Immunoglobulin G: links between chains

The H chains and the L chains are linked by several interchain disulfide bonds. In addition, there are intrachain disulfide bonds that stabilise the folding of each domain formed by the chains.

To appreciate these links, let's first highlight residues.
Each close pair of cysteine residues forms a disulfide bond.

Quiz:

Count the number of disulfide bonds in each part of the molecule and fill in the boxes:

in variable regions of both F_ab there is a total of intra- and interchain links
in constant regions of both F_ab there is a total of intra- and interchain links
in the hinge region there are intra- and interchain links
in the constant region of F_c there are intra- and interchain links

Try to solve the quiz before checking these summaries of all disulfide bonds: