Explain the energetic advantage of coupling exergonic reactions to endergonic
Chapter 8 Assignment:
For this assignment, you will answer the following questions:
1. State the first and second law of thermodynamics in your own words.
2. You can think of a chemical bond sort of like two magnets sticking together. The positive pole of one magnet is attracted to the negative pole of the other. If you move them to each other they will naturally stick together (it won’t require any energy to get them to do so). Once the magnets are joined it would require energy (the ability to do work= a force applied over a distance) to separate them. Use this analogy to answer:
a) Does making chemical bonds release or require energy? Why? How do you know?
b) Does breaking chemical bonds release or require energy? Why? how do you know?
c) Provide a real-life example for chemical bonds releasing or breaking bonds in our body.
3. Explain the energetic advantage of coupling exergonic reactions to endergonic
reactions. Use for example the ATP-ADP molecule.
4. Organisms are endergonic systems. What are the exergonic reactions that provide
living systems with energy (give two examples)?
5. Explain in your own words, how the “lock-and-key” model compares with an enzyme’s function?
6. Choose one example below and explain how it will affect an enzyme’s structure and function.
a) Substrate concentration
d) salt concentration
e) cofactors and coenzymes