Across 6. System that produces offspring and regulates sexual characteristics. 7. System that protects the body, transfers heat, and houses sensory receptors. 8. System that circulates the blood throughout the body. 11. A pair of air filled organs that expand and contract and is part of the respiratory system. 12. Bony structure that surrounds your brain. 16. Nodes that make up the lymphatic system. (2 Words) 18. System that circulates hormones around the body to control functions and maintains homeostasis. 20. System that works to help maintain circulatory system as well as housing cells responsible for immunity. 21. Control system of body that controls heart rate, maintains blood oxygen levels, and is responsible for taking in information via "senses". 22. System that provides body structure and support.

Down 1. Glands in the endocrine system that are responsible for releasing adrenaline. (2 Words) 2. Muscles found on the front part of your upper arm. 3. Major organ of the digestive system that digests food. 4. Female reproductive organs that protect and release eggs along with secreting hormones. 5. The largest organ that protects your internal organs from disease, regulates body temperature, and holds nerve endings. 9. System that acts as the ventilation system for the body that takes in oxygen and releases carbon dioxide from blood. 10. System that allows for movement. 13. Organ that is part of the excretory system and holds urine. 14. The major organ of the nervous sytem. 15. System that filters wastes from blood and maintains bodies internal nutrient balances as well as rids body of wastes via the urethra. 17. System that breaks down macromolecules and absorbs necessary nutrients. 19. Major organ of the circulatory system that pumps blood throughout your body.