen-fixing bacteria form nodules on the roots of legumes.
10. Endothermic organisms spend much of their energy producing __________.
7
1
9
8
6
3
2
10
4
5