Across
- 2. deficiency of red blood cells, causes weakness
- 3. blood vessels carry blood towards the heart
- 4. relating to the heart
- 5. responsible for transporting oxygen from lungs to body
- 8. releases digestive enzymes and regulates sugar levels
- 10. organisms which lives off of or in another
- 11. thick walled part of a birds stomach which grinds food
- 12. muscular pouch near the throat of birds
Down
- 1. single celled organism which causes diseases in animals
- 3. given to stimulate the immune system and prevent disease
- 6. muscular organ, pumps blood through circulatory system
- 7. protective way the body signals the immune system to heal
- 9. blood vessels carry oxygenated blood away from the heart to body