Body Systems

3. A strong muscle that acts as a pump
6. A long tube where most digestion happens and nutrients are absorbed
10. The thick middle layer; contains blood vessels, nerves, hair follicles, and glands
11. Tubes that carry blood away from the heart
13. Absorbs water from remaining waste and turns it into stool
15. The fluid that moves through the system
18. A long bundle of nerve tissue that runs down the back, connecting the brain to the rest of the body
20. Controls thought, memory, emotion, touch, vision, breathing, and every other process that regulates our body
22. The thin, waterproof outer layer; acts as the primary barrier against germs
24. A sac that mixes food with strong acids and enzymes

1. Produces bile to help digest fats
2. A specialized layer of fibrous connective tissue that surrounds, supports, and separates individual muscles and muscle groups
4. Stores bile until the body needs it for digestion
5. Tiny, thin blood vessels
7. Chews food and uses saliva to start breaking down carbohydrates
8. Made of hard keratin; protect the tips of fingers and toes
9. Tough bands of connective tissue that firmly attach skeletal muscles to bones
12. Made of keratin; helps with insulation and sensory input
14. A muscular tube that pushes food down from the throat to the stomach
16. The deep fatty layer; insulates the body and cushions organs
17. Includes sweat glands for cooling and oil glands for lubrication
19. Tubes that bring blood back to the heart
21. Pathways from the nervous system that stimulate muscle fibers to contract
23. Secretes digestive enzymes and juices to process proteins, fats, and sugars