Ecology Review II Course: Biology 211
Supplemental Instruction Roe
Iowa State University
Date: Monday, April 27, 2009
____ Negative intraspecific interactions A. Random distribution
____ Positive intraspecific interactions B. Uniform distribution
____ No strong intraspecific interactions C. Clumped distribution
2. Compare the terms paired together in each row:
Biotic factors Abiotic factors
Prezygotic Barriers Postzygotic Barriers
Allopatric speciation Sympatric speciation
Logistic Growth Model Exponential growth model
Small-population approach Declining-population approach
Density-dependent factors Density-independent factors
Food chain Food web
Intraspecific Interactions Interspecific interactions
Ecosystem characteristics with high NPP Ecosystem characteristics with low NPP
3. Define the following terms: organism, population, community, and ecosystem.
4. Mark and recapture problem: Suppose that you capture 10 individuals of a rare
subspecies of brook trout from an impounded watershed. You place a pit tag (a very
small radio activated tag) in the body cavity of each individual and then release these
fish. You come back a month later and capture 20 fish and find that four of these are
individuals that you had previously captured and released. What is your best estimate of
the population size, N?
5. Density problem: What is the density of a population if there are 100 individuals in an
area that is 100 m2?
6. Rate of increase problem: What would the change in population be given the following
scenario? Is the population growing or declining? .. 600 squirrels are born in a
population and 400 squirrels in the same population die. Additionally, 100 squirrels
immigrate into the area and 150 squirrels emigrate from the population.
7. Survivorship Curves- Describe each type:
8. What is the competitive exclusion principle?
9. Logistic growth model math problem: Look on the board.
10. What are the effects of increasing CO2 levels?
11. What is a keystone species?
12. Describe the extinction vortex and how it can lead to the extinction of a small species.
13. Why is there so much plant biomass if there are herbivores?
14. Description of water cycle:
15. Description of carbon cycle:
16. Which of the following are important biotic factors that affect the structure and organization
of biotic communities?
A) precipitation, wind
B) Nutrient availablity, soil pH
C) predation, competition
D) temperature, water
E) Light intensity, seasonality
17. The main reason polar regions are cooler than the equator is because
A) There is more ice at the poles
B) Sunlight strikes the poles at a lower angle
C) The poles are farther from the sun
D) The atmosphere is thicker at the poles
E) The poles are permanently tilted away from the sun
18. Uniform spacing patterns observed in plants like the creosote bush are most often associated
B) Patterns of humidity
C) Random distribution of seeds
D) Competitive interactions among individuals
E) The concentration of nutrients
19. Which of the following describes having more than one reproductive episode during a
20. According to the competitive exclusion principle, two species cannot continue to occupy the