Compare coenzymes with substrates. how do they work together in enzyme catalysis

air enters through the nose, moves through the nasal cavity, the pharynx, the larynx, enters the trachea, moves through the bronchi andbronchioles till the alveoli.

these muscles maintain the blood pressure in the vessels. the smooth muscles are innervated by nerves of the autonomic nervous system. when the muscles contract, they cause vasoconstriction of the vessels and increase blood pressure. when the muscles relax, they enable vasodilation of the   blood vessels hence reduce blood pressure.