Narcotic drugs are analgesic that exert a depressing action on the central nervous system.
Hope this helps!
Answer:
Walls are thin.
Inner surface is moist.
Tissues are filled with blood vessels.
Exposed to air
Explanation:
Tadpoles have no legs while frogs do.
frogs can go on land while tadpoles can't.
frogs can breathe on land and in water while tadpoles can only breathe in water.
they all evolved from the same species but they had adapted to gather food on their given island. the adaptation was in their beaks
Ok this might not be the best answer but just by reading it, it may be unreliable because numbers do change over time
