Ecology Pyramids
1.
a. Sunlight
b. 3190000kcal per square meter per year
2.
3.
a. .8%
b. Photosynthesis
4. By eating the organisms in the previous level
5. 400o0 kcal
6.
7.
8. 90% of energy is lost as heat as it is transferred through trophic levels
9. .6%
10. .09%
11. Only a tiny fraction of the original energy remains. The biomass would have to increase
substantially if this system were to support another trophic level beyond the hawk
12. Since little energy is available for a single hawk, there would not be enough energy in an
ecosystem to support a large population of hawks
13. Any photosynthesizing organism such as other trees, flowers grasses and moss
14. Omnivores, carnivores, anything that eats herbivores
15. Both have the same organisms in the same trophic levels. Both have the same number of
trophic levels. Pyramid A has 2 Oak trees in the first trophic level while pyramid B has 100,
000 oak leaves in the first trophic level. The shape is different
16. In pyramid B, the number of organisms decreases from one level to the next. In pyramid A , the
first level has a small number of organisms and the remaining levels follow the same pattern as
in pyramid A
17. The oak tree is the same, but the caterpillars eat only the oak tree leaves
18. The producers in Pyramid A are two oak trees, but the actual trophic source on these two
producers is tens of thousands of leaves. Only the leaves are eaten by the caterpillars, so the
number of leaves is much more relevant than the number of trees
19. 11,000 g/m
20. 40g/m
21. The biomass decreases steadily
22. No. the mass of the producers is smaller than the mass of primary consumers. After that level,
the biomass of each trophic level decreases steadily
23. Photoplankton reproduce rapidly so they can sustain a large number of primary producers
24. Biomass varies drasticalley with different organisms, the important issue is not the number of
organisms, but now much of that mass is used as food. Another important issue is the speed
with which food sources grow and reproduce
Nutrient Cycles
Water Cycle
1. Water
2. Atmosphere, surface water, groundwater, and oceans
3. In the aquifer
4. Evaporation and transpiration
5. Surface runoff and groundwater flow
6. Precipitation
7. As water vapor condenses, pollutants could be brought down to contaminate rivers, streams, lakes
and oceans
8. Precipitation and runoff would be the most responsible processes. Precipitation carries air
pollutants into water, while runoff collects any pollutants that are in our ground into the water
supply. The action of percolation and transpiration can filter and clean the water. Evaporation and
transpiration produce water vapor, which is probably the cleanest water on earth at this point.
9. Absorption and transpiration by plants and percolation
10. If the water on Earth is polluted anywhere in the cycle, it affects the water system in general.
Percolation and plant use limited in what they can do to clean the water. If our atmosphere is
polluted, it will the pollute the water. If there is pollution ion the ground, runoff will take it to the
lakes, rivers and oceans. The water that is on Earth today is the same water that has been there
from the beginning and will continue to be the water that is available to us.
Carbon cycle
11. Carbon
12. Respiration from animals and plants, and combustion
13.
a. photosynthesis
b. plants and other photosynthetic organisms
14.
a. decomposing fungi, bacteria and worms
b. the carbon would not be recycled into the atmosphere; it would be locked in the waste and
dead matter, leaving less and less carbon dioxide for photosynthesis, Meanwhile, the
wastes and dead organisms would pile up
15.
a. coal, oil, peat and natural gas
b. fossil fuels
c. we burn them as energy sources
d. combustion
16. Using a gas stove, driving in a car, flying on an airplane, riding the bus to school, using an outdoor
grill, using any electrical appliance when the electricity is made from power plants that burn fossil
fuels
17. Nearly half of the electricity in the US is generated from the combustion of coal
18. Oil, natural gas, and coal. Some may include peat, although it takes much less time to form
19. WE are releasing the stored carbon into the atmosphere, thsu increasing the amount of CO2 in the
atmosphere. WE are releasing the carbon stores faster than they can be replenished by nature.
The balance that had been in place by storing some of the carbon in the carob sinks has been
thrown off by human used of fossil fuels.
20. We are increasing the amount of CO2 in the atmosphere by reduction the mass of photosynthetic
organisms with deforestation and ocean pollution. Increases in greenhouse gases have been linked
to global warming. This can melt ice caps, causes flooding and drastically affect weather patterns,
as well as change the temperature of environments and affect the survival of organisms.
Nitrogen Cycle
21. Nitrogen
22. Nitrogen- fixing bacteria, decomposing bacteria, nitrifying bacteria, and denitrifying bacteria
23. Nitrogen fixation by N-fixing bacteria in the soil and in the root nodules of legumes
24. By conversion to ammonia and ammonium compounds
25. Nitrates
26. They convert nitrates, which are what plants need, back to atmospheric nitrogen
27. The nitrogen cycle would be unbalanced. The nitrates would not be converted to nitrates and the
ammonia compound would accumulate.
Ecological relationships
1.
a. number of hares
b. number of lynx
c. 1000
2. 155,000
3. 5000
4. the number of lynx is usually also high
5. the population of lynx decline also
6. because a lot of food is available more lynx are likely to survive and their population can increase
7.
a. if a large food supply is available, then the predator population can increase
b. when the predator population becomes to large, they consume the food and so the overall
prey population is reduced
8. the amount of food available to the hares
Symbiosis
9.
a. only one- the flea
b. the dog is harmed
c. human and tapeworm
10.
a. both
b. no
c. termite and cellulose-digesting bacteria
11.
a. only one benefits, the remora
b. no
c. cattle and cattle egret
12. Table should read
a. Parasitism
b. Mutualism
c. Mutualism
d. Commensalism
e. Commensalism
f. Parasitism
13. Answers will vary
Inter and intra competition
14. P.aurelia and P. caudatum
15. B
16. C
17. In group A the two species are grown separately and in graph B they are grown together
18. After 20 days P. aurelia reaches a larger population
19. While some difference is seen, it is not significant
20.
a. the population of P. caudatum is dramatically affected whit it is grown with P. Aurelia,
whereas little effect is seen on the population size of P. aurelia when grown with P.
caudatum
b. the larger species requires more nutrients to survive, It is unable to compete with the
smaller species that has a lower nutrient requirement
21. interspecific competition is competition between two or more different species of organisms
22.
a. Tadpoles of R. tigrini
b. Food, space
23. Approximately 0.75 g
24. Between 2-3 weeks
25. Increases to 6 weeks
26. Increases even more to between 8-9 weeks
27. The tadpoles are all competing for limited amounts of food so they will not be able to grow as
quickly and reach the minimum size required for metamorphosis
28. Intraspecific competition only involves on species
Succession
1.
2.
3.
4.
5.
6.
7.
8.
9.
a. Barren
b. No
c. There is no soil, only rock, so roots would not be able to take hold and there is also a lack of
nutrients
a. Small ferns, mosses and lichens
b. Seed blown by the wind, dropped by birds, etc.
a. Diagram B
b. Low nutrient requirements, small or low growing shallow roots systems
Taller plants can receive more sunlight and shade out smaller plants therefore decreasing the
competition. More sunlight would increase the rate of photosynthesis helping the plant grow
The number of pioneer organisms because they are struggling to survive
As the plant dies out, they decay and enrich the composition of the soil, adding humus and
nutrients.
Grazing animals would leave footprints for the seeds to lie in and leave manure to fertilize the
seeds. They consume early pioneer species to make room for the next colonizers and aid in seed
dispersal
The level of grazing can impact any further succession as the animals eat the young plant shoots
Primary succession in the successive rise and fall of population of plants from original colonizers
to mature trees and shrubs, beginning with barren rock that has no initial soil layer
10.
11. The trees are taller so they can out-compete other plants for light, they are slower growing so they
can withstand short term changes in conditions
12. Temperature, amount of light and length of day and water availability.
13.
a. The climax community
b. A fire has burned the forest and destroyed it
c. Natural lightning or man started the fire
d. The process of succession will have to start over again
14. Yes evidence is provided in diagram F, where once again a climax community is established
15. There is no colonizing by lichens and mosses as soil or some other substrate is already present.
This speeds up the recovery time from hundreds of years to tens of years
16. Because the already present climax community was set back by the fire and is starting form an
area with soil rather than starting from a barren land
17.
a. Primary succession
b. Secondary succession
c. Secondary succession
d. Primary succession
18. Not always. Man is responsible for deforestation by cutting down trees for lumber or land
development
19. Forest managements, controlled burning, managed animal grazing
20. Selective logging will open up small spaces for light penetration, which allows existing saplings to
grow rapidly and fill in the gaps. Clear cutting of large areas will open up land and begin the
process of full decondary succession so the area will take longer to regenerate.