Download Unit 8: Community Interactions REVIEW GUIDE KEY Documentaries

Unit 8: Community Interactions REVIEW GUIDE KEY
Documentaries covered
 Trials of Life- Hunting & Escaping (2 questions)
 Trials of Life- Living Together (4 questions)
 Invasion of the Giant Pythons (3 questions)
Labs covered
 Owl Pellet Dissection (1 question; KNOW WHAT AN OWL PELLET IS)
 The Lesson of Kaibab (2 questions)
Topic #1 Biogeochemical Cycles (Lecture #5)
1. Define Biogeochemical cycle.
The paths of water, carbon, nitrogen, and phosphorus pass from the non-living environment
to living organisms and back to the non-living environment in closed circles.
2. What is the difference between the way ENERGY and MATTER move through
natural ecosystems?
Matter is recycled, energy is not (it flows in one direction)
3. Which biogeochemical cycle does NOT have an atmospheric phase?
Phosphorous cycle
4. Evaporation and Precipitation are associated with which of the biogeochemical
cycles?
The Water Cycle
5. Where is most of the water on earth found?
Ocean ecosystems
6. Where is phosphorous naturally found in the physical environment?
Phosphorous is naturally found in rocks and in soil minerals.
7. A farmer who grows and plows under some type of legume would enrich their soil
with which of the following nutrients: carbon, nitrogen, phosphorous (circle it)
8. Who carries out ‘nitrogen fixation’, the process whereby atmospheric nitrogen is
transformed to a usable form?
bacteria
9. What causes the ‘Dead Zone’ in the Gulf of Mexico?
Run-off of agricultural chemicals
10. Which biogeochemical cycle is greatly impacted by mining?
Phosphorous
11. How are humans impacting the carbon cycle?
Burning of fossil fuels, destroying vegetation that absorbs carbon dioxide, using appliances
powered by electricity.
Topic #2 Feeding Relationships (Unit 8; Lecture #1)
12. What is coevolution?
The process by which species evolve in response to other living members of their
ecosystem.
13. Give an example of coevolution.
Plants and their pollinators
14. Plant-Herbivore Balance- How does the population of herbivores influence the
population of plants? How does the population of plants influence the population of
herbivores?
When the population of plants decrease, the population of herbivores decrease. This allow
for the plant to reestablish itself (increase in population) and will be followed by an
increase in herbivores. If herbivores are not controlled by a predator or parasite, they
may overgraze the land, which can lead to the collapse of the ecosystem.
Herbivores coevolve with the plants that they eat.
15. What prevents herbivores from overgrazing the land?
Natural enemies keep the herbivore population below the overgrazing levels
16. Predator-Prey Balance- How does the population of predator influence the
population of prey? How does the population of prey influence the population of
predator?
When the population of prey organisms decrease, the population of predators decrease.
This causes an increase in prey, which is followed by an increase in predators. This causes
a decrease in the population of prey. REPEAT.
Predators coevolve with their hosts.
17. Define predator.
Any animal that lives by preying on other animals (usually) from a lower trophic level.
Example: A wolf that hunts, kills and then feeds on a moose.
18. Define prey.
Any animal species that is fed upon by another
19. Parasite-Host Balance- How does the population of parasite influence the
population of its host? How does the population of host species influence the
population of its parasite?
When the population of host organisms decrease, the population of parasites
decrease. This causes an increase in host, which is followed by an increase in
parasites. This causes a decrease of host. REPEAT.
Parasites coevolve with their hosts.
20. Define parasite.
An organism that lives in association with another organism (host), from which it
obtains organic nutrition
21. Define host.
The organism on/ in which a parasite lives. It is the “prey” of a parasite
22. Parasites are usually smaller/ bigger than their hosts. (circle correct word)
23. How is a parasite different from a predator?
Parasites rarely kill their hosts; unlike a predator, who kills their prey in order to feed.
24. What is meant by the term ‘carrying capacity’?
Carrying capacity is the maximum number of organisms that the ecosystem can
support on a sustained basis.
25. After a population surpasses its carrying capacity, competition for mates, food, &
shelter increases/ decreases (circle correct response).
26. What affect did the removal of predators have on the Kaibab deer?
Caused the deer population to grow rapidly beyond their carrying capacity, which let to
damage to the ecosystem due to overgrazing.
27. What happened to the carrying capacity of Kaibab Deer during the 1900’s? Explain.
It dropped, as a result of overgrazing.
28. Define population density.
The number of individuals per unit area
29. Define limiting factor.
Something that controls the growth or size of a population
30. Define density independent limiting factors and give two examples.
Environmental factors that affect population size regardless of the population’s
density
Examples: Winter storms, drought, tornado, forest fire
31. Define density dependent limiting factors and give two examples.
Limiting factors that affect large, dense populations more strongly than small, less
crowded ones. Examples: Disease carrying insects, predators, communicable disease
Topic #3 Symbiosis (Unit 8; Lecture #2)
32. Identify and define the type of symbiosis represented by the following scenario:
Bees and the flowers that they pollinate
__Mutualism_ : (Definition) _ a symbiotic association in which both partners benefit
33. Identify and define the type of symbiosis represented by the following scenario:
Tapeworm living in the gut of a human (see notes #2)
__Parasitism_________ : (Definition) __ a symbiotic association in which one partner
benefits and one partner is harmed.
34. Identify and define the type of symbiosis represented by the following scenario:
Orchids and Trees (see notes#2)
_Commensalism__ : (Definition) _ a symbiotic association in one partner benefits and one
is unaffected.
Topic #4 Competition & Niche Utilization (Unit 8; Lecture #3)
35. What is competition?
An ecological interaction that occurs when members of the same species require the same
resources (ex: food and space)
36. Different species share the same habitat, but can REDUCE competition among them
by occupying different _NICHES___.
37. What is meant by the term ‘niche’? What sort of factors does it include?
The functional role of an organism in its ecosystem. It includes factors such as where it
eats, what it eats, when it eats, how it attracts a mate, when it mates
38. What is the relationship between niche and habitat?
An organisms niche includes its habitat
39. What is a realized niche?
The niche that a species ultimately occupies
40. What is a fundamental niche?
The entire range of conditions an organism is potentially able to occupy within an
ecosystem.
41. What happens if the niches of two species overlap?
The organisms may have to complete directly.
42. No two species can occupy the same niche, at the same time. What is the name of
this ‘rule’?
Competitive Exclusion Principle
43. Sketch of graph of exponential growth. What would cause a population to grow in
such a way?
Invasive species tend to grow in this way! A population may grow in this way
if the species had no natural predators, was introduced to a new area and occupied an open
niche, or if the species has ‘weedy’ characteristics.
44. What affect do invasive species have on the ecosystems in which they ‘invade’?
They harm them, as they often outcompete native species for resources