Trophic Levels
Which would most likely be at the top of a food chain?
A. gazelle
B. grass
C. bacteria
D. lion
D. lion
Which of the following are not producers?
A. sunflowers
B. mushrooms
C. algae
D. phytoplankton
B. mushrooms
Which nutrient is cycled through limestone, fossil fuels, plants, ocean shells, living organisms, and the atmosphere?
Carbon
______________ succession occurs where no soil exists.
primary
What other method besides nitrogen-fixing bacteria converts nitrogen in the atmosphere to nitrates in the soil?
lightning!
A ____________ ____________________ is one of the steps in a food chain or food pyramid, such as producers and primary, secondary, or tertiary consumers.
trophic level
Name the products of cellular respiration.
- carbon dioxide
- water
- energy
Name the nutrient that does not cycle through the atmosphere.
phosphorus
Which of the following would most likely be a pioneer species?
A. moss
B. beavers
C. ferns
D. earthworms
A. moss
Where do bacteria and tube worms living by hydrothermal vents deep in the ocean get their energy from?
Bacteria use Hydrogen Sulfide instead of sunlight; tube worms are dependent on the bacteria
Give three possible interactions on a food web of your local pond.
frogs eat flies
spiders also eat flies
herons eat frogs
What three things do plants need to make organic molecules?
- water
- carbon dioxide
- sunlight
How does nitrogen in the atmosphere become available for plants to use?
nitrogen-fixing bacteria convert nitrogen into ammonia in the soil
A forest destroyed by fire may be restored through ____________ succession.
secondary
Name the gas that dissolves in seawater and increases its acidity.
Why is there a limit on the number of trophic levels in an ecosystem?
Energy is lost as heat at each trophic level.
Give an example of each of the following:
- herbivore
- omnivore
- carnivore
- decomposer
herbivore = rabbit
omnivore = bear
carnivore = lion
decomposer = bacteria
Describe how the excessive use of fertilizers on a farm can impact a community of fish in a river many miles away.
1. excess fertilizer is washed into a stream
2. the stream pours into the river
3. fertilizers cause algae to bloom in the river
4. the algae die
5. bacteria decomposes the algae and uses up oxygen
6. the fish die
What species would you expect to find in the climax community after old-field succession?
mature trees
Give two reasons why forest fires can benefit an ecosystem.
- clear out old brush
- remove dead trees
- allow new shoots to grow that are food for certain organisms
Biomagnification describes how a chemical accumulates in upper levels of a food chain. Describe how this relates to DDT and the bird population.
Birds eat insects poisoned by DDT and accumulate the poison in their body tissues. They may lay fragile eggs or die before reproducing.
Autotrophs are also known as ________________, and heterotrophs are also known as ________________.
producers, consumers
How do dead organisms contribute to the carbon cycle?
dead organisms decompose into organic matter that is compressed over time to form fossil fuels
Name a human activity that sets the stage for primary ecological succession.
building an asphalt parking lot
Lichens form from the symbiotic relationship between ___________ and _____________.
algae (or cyanobacteria), fungi