Oxygen is used up in the body of most organisms and Carbon dioxide is released. The body uses oxygen to break down glucose to supply energy tot he body. In result of this reaction carbon dioxide and water is released into the system along with energy. The carbon dioxide is then exhaled into the air by the respiratory system of the organisms.
Answer:
The three sections of the small intestine are the duodenum,
Explanation:
The duodenum
It receives chyme from the stomachs
Its intestinal cells enzymes such as secrete amylase, sucrase, and lipase enzymes that break down fats and sugars.
The jejunum
It is covered in villi and microvilli giving the name THE PRINCIPAL SITE of digestion.
the ileum.
Aid absorption e.g. amino acids, lipids, fat-soluble vitamins, and vitamin B12.
Chemotrophs (Bacteria) are essential in the conversion of nitrogen containing compounds to nitrogen forms that are accessible and usable by plants.