Answer:
They are called Trace elements
they function as catalysts for enzymatic reactions
in some oxidation-reduction reactions (Cu) for some metabolic reactions to for ATPs synthesis,and
also as oxygen carrying elements in Hb and myoglobin muscles e,g(Fe)
Step-by-step explanation:
Basically Trace elements are group of minerals in small quantity in living organisms.Their functions may be important or essential to the organisms,or needed in small amounts non essentials.
Example of these elements are Fe,Zn,Se,Cu,I,Mn Mb. etc
They are also involved in prevention of some diseases .Generally when they are consumed in large amounts they are toxic to living cells.
others like aluminum, cadmium, mercury lead may beneficial to living organisms,but there role has not yet be verified.