2. When bonds break and new bonds form, . - new atoms are created

- electrons are lost

- chemical changes occur

- substances retain their appearance

which is the correct one of these 4

ya the other dude is right

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.