Ecology-Introduction
Ecology
Section I –Vocabulary
Below is a list of all of the biology vocabulary terms used in this Unit. By the end of the Unit, you will be able to write a working definition of each term and correctly use each term.
o / abiotic factor / o / density-dependent facor / o / mutualismo / ATP / o / density-independent factor / o / niche
o / biogeochemical cycle / o / ecological succession / o / nitrogen cycle
o / biotic factor / o / ecology / o / nitrogen fixation
o / birth rate / o / ecosystem / o / parasitism
o / Calvin Cycle / o / energy pyramid / o / photosynthesis
o / carbon cycle / o / exponential growth curve / o / pioneer species
o / carbon fixation / o / grana / o / population
o / carry capacity / o / growth curve / o / predator
o / chlorophyll / o / habitat / o / Prey
o / chloroplast / o / heat loss / o / species
o / commensalism / o / invasive species / o / stroma
o / competition / o / lichens / o / symbiosis
o / dark reaction / o / light reaction / o / thylakoid
o / death rate / o / limiting factor / o / thylakoid membrane
o / denitrification
Section 2 – Mastery Objectives / Critical Thinking Skills
1. Define ecology
2. Distinguish between abiotic and biotic factors
3. Use graphs to analyze the rate of growth and decline of populations
4. Calculate carrying capacity of an ecosystem
5. Distinguish between density dependent and density independent growth factors
6. Explain the links between predator-prey population growth
7. Show graphically how birth death and migration rates affect population size and growth over time
8. Trace the flow of four key chemical elements (carbon, hydrogen, oxygen and nitrogen) through their cycle
9. Predict the impact that a disruption in the cycle would have on an ecosystem
10. Identify the factors that control the order of appearance and disappearance of organisms in an ecosystem
11. Identify the different types of symbiotic relationships
12. Identify the criteria used to determine whether a species is invasive
13. Give at least three examples of local invasive species and their impact on the local ecosystem
Section 3A –Required Readings
· Miller and Levine – pp 67-73; 74-78; 90; 92-95; 119-122; 124-127
Section 3B –Relevant Websites
Refer to the class wiki (http://nnhsbiology.pbworks.com)
Section 4 –– Outside Class Assignments
Thoughtfully answer each of the following questions or comments. Include all your reasoning and show all your work wherever it is appropriate. To receive any credit for a question, your answer must be a correctly numbered restatement of the question or statement followed by a series of complete sentences. No phrases, partial answers or isolated numbers will be given credit! Your answer must stand alone without the reader knowing the question asked or statement made.
1. The number of individuals in a population varies with time. One important factor is food supply. Fox eat mice. The following table shows the populations of fox and mice in a small ecosystem studied over nine years.
Year / Number of Mice / Number of Foxes1983 / 1050 / 200
1984 / 800 / 425
1985 / 426 / 581
1986 / 730 / 300
1987 / 980 / 153
1988 / 620 / 399
1989 / 380 / 548
1990 / 680 / 403
1991 / 1010 / 255
a. Plot the number of mice by year. Remember time goes on the x axis.
b. Plot the number of fox by year on the same graph using a different color or symbol
c. Label the fox curve, the predator curve and the mice curve the prey curve.
d. What pattern do you see between the fox and mouse populations?
e. In 1989 the mouse population was at its lowest? How was the fox population affected (smaller, larger, the same)?
f. In 1985 the fox population was at its highest. How was the mouse population affected (smaller, larger, the same) ?
g. How long is the delay between a change in the mouse population and a change in the fox population? What would explain the delay?
2. You are to consider a community consisting of corn plants, carrot plants, rabbits who eat the corn, but prefer the carrots, field mice who eat the carrots, but prefer the corn leaves, sparrows who eat the corn kernels, foxes who eat the mice, but prefer the rabbits, hawks who eat the sparrows and mice, but prefer the rabbits, bushes in which the rabbits and mice hide, bacteria in the ground which eat dead plants and animals. Working with a partner, discuss the following questions and give your answers and the reasons for your answers. Be as brief as possible.
a) Draw a food web for this community. Identify the producers, herbivores, carnivores, an decomposers.
b) What would be the effect of an increase in the population of rabbits on the population of foxes?
c) What would be the effect of an increase in the population of foxes on the population of carrots?
d) What would be the effect of an increase in the population of foxes on the population of corn?
e) What would be the effect of an increase in the number of bushes on the number of hawks?
f) What would be the effect of an increase in the population of bushes on the population of corn?
g) If air pollution significantly decreased the amount of sunlight in the community, what might be the effect on the rabbit population?
h) What would you expect to be the limiting factor on the population of carrot plants? Why?
i) What would you expect to be the limiting factor on the population of hawks? Why?
j) Would you expect the community to contain more sparrows or more hawks? Why?
3) A 100 square mile plot of tropical rain forest was logged and burned as part of a massive farming effort to feed starving people.
a) What will happen to the levels of carbon dioxide and oxygen in the area just after the forest is destroyed? Once the crops are growing?
b) Will carbon dioxide and oxygen levels return to their previous levels? Why or why not?
4) Compare and contrast the roles of bacteria in the carbon and nitrogen cycles.
5) A massive meteor crashes into the earth. So much dust and ash are released into the atmosphere that sunlight is blocked for the entire summer.
i) What will happen to the local food web? Answer using the terms producers, consumers, trophic level and decomposers.
ii) One popular theory is that dinosaurs became extinct shortly after a meteor crashed into the earth in the Yucatan spewing up clouds of dust and smoke that blocked the sun for years. Given that Tyrannosaurus rex was a carnivore who ate Triceratops, an herbivore, how would their food web have been altered by the meteor crash?
iii) Explain what probably happened to the levels of oxygen and carbon dioxide in the air during and after the impact.
iv) How would the carbon and nitrogen cycles have been affected by this catastrophe?
6) Mount Monadnock in New Hampshire is the second most climbed summit in the world. By the beginning of the 1700’s, its summit was mostly cleared of trees. Only a small spruce forest remained. Around 1800, a fire burned over the mountain destroying most of the organic soil on the top of the mountain and removing the last habitat for wolves. After the fire, erosion began to expose the bedrock in the summit area.
a) Sketch the summit as it appears today and list the types of biotic factors you would expect to see on the summit if you went hiking there next weekend.
b) What species of plants and animals were the first to appear on the mountain after the fire?
c) In 100 years, what biotic factors would you expect your great grand children to see on the summit?
d) Will the spruce forest make a comeback on Mount Monadnock? Why or why not?
e) If yes, when and how will this happen?
7) Photosynthesis is the process by which light energy is captured and transduced into chemical energy that organisms can use to power their life processes.
a) Write the balanced chemical equation for photosynthesis.
b) Write the chemical equation for the light cycle and then explain what happens during this part of photosynthesis.
c) Write the chemical equation for the dark cycle and then explain what happens during this part of photosynthesis.
d) How are the light and the dark cycles in photosynthesis the same and different? (A Venn diagram would work well here.)