Download Pre-AP Biology Ecology Exam Study Guide

Pre-AP Biology
Ecology Exam Study Guide
Which type of evidence would indicate that one
species is better at competition against another
species for space or some other limiting resource?
If the population of one species decreases dramatically in the presence of
the second (see left) or if like in the barnacle example (right) the smaller
Chthamalus is restricted to just the high tide line by Balanus. When Balanus
was removed, Chthamalus covers to low-tide line.
Given a food-web, how would you correctly identify a:
producer, herbivore, carnivore, and omnivore?
Given a food-web, how would you correctly identify a:
producer, herbivore, carnivore, and omnivore?
H is a carnivore
C & D are herbivores
E is an
omnivore
A & B are producers such as plants
Describe and explain the logistic model of population
growth:
Describe and explain the logistic model of population
growth:
Red = growth starts slow (lag
phase) and then accelerates
(exponential)
Blue = growth slows as
density-dependent factors
such as competition for
resources limits growth
Dashed line = carrying
capacity
Describe the changes that occur in an ecosystem
during secondary ecological succession in Northern
Arizona, following a fire:
Describe the changes that occur in an ecosystem
during secondary ecological succession in Northern
Arizona, following a fire:
After fire kills the adult trees, aspen seedlings colonize. The aspen
grow to mature trees. Conifer seedlings sprout in the understory.
They are shade-adapted and readily grow up until they are as tall as
the aspen. The aspen die of old age, but no new aspen seedlings
sprout because they are not shade-tolerant and can not survive in the
understory of the conifer trees.
What kind of evidence would indicate that an
ecological relationship is mutualistic?
A mutualistic relationship benefits both organisms:
+ , +. For example, most (if not all plants) have a
mutualistic relationship with fungi called
mycorrhizae . The plant provides the fungus with
carbohydrates (energy in the form of sugars that
the plants produce via photosynthesis) and the
fungus coats the plant’s roots increasing the
surface area for the absorption of micronutrients
(such as minerals) and water.
How do keystone species such as the sea otter
affect the biodiversity of their habitats?
How do keystone species such as the sea otter
affect the biodiversity of their habitats?
Sea otters prey upon
urchins. Urchins feed on
kelp. If otter population
drops, sea urchin population
would increase and kelp
would decrease. As a result
of the loss of kelp in the
kelp-forest habitat, the
biodiversity of that habitat
would be expected to
decrease.
Draw a graph that shows the relationship between
predator and prey populations over time (like we
saw for the rabbit and lynx simulation). Add the
following to the graph: population of the
herbivore’s preferred plant food and population of
a plant that is not edible due to the presence of
poisonous chemical compounds.
Draw a graph that shows the relationship between
predator and prey populations over time (like we
saw for the rabbit and lynx simulation). Add the
following to the graph: population of the
herbivore’s preferred plant food and population of
a plant that is not edible due to the presence of
poisonous chemical compounds.
Inedible
plant
(ml)
1. What is the mean growth rate of P. caudatum
from day 2 to 6?
2. What does the carrying capacity of P. caudatum
appear to be?
(ml)
1. What is the mean growth rate of P. caudatum
from day 2 to 6? Approx. 50/4 = 12.5 ml/day
2. What does the carrying capacity of P. caudatum
appear to be? Approximately 70 ml
1. What effect does growing in a culture mixed with P.
aurelia have on the population growth rate of P.
caudatum?
2. What could be an explanation for this?
1. What effect does growing in a culture mixed with P.
aurelia have on the population growth rate of P.
caudatum? Eliminates it
2. What could be an explanation for this? competition
1.
2.
3.
4.
Name the primary producer
Name a primary consumer
Name a secondary consumer
What affect would a
reduction in light have on
this food web?
5. Explain your answer to #4
6. Which species would be
most negatively impacted by
a reduction of phytoplankton
and why?
1. Name the primary producer
phytoplankton
2. Name a primary consumer zooplankton
3. Name a secondary consumer squid
4. What affect would a reduction in light
have on this food web? Decrease
abundance at all levels
5. Explain your answer to #4 light is energy
entering food web, necessary for
photosynthesis
6. Which species would be most negatively
impacted by a reduction of phytoplankton
and why? Killer whale, takes a lot of
energy (prey that depend on
phytoplankton) to support top-predator
3.
a. Calculate the mean rate of
growth from day 5 to 10.
Record your answer to the
nearest whole #.
b. What is the carrying
capacity?
c. How would this species growth curve be affected if it
was grown with a second species with which it was in
competition with?
d. “” with which it was not in competition with?
3.
a. Calculate the mean rate of
growth from day 5 to 10.
Record your answer to the
nearest whole #. Slope,
rise/run = approx. 90 ml/day
b. What is the carrying
capacity? Approx. 900
c. How would this species growth curve be affected if it
was grown with a second species with which it was in
competition with? Carrying capacity would be lower
d. “” with which it was not in competition with?
unchanged
1. What effect would a reduction in the amount of
plants in this ecosystem have on the food web?
2. Explain your answer to #1:
1. What effect would a reduction in the amount of plants in this
ecosystem have on the food web? Reduction in abundance of
consumers, possible loss of top-predators
2. Explain your answer to #1: Energy flows through the food web
from plants through eating relationships, energy-loss at each
level, top-predators require the most energy to support
What is the pattern in expected
biodiversity for the islands shown
to the left?
Larger islands are expected to support more
species (higher biodiversity because of more
microclimates and niches).
Islands closer to the mainland are expected to
have higher biodiversity because they are more
likely to be colonized.
Island A is both largest and closest to mainland
– highest biodiversity; while C, which is both
smallest and farthest is expected to have the
lowest biodiversity.
The diagram above shows the pattern of habitat loss
and fragmentation over time. Predict and explain the
effect of this pattern on the biodiversity of the
habitat shown.
The diagram above shows the
pattern of habitat loss and
fragmentation over time. Predict
and explain the effect of this
pattern on the biodiversity of the
habitat shown.
As habitat is lost and becomes more fragmented, less
individuals are expected to be supported (especially those that
require large territories), as a result species will become extinct
and there will be a corresponding loss of biodiversity.
What are some density-dependent factors that can cause a
population’s growth to slow and level out at carrying
capacity?
What are some density-dependent factors that can cause a
population’s growth to slow and level out at carrying
capacity?
Competition for limited resources (i.e. food)
Territoriality
Predator-prey interactions
Disease
Toxic-waste buildup
Intrinsic factors
How can alien (nonnative) invasive species be so
successfully colonizing and spreading into native habitats?
Why are Alien Invasive Species so Successful?
They may have lost a population controlling
factor: left their predators, pathogens, or
parasites behind – no top-down control on
their population
They may have a novel evolutionary
advantage (chemical defense, enzyme,
competitive edge, etc.)
What percentage of the energy in plants makes it into the
bodies of (show set-up and circle the final answer):
a. Primary consumers
b. Secondary consumers
c. Tertiary consumers
Pyramid of Net Production
a. What % of energy in plants makes it to primary
consumers? 1,000/10,000 = 1/10 = 10 %
b. What % of energy in plants makes it to secondary
consumers? 100/10,000 = 1/100 = 1 %
c. What % of energy in plants makes it to tertiary
consumers? 10/10,000 = 1/1000 = 0.1%
Describe the energy-flow through the model
system below, by labeling the arrows:
Plant
Caterpillar
Respiration (Heat)
Light
Plant
Detritus
Respiration (Heat)
Biomass
consumed Caterpillar
Biomass
consumed
Feces (& detritus)
1. Energy enters Earth’s ecosystems as ________ and
exits as ________.
2. Energy _______ through Earth’s ecosystems.
3. Matter ______ through Earth’s ecosystems aided
by the action of organisms called ____________.
1. Energy enters Earth’s ecosystems as _light_ and exits
as _heat__.
2. Energy _flows_ through Earth’s ecosystems.
3. Matter _cycles_ through Earth’s ecosystems aided by
the action of organisms called ___detritivores____.
Population size
hare
lynx
Calculate the lag-time in, round to the nearest
month:
Population size
hare
lynx
Calculate the lag-time in, round to the nearest
month:
250 – 220 = approximately 30 months
1. What is the best explanation for the change in elk population?
2. How can the change in cottonwood abundance be explained?
3. If the wolf were to be removed from the Yellowstone ecosystem, how would you expect the elk
population would respond?
Elk population decreased after the wolf reintroduction because wolves are their predators. As a result of a
decrease in elk population (herbivore), the population of cottonwoods and willow increase. If the wolves
were once again removed, elk population would likely increase and cottonwood and willow likely decrease.
What is the likely reason for the difference in aspen hikes in the upland and riparian habitats?
When aspen are browsed (nibbled by herbivores) their growth is stunted, and thus their overall height is
reduced. This data shows that aspen in riparian areas (along streams) are larger than those in the uplands,
suggesting that there is less browsing along streams. The reason for this could be that the streambanks can
be steep and the stream can also be a barrier, both making herbivores more likely to be caught by wolves.
Thus prey avoid stream areas.