They breathe through their skin. Air dissolves on the mucus of their skin, so they MUST stay moist to breathe. If worms dry out, they suffocate. As fresh air is taken in through the skin, oxygen is drawn into the worm's circulatory system, and the worm's hearts pump the oxygenated blood to the head area.
Answer:
Invertebrates are the organisms in which backbone or vertebral column is absent.
The three macroinvertebrate categories are annelids, mollusks and arthropods.
Annelids are the organisms having segmented body. They are found in moist places. Examples are leeches and earth worms.
Mollusks are the organisms which are enclosed in a calcium carbonate shell. Examples are snails and slugs.
arthropods are the invertebrates which have segmented body and jointed appendages. Examples are insects and crustaceans etc.
During the last and final stage where there is a possibility of 30-36 ATP production rate
It is A both chemical changes and flow of energy
