Iron ions

Question 1

There are actually two versions of iron ions (known as oxidation states)

Answer 1

Iron (II) ions, also known as ferrous ions (Fe2+)

Iron (III) ions, also known as ferric ions (Fe3+)

Question 2

Iron ions are essential as they can bind

Answer 2

oxygen

Question 3

Haemoglobin is the large protein in red blood cells that is responsible for transporting

Answer 3

transporting oxygen around the body

Question 4

Haemoglobin is made up of …. polypeptide chains that each contain one ……………

Answer 4

4

Fe2+

Question 5

Myoglobin in muscles functions in a similar way (it is an ………………) but is only made up of … polypeptide chain (containing one ……………)

Answer 5

oxygen-binding protein

one

Fe2+

Question 6

Iron ions are also essential as they are involved in the transfer of electrons during ………..

Answer 6

respiration and photosynthesis, so they are key to the biological generation of energy

Question 7

Iron ions are an essential component of cytochromes (that are themselves a component of

Answer 7

electron transport chains)

Question 8

Cytochrome c contains an iron ion that is essential to its function

During the electron transport process, this iron ion switches between the ………… states, which allows for electrons to be …………….

Answer 8

Fe3+ and Fe2+ oxidation states

accepted and donated