Which of the following mechanisms produces the most ATP during cellular respiration?
Electron transport chain/oxidative phosphorylation
oxidation reactions
substrate-level phosphorylation
lactic acid production
The Correct Answer is A
A. Electron transport chain/oxidative phosphorylation: This stage of cellular respiration produces the majority of ATP, typically about 26–34 molecules per glucose. It relies on the transfer of electrons through protein complexes and the use of a proton gradient to drive ATP synthase activity.
B. oxidation reactions: Oxidation reactions remove electrons from molecules, often transferring them to NAD⁺ or FAD. While essential for energy extraction, these reactions alone do not directly generate large amounts of ATP.
C. substrate-level phosphorylation: This mechanism occurs during glycolysis and the Krebs cycle, producing ATP directly from enzyme-mediated reactions. However, it only accounts for a small fraction of ATP yield, about 2 ATP in glycolysis and 2 in the Krebs cycle.
D. lactic acid production: Lactic acid is formed in anaerobic respiration when pyruvate is reduced to lactate. This process regenerates NAD⁺ for glycolysis but yields no additional ATP beyond the small amount produced in glycolysis itself.
Nursing Test Bank
Naxlex Comprehensive Predictor Exams
Related Questions
Correct Answer is B
Explanation
False:Pyruvic acid is converted into lactic acid only under anaerobic conditions, when oxygen is insufficient for the mitochondria to carry out aerobic respiration. When oxygen is present, pyruvic acid enters the mitochondria and is converted into acetyl CoA, which then enters the Krebs cycle for aerobic respiration. Lactic acid formation does not occur under these oxygen-rich conditions.
Correct Answer is B
Explanation
A. ceruminous:Ceruminous glands are modified sweat glands located in the ear canal that produce earwax (cerumen), not scalp oil.
B. sebaceous:Sebaceous glands are associated with hair follicles and secrete sebum, an oily substance that lubricates the hair and skin, helping to maintain moisture and provide a protective barrier.
C. apocrine sweat:Apocrine sweat glands are found in specific areas such as the axillae and groin. They secrete a thicker, milky sweat, usually in response to stress or hormonal signals, and do not produce scalp oil.
D. mammary:Mammary glands are specialized sweat glands that produce milk. They are not involved in producing scalp oil.
E. merocrine sweat:Merocrine (eccrine) sweat glands are widely distributed and secrete a watery sweat primarily for thermoregulation, not for lubricating hair or skin.
Whether you are a student looking to ace your exams or a practicing nurse seeking to enhance your expertise , our nursing education contents will empower you with the confidence and competence to make a difference in the lives of patients and become a respected leader in the healthcare field.
Visit Naxlex, invest in your future and unlock endless possibilities with our unparalleled nursing education contents today
Report Wrong Answer on the Current Question
Do you disagree with the answer? If yes, what is your expected answer? Explain.
Kindly be descriptive with the issue you are facing.