Which of the following is NOT an excretory product of animals?
Answer Details
Oxygen is not an excretory product of animals. Oxygen is essential for respiration, which is the process that releases energy from food. During respiration, animals take in oxygen and release carbon dioxide as a waste product. Urea is a waste product formed in the liver as a result of protein metabolism, and it is excreted by the kidneys. Sweat is also an excretory product that is produced by sweat glands to regulate body temperature and remove excess water and salts. Therefore, the correct answer is option D, which is oxygen.