Bioaccumulation in plants and animals.ppt

Bioaccumulation

1. Starter; Write down as many food chains
as you can from this food web.
leaves and berries
earthworm
robin
sparrowhawk
mouse
dandelion
rabbit
stoat
owl

2. Starter; Write down as many food chains
as you can from this food web.
leaves and berries
earthworm
robin
sparrowhawk
mouse
dandelion
rabbit
stoat
owl
(How many carnivores are in the food web? How many herbivores? Name them.)

3. Starter; Write down as many food chains
as you can from this food web.
leaves and berries
earthworm
robin
sparrowhawk
mouse
dandelion
rabbit
stoat
owl

4. Starter; Write down as many food chains
as you can from this food web.
leaves and berries
earthworm
robin
sparrowhawk

5. Today’s learning objectives!
1.Name a pesticide which will
not break down in the
environment.
2.Describe how pesticides can
kill other organisms.
3.Explain advantages of using
biological control over
pesticides.

6. Toxic food chains
•What are pesticides used for?
•DDT, a useful pesticide, was found to have lots
of toxic effects on the environment, especially
birds.
•DDT is not easily broken down by the
environment.

8. 1.Each leaf receives one “dose” of DDT when sprayed.
2.Each worm eats 3 leaves, and receives 3 doses of DDT.
3.Each robin eats 2 worms.
4.Each sparrowhawk eats 2 robins.
5.How many doses of DDT does the sparrowhawk eat?
6.If they eat enough DDT, birds lay eggs with very thin
shells, which break before they are ready to hatch. How
might this effect the sparrowhawk population, and the
other members of the food chain?
Bioaccumulation

10. Today’s learning objectives!
1.Name a pesticide which will
not break down in the
environment.
2.Describe how pesticides can
kill other organisms.
3.Explain advantages of using
biological control over
pesticides.

14. Today’s learning objectives!
1.Name a pesticide which will
not break down in the
environment.
2.Describe how pesticides can
kill other organisms.
3.Explain advantages of using
biological control over
pesticides.

15. What do you think these people are doing?
Why?

16. Let’s play ...
true or false

17. Pesticides reduce crop yield.
False

18. Bioaccumulation is where the first
organism to swallow pesticide is the
most damaged.
False

19. Biological control agents are organisms
released into a food web to control the
amount of another species.
True

20. Aphids are an example of a biological
control agent.
False

21. Poisons can be passed through food
chains and get more concentrated at
each step.
True

22. Are green plants important?
True

23. Do all living things die?
True