BCH4024 11724 OC F24 E3 Q1: You see a patient in your clinic who complains that they are unable to carry out long, intensive exercise. You have a muscle biopsy performed, and the results indicate a deficiency in the enzyme that catalyzes the following reaction. What is the enzyme, and why does a deficiency of this enzyme lead to rapid muscle fatigue?

BCH4024 11724 OC F24 E3 Q6: (the first part is the same as the last question) A child presents with severe neurological defects.  Blood tests indicate elevated serum levels of lactate, pyruvate, and alanine. Cultures of skin fibroblasts showed deficient activity of the pyruvate dehydrogenase (PDH) complex. Suppose the specific defect was a mutant E1 catalytic subunit of the PDH complex with poor binding of its prosthetic group/coenzyme. Increasing the dietary precursor of such coenzyme can be helpful in treating the patient. In this case, which of the following may be helpful?

BCH4024 11724 OC F24 E3 Q5: A child presents with severe neurological defects.  Blood tests indicate elevated serum levels of lactate, pyruvate, and alanine. Cultures of skin fibroblasts showed deficient activity of the pyruvate dehydrogenase (PDH) complex. Which of the following conditions can inhibit PDH activity? High [ATP] High [CoA-SH] High [Acetyl CoA] High NADH

BCH4024 11724 OC F24 E3 Q9: A 3-day-old male infant has poor feeding, decreased muscle tone, and several seizures per day. Lab tests show elevated levels of lactate, massive elevations of fumarate, and decreased levels of malate. You suspect a problem with the citric acid cycle and think he most likely has a deficiency of ____________.

BCH4024 11724 OC F24 E3 Q19: Mitchell’s chemiosmotic theory suggested that a high concentration of protons outside the mitochondrial membrane ______________.

BCH4024 11724 OC F24 E3 Q28: Refer to the pathway drawn below. The letters in brackets [ ] represent additional substrates and products for the reactions indicated. Which of the following statements regarding the production of molecule B in the above pathway is TRUE?

BCH4024 11724 OC F24 E3 Q36: The next two questions deal with the following case: A three-year-old boy is brought into the clinic suffering from cardiorespiratory distress following an infection. Previously the boy was admitted to the hospital in a coma and suffered a cardiac arrest. He was extremely hypoglycemic (plasma glucose = 15 mg/dl) and showed hepatomegaly (enlarged liver). Muscle and liver biopsies contain large amounts of lipids.  The diagnosis was a carnitine deficiency. Loss of carnitine will most directly affect which of the following processes?

ADH targets which region of the renal tubule?

In response to a drop in overall blood pressure,__________ stimulates constriction of the glomerular inlet and even greater constriction of the outlet.

Through which of these structures does urine travel?