Statistics for CCEA Biologically Important Ions

Click here to take the quiz!

Ion	Biological Roles	% Correct
Phosphate (PO₄³⁻)	As phospholipids in cell membranes	50%
	Component of adenosine triphosphate (ATP)	50%
	Component of chlorophyll	50%
	Component of nucleic acids	50%
	Component of nucleic acids	50%
Calcium (Ca²⁺)	Essential component of middle lamella (calcium pectate)	50%
Magnesium (Mg²⁺)	Essential in giving chlorophyll its light-absorbing properties	50%
Hydrogencarbonate (HCO₃⁻)	Important as a natural buffer	50%
Iron (Fe²⁺)	Part of haem group in haemoglobin	50%
Nitrate (NO₃⁻)	Component of amino acids	0%
	Essential component of bones and teeth in animals	0%
	Essential in blood clotting	0%
	Important constituent of electron carriers in respiration	0%
Potassium (K⁺)	Important in maintaining electrical gradients across neurones	0%