1. Big Idea #2: Cellular Processes and Communication Biological systems utilize free energy and molecular building blocks to grow, to reproduce, and to maintain dynamic homeostasis.

2. Questions to ponder… What is human body temperature in Celsius? Is there an average body temperature for animals? How does the body use feedback order to maintain a constant body temperature? Can we connect properties of water to thermoregulation?

3. What is the optimal temperature range? Mammals 36-38 C ; Birds 39-42 C Amphibians & Reptiles: varies greatly Thermoconfomers: Fish: within 1-2 C of surrounding water Invertebrates: with some exceptions (bees)

4. Role of Water Properties Define High specific heat? Explain in terms of the structure of water. Apply Air vs. water temp? Connect to marine vs. land animals? Role in daily and seasonal change? Animal adaptations?

5. Ectotherms Heat transfer occurs easily Metabolic rate has little effect on body temperature Invertebrates, fishes, amphibians, reptiles

6. Endotherms  Body warmer than the environment  Due to high metabolic rate  Birds, mammals, bees and moths

7. Why aren’t they called cold blooded or warm-blooded?

8. Who has an advantage? Endotherms Can perform vigorous activity for long periods of time. Can tolerate winter and hot environments Ectotherms: Cost of food Human: Metabolic resting rate of 1300 kcal/day Alligator: Metabolic resting rate of 60 kcal/day

9. Investigating a Negative Feedback Loop Stimulus Sensor Set Point Response Negative Feedback

10. Evaporative Cooling Panting, Sweating, Bathing Water absorbs heat when it evaporates which has a cooling effect. Summer topor: low metabolism due to high temperatures Daily topor: animals go inactive when temperature isn’t ideal

11. Vasodilation/Vasoconstriction Vasodilation: increase in the diameter of superficial blood vessels (cools) Vasoconstriction: decrease in the diameter of blood vessels (warms)

12. Metabolic Change Movement, shivering increase muscle contraction. Heat is a waste product of metabolism NST (nonshivering thermogenesis) Brown Fat: tissue specialized for using mitochondria for heat production instead of ATP

13. Human Thermoregulation

14. Formative Assessment

15. Part of Feedback Loop? Cross country skiing on a warm day. You have dressed in layers and you have just climbed your first incline. Part of Feeback Loop? Oops…you didn’t dress for the weather. You are out cross country skiing and stopped to take a break. Suddenly, clouds cover the sky and the wind picks up. You have forgotten your hat and gloves.

16. What is postive feedback then? Does positive feedback happen? Let’s look at an example with water and climate change.

17. More feedback loops Preview the role of the thyroid: How does the brain and the thyroid control metabolism? How does the thyroid and parathyroid control blood calcium?

18. More on Water Properties For each property of water: DescriptionStructure Meets Function Implications What is the property? How does the structure of water cause this property? How does this impact life on Earth? -At the organism level? -At the ecological level?