Maintaining a Balance
1. What are enzymes? Identify their role in metabolism.
2. Enzymes are made up of ____________, _____________, ______________ and ________________. 3. Enzymes are large __________ that are coiled up to form an ____________ __________. 4. The molecule that the enzyme acts on is called the ______________. 5. Use a model to illustrate how enzymes work.
6. Explain how enzymes are specific.
7. Using the pH scale, identify how the pH can be used to describe the acidity of a substance.
8. Define intracellular.
9. Give an example of a chemical equation involving an enzyme:
10. With reference to a first hand investigation you have performed, describe the effect of: a) Temperature on the activity of an enzyme:
b) pH on the activity of enzymes:
c) Change in substrate concentrations on the activity of the enzyme:
11. Why is the maintenance of a constant internal environment important for metabolic efficiency?
12. Describe homeostasis.
13. The two stages of homeostasis are:
1) __________________________________________ 2) __________________________________________
14. Explain the first stage of homeostasis:
|STIMULUS |RECEPTOR AND EXAMPLE | |Light | | | |Thermoreceptor, e.g. skin. | |Sound, touch, pressure, gravity | | |Electrical fields, magnetic fields | | | |Chemoreceptor, e.g. oxygen |
16. Explain the second stage of homeostasis.
17. Draw a model of homeostasis:
18. Outline the role of the nervous system in detecting and responding to environmental changes.
19. Identify the broad range of temperatures over which life is found compared with the narrow limits for individual species such as sugar cane; seeds, lichens and mosses; and Bogong moths.
|ORGANISM |CHANGE IN TEMPERATURE |RESPONSE |HOW RESPONSE ASSISTS TEMPERATURE | | | | |REGULATION | |Superb parrot (endotherm) | | | | |Kangaroo (endotherm) | | | | |Eucalyptus (ectotherm) | | | | |Central netted dragon | | | | |(ectotherm) | | | |