Proteins Structure (Page 2 of 2) in pdf

Proteins Structure Page 2

C h e m g u id e – q u e s t i o n s

c) The diagram (modified from the Chemguide page) shows a close-up view of one of these

ribbons. Mark the intermolecular forces on the diagram.

This diagram (also modified from the Chemguide page)

shows some of the bits of the protein chain in the spirals.

d) What name is given to the spirals?

e) Name the intermolecular forces holding the spiral

together and mark them on the diagram.

f) What is represented by the string-like sections of the

protein?

g) Proteins are described in terms of their primary,

secondary and tertiary structures (and quaternary, but we

aren’t concerned with that at this level). What level of structure are we talking about in the

diagrams above?

3. The overall shape of a protein, the tertiary structure (if you said that in the last question, you were

wrong!), is controlled by ionic interactions, hydrogen bonds, van der Waals dispersion forces and

sulphur-sulphur bridges between the chains. Explain how each of these arises. (Be as precise as

you can, but you are not expected to be able to name specific amino acids, or know the structures of

specific side-groups.)

Proteins Structure Page 2