Mixture. a compound is 2 or more elements, so it can't be an element
The answer is the endogenous opiate.
The human body naturally produces its own opiates like substances and uses them as neurotransmitters. These substances include endorphins, enkephalins, and dynorphin, often collectively known as endogenous opioids. Endogenous opioids modulate our reactions to painful stimuli.
Pioneer species are the first organisms to live in an area
Some examples of a pioneer are:
•bunch grass
•milkweed
•queen Anne’s lace
•Sphagnum moss
•sedge
•pitcher plant
It should be 3 or 6... Not 100% sure.
