1 Why is it important that the body systems are kept in balance?

2 Why is it important that the brain prioritizes the importance of the incoming stimuli?

3 Using an example, briefly explain why homeostasis often involves more than one body system:

1 How does the behavior of a negative feedback system maintain homeostasis?

2a From the diagram of the stomach emptying, name the receptor:

2b From the diagram of the stomach emptying, name the effector:

2c From the diagram of the stomach emptying, name the response:

2d What is the steady state for this example?

1a Why is positive feedback much less common than negative feedback in body systems?

1b Why can positive feedback be dangerous if it continues on for too long?

1c How is a positive feedback loop normally stopped?

2a Name the regulatory factor in childbirth:

2b What event brings an end to the positive feedback loop in childbirth?

1a Where is the temperature regulation center in humans located?1b How does it carry out this role?

2a Describe the role of skin in maintaining a constant body temperature in humans:

2b Describe the role of muscles in maintaining a constant body temperature in humans:

2c Describe the role of the thyroid gland in maintaining a constant body temperature in humans:

3 How is negative feedback involved in keeping body temperature within narrow limits?

4a Why does infection result in an elevated core body temperature?

4b What is the purpose of this?

4c Explain why a prolonged fever can be fatal:

5a What features of a newborn cause it to lose heat quickly?

5b What mechanisms do newborns have to control body temperature?

1 What is thermoregulation?

2a The graph below shows body temperature variations in a mammal (mouse) and an amphibian (frog) with change in environmental temperature. Compare and explain their different responses:

2b The blue shaded area on the graph marks the region where the energy cost of thermoregulation is lowest for the mouse. Why is the mouse using less energy to thermoregulate in this temperature range?

3 Most of thermoregulation in homeotherms occurs through physiological processes, e.g. sweating. Describe another physiological mechanism that mammals use to thermoregulate and describe its effect:

4a Describe an example of thermoregulation aided by behavior:

4b Describe an example of thermoregulation aided by physical features:

5 Describe the main difference between the thermoregulatory mechanisms of a mammal and a lizard such as Liolaemus:

6 Both humans and the Peruvian mountain lizard show a daily variation in core body temperature. Describe two main differences between these daily variations:

7 What might be the advantage to humans to allow a slight fall in core body temperature when sleeping?

1 Why must blood glucose levels be carefully controlled?

2a For low blood glucose, describe how normal blood glucose level is restored:

2b For high blood glucose, describe how normal blood glucose level is restored:

3 What is the role of the liver in blood glucose homeostasis?

4 In what way are the actions of the hormones insulin and glucagon antagonistic?

5 Relate the symptoms of type 1 diabetes to its cause and the effect on blood glucose regulation: