Food Webs & Chains
In a food chain, arrows point in the direction that ____ moves from the organism being eaten to the organism that eats it.
Energy
What trophic level contains the greatest amount of available energy in an energy pyramid.
Producers
These organisms make their own food, often by using sunlight in photosynthesis.
Producers
A forest fire destroys many plants. What effect will this have on consumers?
Less energy/food available
What do decomposers do?
Eat dead organisms of any level.
In the chain pond algae → crustaceans → small fish → large fish, the small fish is this type of consumer.
Level 3: Secondary Consumer
This percentage of energy is transferred from one trophic level to the next.
10%
An animal that eats plants (herbivore) is this type of consumer.
Primary Consumer
In the chain pond algae → crustaceans → small fish → large fish, a pesticide sharply reduces the amount of ccrustaceans. What would be the effect of this?
The amount of fish will decrease.
List the trophic levels in order.
Lvl 1- Producer
Lvl 2- Primary Consumer
Lvl 3- Secondary Consumer
Lvl 4- Tertiary Consumer
A diagram that combines several connected food chains to show multiple feeding pathways is this.
Food Web
This is the original energy source for most ecosystems, entering food webs when producers capture its energy.
The Sun
These organisms break down dead organisms and wastes, returning nutrients to the environment.
Decomposers
A new predator is introduced to an island and begins eating native lizards. The most direct expected change is a decrease in this population.
Lizards
How do producers get food/energy?
Photosynthesis
What is transferred between organisms in a food web/chain?
Energy and Matter
Most energy not transferred to the next trophic level is used for life processes or released in this form.
Thermal energy/Heat
In a meadow, grass is eaten by deer, and deer are eaten by wolves. What trophic level are the wolves?
Secondary Consumer
What would have the greatest effect on the flow of enery in a food chain?
Decrease in sunlight
How do consumers get food/energy?
Eating other living things.
In a food web, grass is eaten by deer, and deer are eaten by wolves. The amount of grass decreased, causing the amount of deer and wolves to decrease. Why did this happen (use vocabulary)?
Organisms in a food web are dependent on one another because they are interconnected.
If plants store 8,000 units of energy, this many units are expected to reach primary consumers under the 10% rule.
800 calories
A plant disease reduces the amount of vegetation in a grassland. Deer that feed on the vegetation decline, followed by wolves that hunt deer. This ecosystem principle helps explain the connected population changes.
Interdependence
Wolves are introduced to a forest where deer have become abundant. Over time, wolves increase and deer decline. This evidence supports the inference that wolves and deer have this relationship.
Predator-prey
In a pond, algae are eaten by insect larvae, which are eaten by small fish, which are eaten by large fish. A chemical spill kills most of the algae. Predict one likely effect on the food web and explain why.
The insect-larvae population may decline because algae are their food source, and populations of fish that depend on those larvae may also decline