Understanding Food Webs and Energy Flow

The video discusses food webs, explaining how energy flows through ecosystems. It covers the direction of arrows in food webs, the 10 percent rule of energy transfer, and how changes in one part of the web can impact the entire system. The video uses examples to illustrate these concepts and concludes with a summary of the key points.

What is a food web?

• A representation of the water cycle

• A linear sequence of organisms each feeding on the next

• A network of interconnected food chains

• A diagram showing the flow of energy in an ecosystem

What is the primary source of energy in a food web?

• The sun

• Producers

• Consumers

• Decomposers

In a food web, what do the arrows represent?

• The lifespan of the organism

• The direction of energy flow

• The size of the organism

• The speed of energy transfer

What does the 10 percent rule state?

• 10 percent of organisms survive each year

• 10 percent of the ecosystem is made up of producers

• 10 percent of energy is transferred to the next trophic level

• 10 percent of the food web is aquatic

What happens to the energy as it moves up trophic levels?

• It decreases by 90 percent

• It remains constant

• It doubles

• It increases by 10 percent

What happens to the energy when mollusks eat algae?

• 50 percent is transferred

• 10 percent is transferred

• 90 percent is transferred

• 100 percent is transferred

If a new predator is introduced to a food web, what is likely to happen?

• Only the predator population is affected

• The entire food web is impacted

• Only the prey population is affected

• The entire food web remains unchanged

How does a decrease in insect population affect the food web?

• It increases the insect population

• It increases the bird population

• It decreases the bird population

• It has no effect on the food web

What is the result of fewer insects eating the lawn?

• The lawn dies

• The lawn remains unchanged

• The lawn becomes healthier

• The lawn becomes less green

What is the effect of a new family of birds moving into an ecosystem?

• The bird population decreases

• The bug population decreases

• The ecosystem remains stable

• The bug population increases