2A - Protein Structure And Function

Question 1

protein

Answer 1

A biomacromolecule made of an amino acid chain folded into a 3D shape.

Question 2

polypeptide

Answer 2

A long chain of amino acids. Proteins can be made of one or many polypeptides.

Question 3

proteome

Answer 3

All the proteins that are expressed by a cell or organism at a given time.

Question 4

enzyme

Answer 4

An organic molecule, typically a protein, that catalysis (speeds up) specific reactions.

Question 5

peptide hormone

Answer 5

A protein signalling molecule that regulates physiology or behaviour.

Question 6

antibody

Answer 6

A protein produced by plasma cells during the adaptive immune response that is specific to an antigen and combats pathogens in a variety of ways. Also known as immunoglobulin.

Question 7

carboxyl group

Answer 7

The functional group on amino acid molecules that contains a hydroxyl group (OH) and an oxygen double-bonded to a carbon.

Question 8

amino group

Answer 8

The functional group on amino acid molecules that is made of one nitrogen and two hydrogens (NH2)

Question 9

R-group

Answer 9

The variable portion of an amino acid molecule. It can be one of twenty variations and determines the identity of the amino acid.

Question 10

hydrophobic/non polar

Answer 10

Having a tendency to repel and be insoluble in water.

Question 11

hydrophilic/polar

Answer 11

Having a tendency to be attracted to and dissolve in water.

Question 12

monomer

Answer 12

A molecule that is the smallest building block of polymer.

Question 13

polymer

Answer 13

A large molecule that is made of small, repeated monomer subunits.

Question 14

condensation reaction

Answer 14

A reaction where two monomers join to form a larger molecule, producing water as a by-product.

Question 15

peptide bond

Answer 15

The chemical bond linking two amino acids.

Question 16

primary structure

Answer 16

The first level of protein structure, which refers to the sequence of amino acids in polypeptide chain.

Question 17

secondary structure

Answer 17

The level of protein structure where the amino acid chain forms either alpha-helices, beta-pleated sheets, or random coils.

Question 18

tertiary structure

Answer 18

The functional 3D shape of a polypeptide chain.

Question 19

quaternary structure

Answer 19

The level of protein structure where multiple polypeptide chains bond together, or other non-protein groups are added to form a fully functional protein.

Question 20

alpha helix

Answer 20

An organised coiled secondary structure of proteins.

Question 21

beta-pleated sheet

Answer 21

An organised folded secondary structure of proteins

Question 22

random coil

Answer 22

An irregular secondary structure of proteins that is neither an alpha helix nor a beta-pleated sheet.

Question 23

disulphide bond

Answer 23

A strong covalent bond occurring between two sulphur atoms.

Question 24

prosthetic group

Answer 24

A non-protein group bound to a protein. Eg. a vitamin or ion.

Question 25

biomacromolecule

Answer 25

A large organic molecule, found in organisms. Comprised of smaller subunits.