3.1.8 Ionorganic Ions

Question 1

Role of hydrogen ions

Answer 1

Control the pH of a substance. Enzyme controlled reactions affected by pH

Question 2

Role or iron ions in haemoglobin

Answer 2

Haemoglobin is a large protein that carries oxygen around the body in red blood cells.
Made from 4 polypeptide chains with Fe2+ in centre. The Fe2+ binds to the oxygen in the haemoglobin. When oxygen is bound the Fe2+ temporarily becomes a Fe3+ ion until oxygen is released

Question 3

Role of sodium ions

Answer 3

Co transport of glucose and amino acids.

Molecule or glucose or amino acid can be transported into a cell alongside sodium ions

Question 4

Role of phosphate ions

Answer 4

When PO4^3- is attached to another molecule, it’s know as phosphate group
It’s in DNA, RNA, ATP
Bonds between phosphate groups store energy in ATP
Phosphate groups in DNA and RNA allow nucleotides to join up and form polynucleotides