Exploring Food Chains and Webs

The lecture covers energy flow in ecosystems, focusing on food chains, food webs, and ecological pyramids. It explains how energy moves from the sun to producers and consumers, the role of decomposers, and the impact of disturbances in food webs. The concept of trophic levels and the types of ecological pyramids—energy, biomass, and numbers—are also discussed.

What is the initial source of energy in an ecosystem?

• Decomposers

• Producers

• Consumers

• The Sun

Tags

NGSS.MS-LS2-3

In a food chain, what do the arrows represent?

• The direction of energy flow

• The size of the organisms

• The number of organisms

• The speed of energy transfer

Tags

NGSS.MS-LS1-6

NGSS.MS-LS2-3

Which of the following is always the first trophic level in a food chain?

• Omnivores

• Producers

• Carnivores

• Herbivores

What term is used to describe the first consumer in a food chain?

• Primary consumer

• Secondary consumer

• Tertiary consumer

• Quaternary consumer

How does a food web differ from a food chain?

• A food web shows multiple feeding relationships

• A food web does not include decomposers

• A food web only includes producers

• A food web is simpler than a food chain

What role do decomposers play in an ecosystem?

• They produce energy from the sun

• They consume herbivores

• They break down dead and decaying organisms

• They compete with producers for nutrients

Tags

NGSS.MS-LS2-3

What can cause a disturbance in a food web?

• Introduction of a new species

• All of the above

• A disease affecting a population

• A change in weather patterns

Tags

NGSS.MS-LS2-3

NGSS.MS-LS2-4

What is the primary focus of an ecological pyramid?

• The speed of energy transfer

• The size of the organisms

• The distribution of energy or matter at each trophic level

• The number of species in an ecosystem

Tags

NGSS.MS-LS2-3

In a pyramid of energy, what percentage of energy is typically transferred from one trophic level to the next?

• 25%

• 10%

• 100%

• 50%

Tags

NGSS.MS-LS2-3

Which type of ecological pyramid shows the mass of organisms at each trophic level?

• Pyramid of energy

• Pyramid of numbers

• Pyramid of species

• Pyramid of biomass