Carbohydrates
lipids
amino acid
nucleic acid ?
Respiration occurs when glucose<span> (</span>sugar<span> produced during photosynthesis) combines with </span>oxygen<span> to produce useable cellular energy. This energy is used to fuel growth and all of the normal cellular functions. </span>Carbon dioxide<span> and water are formed as </span>by-products<span> of respiration.</span>
Mechanical digestions is usually associated with the mouth. You mechanically chew the food and saliva breaks it down. Chemical digestion occurs in the stomach where stomach acid breaks it down.
Answer:
The spinal cord and the brain
The correct answer would be true. Petroleum and coal are mostly mined from the continental shelf. Most of the oil rigs are found and situated in this area. Gas/oil deposits are found in these areas since the ocean floor is known to exist a 100 million years ago which means deposits and fossil fuels are formed all through out those years.