What toxic waste product is produced by anaerobic lactic metabolism?

Lactic acid, also known as lactate, is the toxic waste product produced during anaerobic lactic metabolism. This process occurs when the body requires energy but oxygen is limited, such as during intense exercise. In the absence of sufficient oxygen, glucose is broken down into lactic acid instead of being fully oxidized to carbon dioxide and water. Accumulation of lactic acid can lead to muscle fatigue and discomfort, which are common during high-intensity activities.

The other options represent different metabolic byproducts: carbon dioxide is produced during aerobic metabolism, while ammonia and urea are associated with protein metabolism and the breakdown of amino acids. In the context of anaerobic metabolism specifically, lactic acid is the primary toxic waste that arises when energy demands exceed the oxygen available for aerobic cellular respiration.