1. Explain the goal and mechanisms of homeostasis. 2. Define thermoregulation, differentiating between ectotherms and endotherms. 3. Define osmoregulation, and discuss the excretory system. 4. Summarize the purpose of the digestive system, and name its primary components. 5. Summarize the purpose of the respiratory system, and name its primary components. 6. Summarize the purpose of the circulatory system, and name its primary components. 7.Summarize the purpose of the endocrine system and the role of hormones. 8. Summarize the purpose of the skeletal system and its two divisions. 9. Summarize the purpose of the muscles, and identify the three types of muscle tissue. 10. Discuss the basic structure of a neuron. 11. Explain the central and peripheral nervous systems. 12. Describe viruses and how they replicate. 13.Discuss the human immune system and its role in defending against threats. 14.Explain the benefits of biodiversity. 15.List the threats to biodiversity.