What is important about the minerals calcium and iron?

Calcium builds bones and teeth; activates enzymes throughout the body. It helps regulate blood pressure; and helps muscles to contract, nerves to send messages, and blood to clot and Iron helps make hemoglobin which is the oxygen-carrying chemical in the body's red blood cells, and myoglobin which is a protein in muscle cells. Iron is essential for activating certain enzymes and for making amino acids, collagen, neurotransmitters, and hormones..