There are many cases of human disease in which one or another enzyme activity is lacking due to genetic mutation. However, cases in which individuals lack one of the enzymes of the citric acid cycle are extremely rare. Why? Explain thoroughly.

in steps 3 and 5 of the citric acid cycle, the compounds are shortended by one carbon each time. whst is the form of this one-carbon compound? what happens to it in the body?

Why is it reasonable for excess NADH to negatively regulate the citric acid cycle?

a) What carbon-containing molecule exits the citric acid cycle?  Why doesn’t your body capture the carbon-containing molecule you identified in part (a) and use that molecule to build new sugars and fats? Explain your answer.  You have just created a new enzyme that will make the citric acid cycle more efficient! Instead of the citric acid cycle taking 8 steps, all of the bonds between the carbon atoms will be broken in only one step! Is this a good idea? Explain your answer.

There are eight chemical reactions that occur in the citric acid cycle process.  The reactions of the citric acid cycle are shown in the figure below. Several classes of organic reactions like these classes include esterification, decarboxylation, hydration reactions, dehydration of alcohols, oxidation of alcohols, oxidation of aldehydes, reduction of aldehydes, and reduction of ketones.  Find at least one of these reaction classes in the citric acid cycle.  List the reaction number and the reaction. Write a sentence or two on how you were able to make the classification.

One condition is ketoacidosis (low blood pH) which is a potentially life-threatening state, most commonly experienced by diabetics. Ketoacidosis, however, is not typically an issue for healthy people who are following a ketogenic diet. What is the difference between ketoacidosis and ketosis? Why do diabetics sometimes develop ketoacidosis, while healthy people rarely do? Healthy people are well equipped to survive on a ketogenic diet. Why is it important that humans evolved to have the ability to survive without carbohydrate nutrients?

draw by hand the molecules involved in each step of the citric acid cycle. include the enzyme, co enzymes, and other molecules involved as well as energy lost/gained at each step.

In the citric acid cycle, the starting molecule is and the output molecule is

The citric acid cycle is shown. The methyl carbon in acetyl CoA is labeled with C14C14 (shown in red). Identify which of the carbons in each intermediate will be labeled in the first round of the cycle by selecting the indicated carbon(s). Each question has multiple options, answering with only one option is incorrect.  Which carbon(s) in α‑ketoglutarate will contain C14? 1 2 3 4 5 Which carbon(s) in succinyl‑CoA will contain C14? 1 2 3 4 Which carbon(s) in succinate will contain C14? 1 2 3 4 Which carbon(s) in fumarate will contain C14? 1 2 3 4 Which carbon(s) in malate will contain C14? 1 2 3 4 Which carbon(s) in oxaloacetate will contain C14? 1 2 3 4

For a lot of enzymes that work on fatty acids, the rate determining step is the release of the product from the active site. This means that the activation energy for product release is much higher than the free energy of catalysis. What enthalpic or entropic contributions would make the activation energy for product release so high and explain?