1. Annelids Tube shaped worms with rings
Segmented Worms
Annelids
Tube shaped worms with rings

2. New Words Setae- bristle-like structures
Crop- a sac used for food storage
Gizzard- a muscle that grinds up bits of soil and organic matter
Anterior- front end of an organism
Posterior –back end of an organism
Hermaphrodites- organisms that produce sperm & eggs in the same body

3. Segmented Worms Use setae to hold onto soil and move
Have bilateral symmetry
Body cavity that holds organs
Two body openings (mouth & anus)
Annelids are found in freshwater, saltwater & moist soil

4. Earthworm Body Systems
Have a definite anterior- front end
Have a definite posterior- back end
Each body segment (except the first and last) have a pair of setae & 2 sets of muscles

6. Earthworms burrow through soil
They take soil into their mouth

7. They get energy from soil & other organic matter found in the soil
The soil moves to the crop and into the gizzard to be ground, broken down, and the nutrients absorbed my the blood

8. Waste leave the worm through the anus

9. A thick ring structure used in reproduction
Clitellum
A thick ring structure used in reproduction

10. When earthworms take in soil, they provide spaces for air and water to flow through it and mix the soil

12. Their wastes pile up a the openings to their burrows
We call these wastes “castings”
The castings help fertilize the soil

13. Vermicompost

14. We call these casting VERMICOMPOST
They are used as an organic fertilizer in gardens

15. Earthworms have a closed circulatory system

17. Two blood vessels run from the top to the bottom of their bodies
They have a heartlike structure called “aortic arches” which pump blood to the body

18. Oxygen and carbon dioxide are exchanged through their skin
They DO NOT have gills or lungs!
You can suffocate an earthworm by touching it with dry hands or by wiping off their mucous layer
However – they cannot survive submerged in puddles of water either
It is a delicate balance
Watch them

19. Earthworms have a small brain in their front segment of their body
Nerves in each segment form a main nerve cord that connects to the brain

20. Explain this adapatation
Earthworms respond
To light
Temperature
moisture
Explain this adapatation

22. Earthworms are Hermaphrodites
They have body male and female reproductive structures in one body
One individual CANNOT fertilize its own eggs
It must receive sperm from another earthworm in order to reproduce

24. Earthworms mating

25. Why would earthworms be healthy to have in a garden or compost pile?

26. Are you ready to dissect?