Biological Molecules

Question 1

Atomic number

Answer 1

Number of protons

Question 2

Mass number

Answer 2

Number of protons and neutrons

Question 3

Molecule

Answer 3

Two or more atoms chemically joined together

Question 4

Compound

Answer 4

Two or more atoms of different elements chemically joined together

Question 5

Ion

Answer 5

A charged particle

Question 6

Isotope

Answer 6

Atoms of the same element with different mass numbers

Question 7

pH

Answer 7

The measure of the concentration of Hydrogen Ions present

Question 8

An acid

Answer 8

A substance that dissociates into ions when in a solution, releasing H+.

Question 9

A buffer

Answer 9

Chemicals that act as bases or acids to maintain a stable pH, e.g. plasma proteins

Question 10

Ionic bond

Answer 10

An electrostatic attraction between inorganic compounds, e.g. NaCl

Question 11

Covalent bond

Answer 11

Two hydrogen atoms sharing electrons

Question 12

Specific heat capacity

Answer 12

The amount of energy needed to raise the temperature of a substance, e.g. water

Question 13

Structural Isomers

Answer 13

Two molecules that have the same chemical formula but different structural formulas

Question 14

Condensation reaction

Answer 14

A chemical reaction between two compounds where one of the products is water

Question 15

Hydrolysis reaction

Answer 15

The reaction of water with another (chemical) compound to form two or more products

Question 16

Oxidation reaction

Answer 16

The reaction of oxygen with another (chemical) compound

Question 17

Mucopolysaccharide

Answer 17

Polysaccharides combined with amino acids e.g. chitin

Question 18

Saturated fatty acid

Answer 18

Only contains [C-C] single bonds

Question 19

(Poly)unsaturated fatty acid

Answer 19

Contains one or more [C=C] double bonds

Question 20

Amino acid

Answer 20

An organic compound composed of amine and carboxyl functional groups

Question 21

Amphoteric

Answer 21

Molecules, such as amino acids, which can acts as bases and acids

Question 22

Peptide bond

Answer 22

The chemical bond formed in a condensation reaction between the amine group of one amino acid and the carboxyl group of another.

Question 23

Primary structure

Answer 23

The sequence of amino acids in the chain

Question 24

Secondary structure

Answer 24

The three-dimensional chains of amino acids which form alpha-helixes and beta-sheets, held together by Hydrogen bonds

Question 25

Tertiary structure

Answer 25

The three-dimensional shape that the molecule forms when the polypeptide helix twists and folds around itself

Question 26

Quaternary structure

Answer 26

The linking of a number of polypeptide chains

Question 27

Denaturation

Answer 27

The permanent change of a proteins tertiary and quaternary structure

Question 28

Globular proteins

Answer 28

Compact, highly twisted polypeptide chains rolled up into a ball. Water-soluble, less stable, all enzymes are globular.

Question 29

Prosthetic group

Answer 29

A tightly bound, specific non-polypeptide unit required for the biological function of some proteins

Question 30

Conjugated protein

Answer 30

Combination of a protein with a prosthetic group

Question 31

Fibrous proteins

Answer 31

Polypeptide chains laid down in parallel chains and linked together to form long sheets.

Question 32

Macronutrients

Answer 32

Needed in small amounts in living organisms: the essential elements consumed in the largest quantities e.g. carbon and hydrogen

Question 33

Micronutrients

Answer 33

Needed in minute quantities: trace elements such as salts, ions or elements that support the metabolism e.g. copper