Question

in humans, what is a by-product of anaerobic respiration or fermentation? 18 ethanol oxygen lactic acid glucose

Explanation:

In human anaerobic respiration (fermentation), glucose is broken down without oxygen. The process produces lactic acid as a by - product. Ethanol is a product of anaerobic respiration in yeast, oxygen is used in aerobic respiration, and glucose is the reactant for respiration.

Answer:

lactic acid