Beta Oxidation Generates Substrates for Cellular Respiration Through Which of the Following
Beta oxidation generates substrates for cellular respiration through which of the following processes? A) catabolism of glucose B) catabolism of glycogen C) catabolism of proteins D) catabolism of fatty acids
Fatty acids usually have an even number of carbons in their structures. Catabolism of fatty acids produces two-carbon fragments that are converted to acetyl CoA molecules. What is the most likely way in which these acetyl CoA molecules would be metabolised in aerobic cellular respiration? A) They would directly enter the electron transport chain. B) They would directly enter the energy-yielding phase of glycolysis. C) They would be converted to pyruvate and then undergo pyruvate oxidation upon transport into mitochondria. D) They would directly enter the citric acid cycle.
New biosensors, applied like a temporary tattoo to the skin, can alert serious athletes that they are about to "hit the wall" and will find it difficult to continue exercising. These biosensors monitor lactate, a form of lactic acid, released in sweat during strenuous exercise. Which of the statements below is the best explanation of why athletes would need to monitor lactate levels? A) During aerobic respiration, muscle cells cannot produce enough lactate to fuel muscle cell contractions, and muscles begin to cramp, thus athletic performance suffers. B) During anaerobic respiration, lactate levels increase when muscles cells need more energy; however, muscles cells eventually fatigue, thus athletes should modify their activities to increase aerobic respiration. C) During aerobic respiration, muscles cells produce too much lactate, which causes a rise in the pH of the muscle cells, thus athletes must consume increased amounts of sports drinks, high in electrolytes, to buffer the pH. D) During anaerobic respiration, muscle cells receive too little oxygen and begin to convert lactate to pyruvate (pyruvic acid), thus athletes experience cramping and fatigue.
The immediate energy source that drives ATP synthesis by ATP synthase during oxidative phosphorylation is the A) oxidation of glucose and other organic compounds. B) flow of electrons down the electron transport chain. C) H⁺ concentration gradient across the membrane holding ATP synthase. D) transfer of phosphate to ADP.