Choose words of phrases from the list to complete the sentences Each word or phrases may be used once, more than once or not at all

carbon dioxide
nitrogen
anaerobic respiration
amino acids
aerobic respiration
lungs
liver
fats
kidneys
toxic

Excretion is defined as the removal of material and the waste products of metabolism.
Carbon dioxide is formed in humans during the process of .
Urea is produced in the and is excreted in the .
Urea is formed from that the body does not need.​