Energy in Biomass

Question 1

What is biomass?

Answer 1

The mass of living/biological material in plants and animals

Question 2

What is a pyramid of biomass?

Answer 2

Model of the mass of biological material in the organisms at each level of a food chain

Question 3

Why are green plants always at the base of a pyramid of biomass?

Answer 3

Plants transfer solar energy into chemical energy. This is then passed through and used in the food chain.

They start the process of energy transfer in living organisms

Question 4

What happens at each stage of the food chain?

Answer 4

Energy is wasted or used by the organism (meaning it can’t be passed on)

Question 5

What leads to energy being lost at each stage of the food chain?

Answer 5

• Not all food can be digested. Energy is stored in faeces or urine
• Some food is used for respiration for movement and growth
• To maintain a constant temperature
• Much of the energy released from respiration is eventually transfered to the surroundings

Question 6

Is energy ever lost in the food chain?

Answer 6

No!

It is only ever transfered, although not always to the next stage of the food chain

Question 7

What are detritus feeders?

Answer 7

They start the decay process by eating dead orgamisms and producing waste

Question 8

What are decomposers?

Answer 8

Microorganisms that break down waste products and dead bodies

Question 9

Describe the decay process

Answer 9

• Detritus feeders start process by eating dead organism and producing waste
• Decomposers (decay organisms) then break down this waste
• All of the materials from the waste + dead organisms are recycled, returning nutrients to the soil

Question 10

What speeds up the decay process?

Answer 10

Warm + wet aerobic conditions

Question 11

What do many decomposers need?

Answer 11

Oxygen

Question 12

How can humans recycle waste?

Answer 12

Sewage treatment plants and compost heaps

Question 13

Complete the sentence:

Processes which use materials must…

Answer 13

…be balanced by those which release them

Question 14

What two biological processes does the recycling of carbon involve?

Answer 14

Respiration and photosynthesis

Question 15

What is the carbon cycle?

Answer 15

The cycling of carbon through the living and non-living world

It’s cyclical

Question 16

Complete the sentence:

A stable community…

Answer 16

…recylces all the nutrients it takes up

Question 17

What role does photosynthesis play in the carbon cycle?

Answer 17

It removes CO₂ from the atmosphere

Question 18

What role do green plants play in the carbon cycle?

Answer 18

They respire, which releases CO₂ back into the atmosphere

They also carry out photosynthesis, which removes CO₂ from the atmosphere

When they die, carbon is stored as organic compounds

When they are alive, it is also stored as organic compounds

When they are cut down + burnt by humans, CO₂ is released

Question 19

What role do animals play in the carbon cycle?

Answer 19

They respire, releasing CO₂ into the atmosphere

They eat green plants + transfer the carbon into their bodies

When they die, microorganisms release the CO₂ back into the atmosphere through respiration

Question 20

Draw and label a diagram of the carbon cycle

Answer 20

Question 21

What is organic waste?

Answer 21

Waste material from living organisms

e.g. garden waste

Question 22

Why should we recycle organic waste?

Answer 22

• Reduce landfil
• Reduce methane production
• Recycle minerals + nutrients in the waste

Question 23

How can organic waste be recycled?

Answer 23

• By composting in a variety of different ways
• The most efficient methods allow waste to be mixed with oxygen + moisture. Allows energy to escape by heating surroundings
• This creates ideal conditions for decay organisms to speed up process
• Gardeners may add worms + layers of garden soil to speed up the process
• Councils use shredders + large bins to compost the material