Download (Ecology) Study Guide KEY

Ecology study guide – Pre-AP Biology KEY
List the 8 biomes starting at the equator and traveling toward the poles. Provide a brief description
of ecosystem of that area.
1. Tropical Forest (rain forest and dry)
 Temperature: warm to high
 Rainfall: varied – heavy
 Plants: thorny shrubs, deciduous trees, & succulents. (very diverse)
 Sunlight: little reaches the forest floor.
 Habitats: floor –> canopy.
o Poor soil, due to high temp & heavy rains (leaching).
 Animals: monkeys, birds, snakes, bats, frogs – tree dwelling.
 The Rain Forest contains about 45% of all animal species
o HIGH TEMP & HIGH WATER = LOTS OF PLANTS (PRODUCERS) SO
LOTS OF ENERGY AVAILABLE FOR ANIMALS (PYRMAMID OF
ENERGY, PYRAMID OF NUMBERS)
2. Savanna
 Temperature: warm year round
o Rainfall: moderate rainfall (with long periods of drought) BIOME DEFINED
MAINLY BY THIS
 Plants: grasses & scattered trees.
o growing point below ground & resistance to periods of drought.
 Habitats: migratory
 Poor soil, lack of moisture, grazing animals, & fires inhibit most trees.
o Biome is dependent upon fires to keep nutrient rich enough to support life
 Animals: large grazing mammals, insects, burrowing animals, predators (lions &
cheetahs).
3. Deserts
• Temperature: very hot, and cold (Antarctica)
• Rainfall: dry
• Plants: none, deep rooted shrubs, succulents.
– waxy coating to prevent water loss
– many seeds that remain dormant until it rains
• Sunlight: extreme
• Habitats: burrows, active at night
• Animals: ants, birds, rodents, lizards, snakes, & hawks.
4. Chaparral
• Temperature: mild winter, hot summer
• Rainfall: rain in winter, dry in summer
• Plants: dense shrubs with tough evergreen leaves. Seasonal plants.
– Food reserves in roots allow for rapid growth after frequent fires.
– Seeds only germinate after hot fire.
• Animals: deer, birds, rodents, lizards & snakes
5. Temperate grasslands (Prairies)
 Temperature: relatively cold
 Rainfall: rain, but periodic severe droughts
 Plants: grass, mostly treeless
o fire & grazing prevents tree growth
 Habitats: bird nests on ground, burrows.
 Animals: large grazing mammals (bison, wild horses).
 Soil supports diverse microorganisms & small animals.
 One of the most productive agricultural regions in the world
6. Temperate (deciduous) Forest
 Temperature: cold winter, hot summer
1.
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7.
8.
Rainfall: high precipitation
Plants: deciduous trees (oak, hickory, maple)
Habitats: rich soil, leaf litter, burrow
Animals: invertebrates, mice, shrew, squirrels, birds, bobcats, foxes, bears, & mountain
lions.
 Most destroyed by loggers & urban development.
Taiga (Coniferous) Forest• Temperature: long cold winters, short wet summers
• Rainfall: considerable precipitation (snow)
• Plants: cone bearing evergreens
– (spruce, pine, fur)
• Habitats: soil thin & acidic
• Animals: moose, elk, bears, wolves, hares, migratory birds.
• Heavily logged.
• Largest terrestrial biome
Tundra
• Temperature: extremely cold
• Rainfall: little
• Plants: no trees, shrubs, grasses, mosses, and lichens.
– Permafrost prevents deep root penetration
• Sunlight: little light for much of the winter, constant daylight in summer
• Habitats: migratory (summer is a breeding ground), high altitude, permafrost, soil
continually saturated due to poor drainage and slow evaporation.
• Animals: well insulated (oxen & caribou), lemmings, fox, snowy owl.
• During the summer, clouds of mosquitoes fill the air due to the marshy ground.
2.
Identify the following as biotic or abiotic factors affecting an ecosystem.
a. Rain - Abiotic
b. Wind - Abiotic
c. Predation - Biotic
d. soil nutrients - Abiotic
e. temperature - Abiotic
f. amount of sunlight - Abiotic
g. competition - Biotic
h. water availability - Abiotic
i. living organisms – Biotic
3.
What is the difference between primary succession and secondary succession?
Both involved the progression of an ever-changing community (Plants gradually get bigger
so gradually can support more animal life). The primary difference is that primary
succession begins from bare rock (no life before) and secondary succession begins after a
disaster that kills an already present community (fire, flood, etc.). Secondary occurs faster
because there is already nutrient-rich soil to support bigger life.
4.
What are the characteristics of a pioneer species?
Autotrophic
Smaller
Able to survive very harsh conditions (there has been no other life there before so no support
whatsoever).
5.
What type of interaction occurs between two different species that occupy the same niche?
COMPETITION
6. Complete the following table showing the positive and negative effects of interspecific
interactions. Also provide and example of each.
Interspecific interaction
Effect on species 1
Effect on species 2
Example
Competition
Scorpion vs. Spider
Mutualism
+
+
Endosymbiosis
Predation
+
Snake / Mouse
Herbivory
parasitism
+
+
-
Cow / Grass
Tick / Human
7.
Termites have a protozoan that lives in their intestines and helps breaks down the cellulose that
they consume. What type of interaction is this? Mutualism (just because it lives inside of it
doesn’t make it a parasite. They both benefit. Just like the beneficial bacteria that life in/on
you).
8.
What is a keystone species?
Species who has a very important niche in an ecosystem that impacts most others in the
community.
9.
What is the difference in a population and a community?
Population = ONE species in one area
Community = ALL the species in one area
10. What is the difference in a biome and an ecosystem?
Biome is bigger. It is a large geographical area that has the same typical ecosystem (same
sunlight, same precipitation, same plants, same animals)
11. Using the following diagram, list ALL of the following terms to each species. Some terms will be
used more than once and some species will have more than 1 description.
Primary Consumer,
Tertiary Consumer,
Omnivore, Carnivore, Decomposer
Secondary Consumer,
Producer, Herbivore,
A: Producer (it makes its own food/doesn’t eat anything else)
B: Primary Consumer, Herbivore (A primary consumer will always be an herbivore because
they are the first consumer [so they are eating the producer])
C: Primary Consumer in middle chain, Herbivore in middle chain, Secondary Consumer in
bottom chain, Carnivore in bottom chain (because it is eating the primary consumer),
Omnivore because eats plant and animal
D: Secondary Consumer in middle chain, Carnivore in bottom and middle chain, Tertiary
consumer in bottom chain (NOT AN OMNIVORE/HERBIVORE BECAUSE DOESN’T
EAT A)
E: Decomposer (everything, even the top of the food chain, is eventually broken down by
this)
12. Answer the following questions concerning the WATER CYCLE.
a. Why do we need water?
Homeostasis, hydrolysis, etc.
b. What is transpiration?
Plant losing water through stomata
c. What type of bond is broken when water experiences evaporation or transpiration?
Hydrogen bond between separate water molecules
13. Answer the following questions concerning the CARBON CYCLE.
a. Why do we need carbon?
Hydrocarbons (carbons with hydrogen bound to it) are the BACKBONE of ALL
organic molecules (lipids, proteins, nucleic acids, and carbhohydrates).
b. What two processes cycle carbon from an inorganic (CO 2) form to organic (C6H12O6)?
Photosynthesis converts CO2 to Glucose and Cellular Respiration converts Glucose
to CO2
c. How does burning fossil fuels lead to the Greenhouse Effect?
It ADDS more CO2 to the total amount in the cycle (because we are burning very
dense material [coal, oil, etc] that is full of carbon that would’ve not otherwise been
converted to CO2). There is so much CO2 that plants can’t pull it all from the air so
it forms a “blanket” around the Earth. This blanket traps heat in the Earth’s
atmosphere, increasing the annual AVERAGE temperature (in general,
temperature is increasing. There are outliers like this year where it is on average
colder).
14. Answer the following questions concerning the NITROGEN CYCLE.
a. Why do we need nitrogen?
DNA and proteins
b. When atmospheric nitrogen (N2) is converted to Ammonium (NH4+), this process is
called what? Nitrogen Fixation (beneficial bacteria are “fixing” nitrogen to a form
that plants can use it [assimilation])
c. When ammonium (NH4) is converted to nitrite (NO2), and the nitrite (NO2) is then again
converted into nitrate (NO3), this process is called what? Nitrification (the process of
creating nitrates)
d. What form does nitrogen need to be in for assimilation to occur? (Ammonion Ion
[NH4+] or nitrates (NO3-)
e. When there is an excess of nitrate, or a shortage of oxygen, nitrate (NO 3) can be broken
down to release the nitrogen back into the atmosphere in the form of a gas (N 2). What is
this process called? Denitrification (the process of getting rid of nitrates)
f. How do animals get their nitrogen?
Eating plants to get their AMINO ACIDS. (WE GET ALL OF OUR ORGANIC
MATERIAL[CARBON, PHOSPHOROUS, NITROGEN, ETC.] FROM EATING
PLANTS
g. What is eutrophication?
We OVERFERTALIZE plants which causes an excess of NITROGEN AND
PHOSPHOROUS in the soil. These elements get caught in GROUND WATER
where they are carried to LAKES AND PONDS. This basically means that we are
FERTILIZING THE WATER which allows ALGEA (A PHOTOSYNTHETIC
PROTIST) to rapidly grow. This creates an ALGAE BLANKET on the water that
prevents any sunlight from getting in. This causes the DEATH OF THE PLANTS
AND EVENTUALLY THE DEATH OF ALL ANIMALS in the body of water.
15. Answer the following questions concerning the PHOSPHOROUS CYCLE.
a. Why do we need phosphorous?
ATP, Phospholipids, DNA/RNA
b. What process removes phosphorous from rocks? Weathering
16. Answer the following questions about the PYRAMID OF ENERGY.
a. How much energy is passed on to each trophic level? 10% passed on (90% used
up/lost)
b. What happens to all of the energy that is not passed on?
Each trophic level USES the energy to make ATP to maintain homeostasis, move,
grow, etc. As ATP is used, energy is LOST AS HEAT.
17. Answer the following questions concerning the PYRAMID OF NUMBERS and the PYRAMID
OF BIOMASS.
a. What does each of these demonstrate (you need a separate answer for each pyramid)?
Pyramid of Numbers = the population of a community decreases by 90% each
trophic level because the energy decreases by 90% (so there isn’t enough energy to
support as many organisms)
Pyramid of Biomass = the amount of biomass (dry organic weight – mostly proteins)
decreases by 90% each trophic level for the same reason
b. Why do both of these mirror (look like) the Pyramid of Energy?
Reason explained above
18. Answer the following questions concerning the TYPES OF DISPERSION.
a. List and describe the 3 types of dispersion.
Clumped = organisms stay in packs, herds, schools, etc.
b.
c.
Uniform = organisms stay equal distances from each other (everyone has their own
space)
Random = some organisms are close and some are far (there is no pattern to the
location)
What are the benefits of each of the 3 types of dispersion?
Clumped = organisms help each other to stay alive if they’re prey, help each other
to hunt if they’re predators, and for social companionship
Uniform = territorial organisms that fight to preserve their own space, food, water,
etc.
Random = there is no real benefit to this dispersion. It is plants that are
wind/water/animal distributed so they can’t choose where they go. they have to be
able to survive close to others or far away.
Which is the most/least common?
Clumped = most common because they help each other
Random = least common because there is no survival benefit
19. Answer the following questions concerning the POPULATION GROWTH.
d. How are exponential and logistic growth different?
Exponential = UNREGULATED growth. Population density does not affect it. It is
IDEALIZED growth where the population DOUBLES every generation.
Logistic = Growth that is affected by population density. The population reaches a
CARRYING CAPACITY where there are LIMITING FACTORS (SPACE, FOOD,
WATER, ETC.) that slow the population growth rate to 0 (equal birth and deaths)
e. Draw a graph showing each of the population growth methods listed in part a. against
time.
LOGISTIC GROWTH
EXPONENTIAL GROWTH
What happens to the growth rate once it reaches the carrying capacity?
Equals 0 (equal birth and death)
g. What are limiting factors?
Factors that LIMIT the population size (Size, Space, Food, Competition, Disease,
Etc.)
20. List and explain the three types of survivorship curves.
Type 1
 Survive to old age.
 Humans, large mammals
 Produce few offspring & provides good care.
Type 2
 Likelihood of death constant throughout life.
 Lizards, rodents, birds.
 A straight line on a graph = constant rate
 Any prey
Type 3
 Low survival rate for the very young.
 Oysters, invertebrates, seed plants
 Produce large numbers of offspring & little care.
f.