Across
- 1. the fushion of sperm and egg cell form a fertilized cell
- 5. a wormlike larva hatches from the egg
- 6. series of changes
- 9. simply known as the give and take relationship
- 12. vase like with tentacles
- 13. mammals with pouches
- 15. mammals that lay eggs
Down
- 2. Animals that lay eggs
- 3. animals that are born alive
- 4. animals have both reproductive organs
- 7. keeping eggs warm untik they hatch
- 8. depend on other organisms for food
- 10. white part of the eggs
- 11. simplest group of invertebrates
- 14. web overlapping food chains