1. CH 24 WHAT IS AN ANIMAL?

2. CHARACTERISTICS OF ALL ANIMALS
Eukaryotic
Multicellular (metazoans)
Specialized cells (tissues & organs)
Ingestive heterotrophs

3. SEXUAL REPRODUCTION (MOST)
Sperm + Egg = Zygote
Cleavage -> zygote divides
Embryo -> an organism in the early stages of development

4. CELL LAYERS (MOST HAVE THREE)
Ectoderm - outer layer (skin & nervous tissue
Endoderm - inner layer (digestive organs)
Mesoderm - middle layer (muscles, circulatory, excretory and respiratory systems

5. SYMMETRY Radial - round, or sphere shaped
Bilateral - R & L halves form mirror images
Asymmetrical – no definite shape

6. BODY PLANES Dorsal - back surface Ventral - belly surface
Anterior - top (head)
Posterior - tail end

7. BODY CAVITIES Coelum - fluid-filled cavity / mesoderm (earthworms)
Acoelomate - no body cavity (flatworms)

8. STRUCTURES FOR SUPPORT AND DEVELOPMENT
Vertebrates - have an internal backbone - (endoskeleton)
Invertebrates - lack a backbone - most have an exoskeleton

9. MICROSCOPE PROCEDURES

10. Parts
of the
Microscope

11. 1. Carry with both hands

12. 2. Unwrap and plug in the cord. Turn on the light
2. Unwrap and plug in the cord. Turn on the light. Turn the coarse and fine adjustment knobs until the stage is close to the objective.

13. 3. Start on low power 4X which = 40X or 10X which = 100X NOT 40X which = 400X

14. 4. Put slide on stage - Apply stage clips

15. 5. Turn coarse adjustment knob ¼ – ¾ turn. Find and focus.

16. 6. Make sure the specimen is in the middle of the field of view before switching to high power.

17. 7. Flip the high power objective lens (400x) into place
7. Flip the high power objective lens (400x) into place. Refocus using ONLY the fine adjustment.

18. If you lose your specimen when switching to high power you must refocus on low power again before switching to high power.

19. 8. Remove the slide when finished.

20. 9. Turn off the light. Return to low power.

21. 10. Wrap cord correctly. Show microscope to your teacher
10. Wrap cord correctly. Show microscope to your teacher. Return microscope to cart.