31.   One targets a crucial type of protein molecule found on the head of sperm.

32.   Protein molecules have three-dimensional shapes that have to fold in precise ways for the cells to function.

33.   Protein molecules perform most essential functions in our bodies.

34.   Prions seem to be protein molecules that have somehow become badly formed and that have the ability to turn other proteins bad.

35.   Receptors are protein molecules that carry out various functions in cells and can sometimes be exploited by viruses or bacteria seeking to attack the cells.

36.   Protein molecules in their myriad varieties form the basic constituent of all living matter, from bacteria to plants to higher animals.

37.   The abberant protein molecules are folded abnormally and it is this feature that seems to endow them with their ability to cause disease.

38.   The equipment on hand was barely adequate, but persistence prevailed when he and a colleague, Max Perutz, identified the properties of globular protein molecules.

39.   The gene carries the code for a type of protein molecule known as a transcription factor.