Derived from glucose is the starting material of

which undergoes an

reaction that is mediated by the enzyme,

This forms the intermediate, 6-Phosphoglucono-?-lactose and also generates

The intermediate then undergoes a

reaction, forming H+ and 6-Phosphogluconate. This undergoes

and forms the 5 carbon sugar

and

and CO2

Ribulose-5-phosphate is interconversed via isomerisation to

and epimerised to

The two C5 molecules reacts with one another to produce the C3 molecule of

and a C7 molecule. C3 and C7 molecules reacts with one another to form the C6 molecule,

and a C4 molecule. The C4 molecule and C5 molecule,

Reacts to reproduce the C3 molecule

, and another one of the C6 molecule,

pentose to

Hexoses and

Triose

Red blood cells have no nucleus or organelles and obtain energy from

Red blood cells contains haemaglobin. It's haem component contain iron. Oxygen binds onto the when it is in its

(ferrous) state. Sometimes it can react with oxygen and form

(ferric). In this state, oxygen is unable to bind and haemaglobin becomes

(Hi). If water is added, it makes it irreversible. A reactive oxygen species (ROS),

is also formed which can damage the cell.