Metabolism The total of all reactions in a cell. Components of Metabolism Catabolism Breakdown of...
-
Upload
annabelle-walton -
Category
Documents
-
view
215 -
download
0
Transcript of Metabolism The total of all reactions in a cell. Components of Metabolism Catabolism Breakdown of...
![Page 1: Metabolism The total of all reactions in a cell. Components of Metabolism Catabolism Breakdown of large molecules into smaller ones Energy is released.](https://reader034.fdocuments.us/reader034/viewer/2022051622/5697c0131a28abf838cccc76/html5/thumbnails/1.jpg)
Metabolism
The total of all reactions in a cell
![Page 2: Metabolism The total of all reactions in a cell. Components of Metabolism Catabolism Breakdown of large molecules into smaller ones Energy is released.](https://reader034.fdocuments.us/reader034/viewer/2022051622/5697c0131a28abf838cccc76/html5/thumbnails/2.jpg)
Components of Metabolism
• Catabolism
• Breakdown of large molecules into smaller ones
• Energy is released
![Page 3: Metabolism The total of all reactions in a cell. Components of Metabolism Catabolism Breakdown of large molecules into smaller ones Energy is released.](https://reader034.fdocuments.us/reader034/viewer/2022051622/5697c0131a28abf838cccc76/html5/thumbnails/3.jpg)
Components of Metabolism
• Anabolism
• Building of large molecules from smaller ones
• Energy is required
![Page 4: Metabolism The total of all reactions in a cell. Components of Metabolism Catabolism Breakdown of large molecules into smaller ones Energy is released.](https://reader034.fdocuments.us/reader034/viewer/2022051622/5697c0131a28abf838cccc76/html5/thumbnails/4.jpg)
Energy Basics
• Two types—kinetic & potential
• Many forms—chemical, electromagnetic, mechanical, heat, nuclear
• Energy can be transformed from one type to another
![Page 5: Metabolism The total of all reactions in a cell. Components of Metabolism Catabolism Breakdown of large molecules into smaller ones Energy is released.](https://reader034.fdocuments.us/reader034/viewer/2022051622/5697c0131a28abf838cccc76/html5/thumbnails/5.jpg)
1st Law of Thermodynamics
• Energy can be neither created nor destroyed but it can change forms
• Energy is conserved in a reaction
![Page 6: Metabolism The total of all reactions in a cell. Components of Metabolism Catabolism Breakdown of large molecules into smaller ones Energy is released.](https://reader034.fdocuments.us/reader034/viewer/2022051622/5697c0131a28abf838cccc76/html5/thumbnails/6.jpg)
2nd Law of Thermodynamics
• Every energy transfer or transformation makes the universe more disordered.
• Entropy—The measure of the amount of disorder or randomness
![Page 7: Metabolism The total of all reactions in a cell. Components of Metabolism Catabolism Breakdown of large molecules into smaller ones Energy is released.](https://reader034.fdocuments.us/reader034/viewer/2022051622/5697c0131a28abf838cccc76/html5/thumbnails/7.jpg)
Which has more entropy???
• A cluttered closet or a well-organized closet?
• An ice cube or a glass or water?
• A gallon of gasoline or the carbon dioxide and water vapor that escape the exhaust pipe?
![Page 8: Metabolism The total of all reactions in a cell. Components of Metabolism Catabolism Breakdown of large molecules into smaller ones Energy is released.](https://reader034.fdocuments.us/reader034/viewer/2022051622/5697c0131a28abf838cccc76/html5/thumbnails/8.jpg)
There is an unstoppable trend toward randomization in nature
• Heat is a very disorganized form of energy and is the fate of all energy transformations.
• The quantity of energy in the universe is constant, but its quality is not.
![Page 9: Metabolism The total of all reactions in a cell. Components of Metabolism Catabolism Breakdown of large molecules into smaller ones Energy is released.](https://reader034.fdocuments.us/reader034/viewer/2022051622/5697c0131a28abf838cccc76/html5/thumbnails/9.jpg)
Reactions that occur spontaneously
• Increase the stability of the system
• Increase the entropy (randomness or disorder) of the system
![Page 10: Metabolism The total of all reactions in a cell. Components of Metabolism Catabolism Breakdown of large molecules into smaller ones Energy is released.](https://reader034.fdocuments.us/reader034/viewer/2022051622/5697c0131a28abf838cccc76/html5/thumbnails/10.jpg)
![Page 11: Metabolism The total of all reactions in a cell. Components of Metabolism Catabolism Breakdown of large molecules into smaller ones Energy is released.](https://reader034.fdocuments.us/reader034/viewer/2022051622/5697c0131a28abf838cccc76/html5/thumbnails/11.jpg)
Spontaneous reactions
• Release energy that can perform work
• This energy is known as free energy
• It is represented by the letter G
![Page 12: Metabolism The total of all reactions in a cell. Components of Metabolism Catabolism Breakdown of large molecules into smaller ones Energy is released.](https://reader034.fdocuments.us/reader034/viewer/2022051622/5697c0131a28abf838cccc76/html5/thumbnails/12.jpg)
Free energy is
• A measure of a system’s instability
• Systems that change to a more stable state have high free energy, low entropy or both.
![Page 13: Metabolism The total of all reactions in a cell. Components of Metabolism Catabolism Breakdown of large molecules into smaller ones Energy is released.](https://reader034.fdocuments.us/reader034/viewer/2022051622/5697c0131a28abf838cccc76/html5/thumbnails/13.jpg)
The ATP molecule
• ATP is the energy currency for cellular work.
• Cells do the following kinds of work:
• Mechanical work
• Transport work
• Chemical work
![Page 14: Metabolism The total of all reactions in a cell. Components of Metabolism Catabolism Breakdown of large molecules into smaller ones Energy is released.](https://reader034.fdocuments.us/reader034/viewer/2022051622/5697c0131a28abf838cccc76/html5/thumbnails/14.jpg)
![Page 15: Metabolism The total of all reactions in a cell. Components of Metabolism Catabolism Breakdown of large molecules into smaller ones Energy is released.](https://reader034.fdocuments.us/reader034/viewer/2022051622/5697c0131a28abf838cccc76/html5/thumbnails/15.jpg)
The ATP molecule
• Is highly organized (low entropy)
• Very unstable (negative phosphates in close proximity)
• Therefore, has a very high free energy
• ΔG = -7.3 kcal/mol for hydrolysis of ATP
![Page 16: Metabolism The total of all reactions in a cell. Components of Metabolism Catabolism Breakdown of large molecules into smaller ones Energy is released.](https://reader034.fdocuments.us/reader034/viewer/2022051622/5697c0131a28abf838cccc76/html5/thumbnails/16.jpg)
Free Energy and Equilibrium
• Equilibrium is point of maximum stability• At equilibrium ΔG = 0, there is no
change in the system• At equilibrium, cells are dead!• Cells must remain at disequilibrium
to continue to work
![Page 17: Metabolism The total of all reactions in a cell. Components of Metabolism Catabolism Breakdown of large molecules into smaller ones Energy is released.](https://reader034.fdocuments.us/reader034/viewer/2022051622/5697c0131a28abf838cccc76/html5/thumbnails/17.jpg)
![Page 18: Metabolism The total of all reactions in a cell. Components of Metabolism Catabolism Breakdown of large molecules into smaller ones Energy is released.](https://reader034.fdocuments.us/reader034/viewer/2022051622/5697c0131a28abf838cccc76/html5/thumbnails/18.jpg)
Exergonic reactions
• Release free energy
• ΔG is negative
• Occur spontaneously
• Can do work
• Respiration is an example
• ΔG for respiration = -686 kcal/mol
![Page 19: Metabolism The total of all reactions in a cell. Components of Metabolism Catabolism Breakdown of large molecules into smaller ones Energy is released.](https://reader034.fdocuments.us/reader034/viewer/2022051622/5697c0131a28abf838cccc76/html5/thumbnails/19.jpg)
Endergonic Reactions
• Absorbs free energy
• ΔG is positive
• Do not occur spontaneously
• Photosynthesis is an example
• ΔG for photosynthesis is 686 kcal/mol
![Page 20: Metabolism The total of all reactions in a cell. Components of Metabolism Catabolism Breakdown of large molecules into smaller ones Energy is released.](https://reader034.fdocuments.us/reader034/viewer/2022051622/5697c0131a28abf838cccc76/html5/thumbnails/20.jpg)
![Page 21: Metabolism The total of all reactions in a cell. Components of Metabolism Catabolism Breakdown of large molecules into smaller ones Energy is released.](https://reader034.fdocuments.us/reader034/viewer/2022051622/5697c0131a28abf838cccc76/html5/thumbnails/21.jpg)
Analyze the ATP Cycle in terms of anabolism, catabolism,
endergoonic, exergonic, and free energy
![Page 22: Metabolism The total of all reactions in a cell. Components of Metabolism Catabolism Breakdown of large molecules into smaller ones Energy is released.](https://reader034.fdocuments.us/reader034/viewer/2022051622/5697c0131a28abf838cccc76/html5/thumbnails/22.jpg)
![Page 23: Metabolism The total of all reactions in a cell. Components of Metabolism Catabolism Breakdown of large molecules into smaller ones Energy is released.](https://reader034.fdocuments.us/reader034/viewer/2022051622/5697c0131a28abf838cccc76/html5/thumbnails/23.jpg)
![Page 24: Metabolism The total of all reactions in a cell. Components of Metabolism Catabolism Breakdown of large molecules into smaller ones Energy is released.](https://reader034.fdocuments.us/reader034/viewer/2022051622/5697c0131a28abf838cccc76/html5/thumbnails/24.jpg)
How does ATP work?
![Page 25: Metabolism The total of all reactions in a cell. Components of Metabolism Catabolism Breakdown of large molecules into smaller ones Energy is released.](https://reader034.fdocuments.us/reader034/viewer/2022051622/5697c0131a28abf838cccc76/html5/thumbnails/25.jpg)