Biodegradable and non-biodegradable

The idea

Substances broken down by biological processes are biodegradable; those that are not are non-biodegradable, and may persist inertly in the environment for a long time or harm members of the ecosystem.

Two kinds of waste

A banana peel and a plastic wrapper are thrown on the ground in a park.

What happens to them after a long time?

• The peel is broken down, the wrapper stays
• Both are broken down
• Neither is broken down

Sort the waste

Tap a bin for each card.

Broken down or not

Some substances are broken down by biological processes, such as the work of bacteria and fungi. These are biodegradable. Others are not broken down in this way. These are non-biodegradable. They may stay in the environment for a long time, or they may harm the members of the ecosystem.

Substances broken down by biological processes are biodegradable; those that are not are non-biodegradable, and may persist inertly in the environment for a long time or harm members of the ecosystem.

Notes

Waste broken down by biological processes is biodegradable; waste that is not is non-biodegradable.

Check yourself

What are substances called that are broken down by biological processes?

What may a non-biodegradable substance do in the environment?

Which of these is non-biodegradable?

According to the book, what has made much of our waste non-biodegradable?

• Biodegradable — correct. Yes!
• Non-biodegradable. Non-biodegradable substances are the ones that are not broken down by biological processes.
• Inert. A substance that is inert simply persists. Substances broken down by biological processes are biodegradable.
• Be broken down quickly by bacteria and fungi. Substances broken down by bacteria and fungi are biodegradable.
• Persist inertly for a long time or harm members of the ecosystem — correct. Yes!
• Turn into food for the producers. Non-biodegradable substances are not broken down by biological processes, so they do not return as substances for plants.
• Dead remains of plants. Decomposers break down dead remains, so they are biodegradable.
• Waste products of animals. Decomposers break down the waste products of organisms, so they are biodegradable.
• Plastics — correct. Yes!
• Changes in packaging — correct. Yes!
• Changes in attitude, which have made things disposable. Changes in attitude have made more things disposable, which adds to the amount of waste. The book links the non-biodegradable part to packaging.
• Improvements in life-style, which have increased the amount of waste. Improvements in life-style resulted in greater amounts of waste. The book says that changes in packaging made much of it non-biodegradable.