Chapter 4 | Metabolism and Cellular Respiration
- Does physical exercise involve anabolic and/or catabolic processes? Give evidence for your answer.
- Name two different cellular functions that require energy that parallel human energy-requiring functions.
- Explain in your own words the difference between a spontaneous reaction and one that occurs instantaneously, and what causes this difference.
- Describe the position of the transition state on a vertical energy scale, from low to high, relative to the position of the reactants and products, for both endergonic and exergonic reactions.
- Imagine an elaborate ant farm with tunnels and passageways through the sand where ants live in a large community. Now imagine that an earthquake shook the ground and demolished the ant farm. In which of these two scenarios, before or after the earthquake, was the ant farm system in a state of higher or lower entropy?
- Energy transfers take place constantly in everyday activities. Think of two scenarios: cooking on a stove and driving. Explain how the second law of thermodynamics applies to these two scenarios.
- Do you think that the EA for ATP hydrolysis is relatively low or high? Explain your reasoning.
- Why is it beneficial for cells to use ATP rather than energy directly from the bonds of carbohydrates? What are the greatest drawbacks to harnessing energy directly from the bonds of several different compounds?
- Nearly all organisms on earth carry out some form of glycolysis. How does that fact support or not support the assertion that glycolysis is one of the oldest metabolic pathways?
- Red blood cells do not perform aerobic respiration, but they do perform glycolysis. Why do all cells need an energy source, and what would happen if glycolysis were blocked in a red blood cell?
- What is the primary difference between a circular pathway and a linear pathway?
- How do the roles of ubiquinone and cytochrome c differ from the other components of the electron transport chain?
- What accounts for the different number of ATP molecules that are formed through cellular respiration?
- What is the primary difference between fermentation and anaerobic respiration?
- Would you describe metabolic pathways as inherently wasteful or inherently economical, and why?
