IBDP ESS Y12 Ecology

How does energy enter an ecosystem?

• sunlight

• soil

• animals

An important abiotic factor in ALL ecosystems is the 

• ecology
• climate
• plants
• animals

Autotrophs are organisms that

• rely on other organisms for their energy & food supply.
• consume plant & animal remains and other dead matter.
• use energy they take in from the environment to convert inorganic molecules to organic molecules.
• obtain energy by eating only plants.

The total mass of living tissue at each trophic level can be shown in a(n)

• energy pyramid
• pyramid of numbers
• biomass pyramid
• biogeochemical cycle

Why are food chains, such as the one shown, limited to 4-5 organisms?

• There are not more organisms in the ecosystem
• Organisms must share resources
• Energy transfers are inefficient
• They are only limited when organisms are living on land.

At which trophic level can you find an herbivore?

• 1st Level

• 2nd Level

• 3rd Level

• 4th Level

Why are decomposers necessary?

• Because we compose too much...

• To take basic materials and make them more complex...

• To take complex materials and break them down to basic stuff...

• So demusic can be really good...

When energy is wasted or lost, it is in the form of what?

• Carbon Dioxide

• Heat

• Water

When humans burn fossil fuels, most of the carbon quickly enters the                       as carbon dioxide.

• Water
• Atmosphere
• Sun
• Air

How do living organisms return carbon to the atmosphere in the carbon cycle?

• respiration and photosynthesis
•  decomposition and respiration