1. 4/16 & 4/17- 7th Grade Agenda Learning Objective: Learn about worms
Collect HW: Reading & Notetaking p
Earth Worm Observation Lab
Pass back graded HW & Test & Grade Print Out
Textbook Reading 417 – 421
HW: Reading & Notetaking
HW: Signed Grade Printout

2. Reflection
Prompt: Write 3 questions that you have about earthworms.

3. Sea anemone and many circular animals exhibit R______ S_______
adial
ymmetry
What are some characteristics of Radial Symmetry Animals?
Do not have distinct front or back ends
Lives in the ocean
Senses their environment in all directions

4. The balanced arrangement of a butterfly’s body is called B_______ S________
ilateral
ymmetry
What are some characteristics of Bilateral Symmetry Animals?
Larger & More complex than radial symmetry animals
Moves more quickly
Sense organ in the front

5. Usually Perfect Symmetry is not attractive
Right Side
Symmetrical
True Portrait
Left Side
Symmetrical

6. Usually Perfect Symmetry is not attractive
True Portrait
Left Side
Symmetrical
Right Side
Symmetrical

7. Is a Sponge an animal or a plant?
Sponge is an animal
Although it cannot move around from place to place sponge take food into their bodies

8. What do sponges eat? Tiny organisms such as bacteria and protists
Sponge gets its oxygen from water
Network of spikes support the sponge

9. Sponge Larva Sponge reproduce asexually and sexually
Sponges do not have separate sexes
At any one time of the year, some sponges are producing eggs and others are producing sperms

10. What are Cnidarians?

11. Jellyfish Facts They are not used to make Jelly 98% Water
No Heart or Blood
Most don’t have a brain (except Box Jellyfish)
Most only detect light. Some have 24 eyes (Box Jellyfish)
When stung, Vinegar (not urine) is the best treatment
Irukandji Jellyfish (size of fingernail) can kill you with a single sting.

12. More on Cnidarians Unlike sponges, cnidarians have specialized tissues
Muscle like tissues for swimming
Anemones stretch out

13. How does cnidarians obtain and digest food?
Cnidarians captures its prey by using its stinging cells to inject venom
Then the cnidarian’s tentacles pull the prey animal to its mouth
From there the food passes into a body cavity where it is digested.

14. How are coral reefs made?
Built by cnidarians
Free swimming coral larva attaches to a solid surface ( broken shell, sunken ship)
The coral polyp produces a hard, stony skeleton around its soft polyp body
Over thousands of years, as live corals add their skeletons, the reef grows

15. What are the major type of worms
Flatworms
Roundworms
Segmented Worms

16. Lifecycle of a tapeworm

17. An organism that lives inside or on another organism and takes its food from that organism is a P_______
arasite

18. Do worms have brains? Yes
They also have a heart, digestive tract and reproductive organs

19. How do Earthworms Mate?
Earthworms are hermaphroditic meaning each worm has organs of both sexes.
One worm has to find another worm in order to mate

20. Do earthworms have eyes?
They do not have eyes
But they do possess light- and touch-sensitive organs (receptor cells) to distinguish differences in light intensity and to feel vibrations in the ground.

21. What is the "bump" in the middle of the earthworm?
The bump is the clitellum.
It contains the gland cells which secrete a slimy material (mucus) to form the cocoon which will hold the worm embryos.

22. Earthworm Cocoons

23. Can earthworms regenerate themselves?
Yes, but only the front or head end of the earthworm will survive and the amputated tail portion will die.

24. Virtual Dissection of Earthworm

25. What is the difference between front end and back end?
Front End (Anterior)
Back End (Posterior)

26. What is the difference between top side and bottom side?
Top side (Dorsal)
Bottom side (Ventral)

27. Dissecting the earthworm

28. Internal View

29. Aortic Arches (Primitive Heart)

30. Cross section view

31. Does earthworm have bilateral or radial symmetry?
Bilateral Symmetry