Name ______Date ______Section ______
Ecology Unit Study Guide
PART 1 – FOOD WEB: Study the food web below. Then answer the questions that follow.
1. Choose one food chain from the food web above that has at least four (4) trophic levels.
a. Copy it in the space below (you don’t have to include pictures).
b. Label the producer and each trophic level.
2. Identify at least one (1) decomposer in the food web. ______
3. Identify one organism that represents more than one trophic level. ______
4. Pretend that the rabbit population experienced a severe decrease.
a. Describe one possible cause for the decrease.
______
b. Describe one possible effect for the decrease.
______
5. This food web shows relationships between predators and prey. Fill out the chart below with three (3) examples of predators from the food web and give an example of a prey animal for each predator.
Predator / Prey6. This food web includes herbivores and carnivores. Fill out the chart below with three (3) examples of each from the food web above.
Herbivore / Carnivore7. BIO MCAS CHECK! Study the food web below. Then answer the questions that follow.
a.Identify the three (3) producers in this food web.
______
b. Identify five (5) consumers in this food web.
______
______
c.In this ecosystem, is more energy available to the field mouse population from eating spiders or from eating oats? Explain your answer.
______
PART 2 – SYMBIOSIS: Read each passage and answer the questions that follow. Remember, in some symbiotic relationships neither organism is harmed, so that part may be left blank for certain passages. You will use one type of symbiotic relationship more than once.
1. A good example of symbiosis is the clownfish and the sea anemone. The clownfish can come in contact with the stinging tentacles of the sea anemone and not be harmed by them. At the same time, it receives protection from its enemies. The clownfish feeds the anemone by gathering nutrients and also leaving nutritional waste on the tentacles.
a. Symbiotic relationship (circle one):
mutualism parasitism commensalism
b. Benefiting organism(s): ______
c. Benefits: ______
d. Harmed organism(s): ______
e. Harms: ______
2. There are several well-known associations between birds and large mammals. Cattle egrets (a small bird), for example, are often seen in the company of buffalo and elephants. They flourish on the insects kicked up by the feet of these animals. The egrets appear to be aware of approaching danger more quickly than their hosts are and it is likely that their actions in this respect serve to warn their larger companions.
a. Symbiotic relationship (circle one):
mutualism parasitism commensalism
b. Benefiting organism(s): ______
c. Benefits: ______
d. Harmed organism(s): ______
e. Harms: ______
3. Dodder (Cuscuta sp.) is a type of plant that is often found twined round the stems of clover plants or grasses. Each Dodder plant consists of a long slender yellow or pinkish stem, with the leaves reduced to tiny scales, and no roots for most of its life cycle. At intervals along the twining stem small root-like structures, called haustoria, link the Dodder to its host and penetrate to the host's vascular bundles. In this way, the Dodder obtains organic nutrients, water, and minerals salts directly from the host. The Dodder is not fussy about its host. Any herbaceous plant can be infected. If plants are densely packed, dodder will spread rapidly to adjacent plants.
a. Symbiotic relationship (circle one):
mutualism parasitism commensalism
b. Benefiting organism(s): ______
c. Benefits: ______
d. Harmed organism(s): ______
e. Harms: ______
4. Pseudoscorpions are small, predaceous arthropods less than 1 centimeter in length. These scorpion-like animals have pincers, but they do not sting like scorpions do. Pseudoscorpions are very common, but are usually overlooked because of their small size. As a result, they can hide very easily in many different places. Some pseudoscorpions conceal themselves under the wing covers of large beetles. The pseudoscorpions can be dispersed by “hitchhiking” on the beetles, thus allowing them to cover large areas in search of food, mates, etc. The beetles are not affected by the pseudoscorpions.
a. Symbiotic relationship (circle one):
mutualism parasitism commensalism
b. Benefiting organism(s): ______
c. Benefits: ______
d. Harmed organism(s): ______
e. Harms: ______
PART 3 – Abiotic Factors: Answer the questions below about abiotic factors.
1. What is the difference between an abiotic factor and a biotic factor?
______
2. Describe the importance of chemical recycling in the biosphere.
______
3. Below is a picture of the water cycle. Label: accumulation, condensation, evaporation, precipitation, run-off, and transpiration. NOTE: You may use some terms more than once.
4. Suppose there is an increase in water accumulation in a forest ecosystem. How might that affect the biotic factors of the ecosystem?
5. Below is a picture of the nitrogen cycle. Study the picture and answer the questions that follow.
a. What form does nitrogen need to be in for plants to use it? ______
b. Which forms of nitrogen can plants NOT use? ______
c. How would the plants be affected if the bacteria were removed from the nitrogen cycle?
______
6. A grassland ecosystem experiences a drought one summer.
a. What a change in which abiotic factor is primarily causing this situation? (Circle one).
sunlight water nitrogen oxygen temperature
b. What other abiotic factors from the list may also be involved?(Circle them).
sunlight water nitrogen oxygen temperature
c. Explain how this drought may disrupt the food web shown below.
______
1