B2.1- Proteins

Which group is NOT attached to the alpha carbon atom in an amino acid?

• Carboxyl group

• Amine group

• R-group

• Phosphate group

What type of reaction results in the formation of dipeptides and longer chains of amino acids?

• Condensation reaction

• Hydrolysis reaction

• Redox reaction

• Ionic reaction

Which type of amino acids cannot be synthesized and must be obtained from food?

• Non-essential amino acids

• Essential amino acids

• Polar amino acids

• Non-polar amino acids

What determines the properties of assembled polypeptides?

• The sequence of amino acids

• The number of amino acids

• The R-groups

• Both A and C

What determines the three-dimensional shape of proteins?

• The sequence of amino acids and the precise position of each amino acid within a structure

• The type of bonds between amino acids

• The number of amino acids

• The type of R-group

What stabilizes alpha helices and beta-pleated sheets in the secondary structure of proteins?

• Ionic bonds

• Hydrogen bonds

• Disulfide covalent bonds

• Hydrophobic interactions

What type of bonds does NOT depend on the tertiary structure of proteins?

• Hydrogen bonds

• Ionic bonds

• Disulfide covalent bonds

• Peptide bonds

What type of amino acids are found in the core of globular proteins that are soluble in water?

• Polar

• Non-polar

• Essential

• Non-essential

What is an example of a conjugated protein?

• Insulin

• Collagen

• Haemoglobin

• All of the above

What technology has allowed imaging of single-protein molecules and their interactions with other molecules?

• Cryogenic electron microscopy

• Atomic force microscopy

• Scanning tunneling microscopy

• X-ray crystallography