Chapter 3 questions
How many ATP are produced in total from the aerobic breakdown of 1 glucose molecule? (Remember that 1 glucose molecule produces 2 pyruvate molecules, and each pyruvate molecule will go through 1 turn of the citric acid cycle.)
. 32- A total of 32 ATP are produced from the aerobic breakdown of 1 glucose molecule. 2 ATP and 2 NADH are produced via glycolysis (when oxygen is available), 2 NADH are produced when pyruvate converts to acetyl CoA, and 2 GTP, 6 NADH, and 2 FADH are produced via the citric acid cycle (with each NADH molecule leading to the production of 2.5 ATP, and each FADH molecule leading to the production of 1.5 ATP). See Table 3.2 for further details.
What is the organelle that is involved in the oxidative conversion of nutrients into usable cellular energy?
. mitochondrion- The mitochondrion is where the citric acid cycle, electron transport chain, and beta oxidation take place.
How many ATP are required in the energy-investment phase of glycolysis when glucose is being broken down?
2 Two ATP are required to prime glycolysis. Both glucose and fructose-6-phosphate are phosphorylated (have a phosphate added) by ATP. Though 4 ATP are produced overall for every 1 glucose that enters glycolysis, there is a net yield of 2 ATP once you consider that 2 ATP are needed to be added at the start to prime the process of glycolysis. When glycolysis begins with glycogen, only fructose-6-phosphate needs to be phosphorylated by ATP, so only 1 ATP is required and the net ATP yield is 3 ATP in this case. See figures 3.13, 3.14, and 3.15 for further details.
What is produced overall with each turn of the citric acid cycle?
3 NADH, 1 FADH, and 1 GTP For each Acetyl CoA molecule that enters the citric acid cycle, there are 3 NADH, 1 FADH, and 1 GTP (equivalent to 1 ATP) produced. See figure 3.18 for further details.
What molecule enters the citric acid cycle?
Acetyl CoA Acetyl CoA enters the citric acid cycle and can be formed by the breakdown of glucose, fats, or proteins.
Beta oxidation is the breakdown of free fatty acids. What is the end product of beta oxidation?
Acetyl CoA Acetyl CoA is the end product of beta oxidation, which then enters the citric acid cycle.
What is the chemical process of converting nutrients into a biologically usable form of energ
Bioenergetics - is the process of converting nutrients, such as carbohydrates, fats, and proteins, into a biologically usable form of energy.
The breakdown of glucose to pyruvate is a process called:
Glycolysis Glycolysis is the breakdown of glucose to pyruvate. Glycolysis is considered an anaerobic process when no or limited oxygen is available. Glycolysis can also be considered to be the first step in the aerobic production of ATP when oxygen is present because pyruvate can enter the citric acid cycle where the aerobic processes to produce ATP are continued.
What happens at the end of glycolysis when there is no or limited oxygen available?
Lactate is formed When there is no or limited oxygen available, pyruvate converts to lactate. The NADH that is produced from glycolysis stays in the cytoplasm instead of being shuttled into the mitochondria, and donates the H+ to pyruvate so the pyruvate converts to lactate (catalyzed by the enzyme lactate dehydrogenase). See figure 3.16 and 'A Closer Look' 3.3 for further details.
Which energy system is the simplest and most rapid method of producing ATP in the cell?
The breakdown of lactate The breakdown of phosphocreatine involves one reaction and releases enough energy to resynthesize ATP, making the system the fastest and simplest method of producing ATP.