Hemoglobin has tetrahedral structure containing four heme groups that surround a globin group.
Heme is ringlike organic compound also known as a porphyrin to which an iron atom is attached. There are four iron atoms that bind four oxygen atoms and transport them to tissues.
It is C beacuse you would produce large quantities of the neurotransmitter to see if it could be used as a potential medication.
Explanation:
Only 10% of calories will be transfered to the next higher level.
5000 * 0.1 = 500.
500 calories will transfer to the secondary consumers.
