The first law of thermodynamics says that energy can never be created or destroyed. It can just change forms. According to the second law, this increases the entropy (disorder) of the universe. The Gibbs Free Energy Equation defines the amount of energy in a system that can do work rather than being lost as heat. The change in G (ΔG) over a reaction shows the energy difference between reactants and products. ΔH is the change in enthalpy and ΔS is the change in entropy. Systems want to minimize their free energy. Exergonic reactions are spontaneous and release energy while endergonic reactions require energy to move forward. This energy is exchanged in the form of high-energy bonds in ATP molecules. Reaction-specific enzymes speed up reactions by lowering the activation energy.
triphosphate (ATP) is the energy currency of the cell; it provides
energy for cellular processes.
cellular respiration energy stored in the chemical bonds of organic
compounds is released and used to make ATP. Cellular respiration may
be either aerobic or anaerobic.
glycolysis, a glucose molecule is split into two pyruvate molecules.
This process takes place in the cytoplasm of the cell.
of two ATP and two NADH molecules are produced during glycolysis.
or strict, anaerobes are organisms that can only perform anaerobic
respiration. Facultative anaerobes can perform both aerobic and
cellular respiration is anaerobic, fermentation follows glycolysis
in order to regenerate NAD+ so that glycolysis can continue. In
aerobic respiration, NAD+ is regenerated by the electron transport
types of fermentation are alcohol fermentation and lactic acid
Glycolysis and Anaerobic Respiration
Lecture Slides are screen-captured images of important points in the lecture. Students can download and print out these lecture slide images to do practice problems as well as take notes while watching the lecture.
Notice that the electron carrier NAD+ is reduced to NADH.1215
In the process, glyceraldehyde-3-phosphate is oxidized, and that is going to occur over here as well; so you are going to end up with two NADHs from this step.1221
Now, finally, the energy payoff, energy has been invested. So far, two ATPs were used.1234
In step 7, 1,3-bisphosphoglycerate is converted to 3-phosphoglyceric acid.1242
In that process, it loses a phosphate group, and that phosphate group is transferred to ADP to form ATP.1252
The same thing is happening over here. I have an ATP formed.1262
At this point, we have used two ATPs, and now, two ATPs have been produced; so the energy debt has been paid. We are at 0.1265
In step 8, 2-phosphoglyceric acid or 2-phosphoglycerate is formed from 3-phosphoglyceric acid, and all that involves is movement or transfer of a phosphate group to a different location on this molecule.1275
It does not require the input of energy nor does it produce energy.1294
In step 9, a molecule of water is removed from the substrate, so 2-phosphoglyceric acid is converted to phosphoenolpyruvic acid or more simply PEP.1298
Finally, step 10, we get in the production of another ATP molecule.1312
PEP is converted to pyruvate, and in the process, ADP is phosphorylated.1318
Actually, I want to talk a little bit more about this. ADP is phosphorylated to form ATP.1329
Previously, what we talked about is that ADP and inorganic phosphate, we often talked about forming ATP.1333
That is not what happens here, and I want to talk about the difference.1342
The type of phosphorylation that occurs in glycolysis is called substrate level phosphorylation.1346
Instead of an inorganic phosphate being added to ADP to form ATP, phosphate is transferred from a substrate for example 1,3-bisphosphoglycerate.1359
The phosphate is transferred from there and to the ADP to form ATP, and therefore, it is called substrate level phosphorylation.1371
Both of the phosphorylations in glycolysis occur this way.1383
When we talk about aerobic respiration, a lot of the phosphorylation that we will see occurs by the addition of inorganic phosphate.1388
That is not substrate level phosphorylation, but you should be aware that this is slightly different.1396
The result is the same, though- the production of ATP.1400
The book and CD package include two full length practice exams that are presented with all questions answered and explained. The author also presents detailed reviews of all test topics and includes multiple-choice and free-response questions with answers at the end of each topic's chapter.
This book includes a review of the AP Biology exam format and scoring, proven strategies for answering multiple-choice questions, and hints for tackling the essay questions. The practice tests include answers and explanations and there is also proven test-taking strategies for both the multiple choice and essay parts.