Chapter 2: Chemistry of life

Question 1

The sum of protons and neutrons in the nucleus of an atom.

Answer 1

Mass number

Question 2

One or more electrons transferred fro one atom to the other.

Answer 2

ionic bond

Question 3

When electrons are shared between atoms.

Answer 3

Covalent Bond

Question 4

An uneven distribution of electrons between the atoms.

Answer 4

Polar molecules

Question 5

An attraction between molecules of the same properties.

Answer 5

Cohesion

Question 6

An attraction between molecules of different substances.

Answer 6

Adhesion

Question 7

A material composed composed of two or more elements that are physically mixed but not chemically mixed together.

Answer 7

Mixture

Question 8

Mixture of two or more substances in which the molecules of the substances are evenly distributed.

Answer 8

Solution

Question 9

The substance dissolved in a solution.

Answer 9

solute

Question 10

The substance in which the solute dissolves.

Answer 10

solvent

Question 11

Mixture of water and non-dissolved materials.

Answer 11

suspension

Question 12

Large molecules that in living cells.

Answer 12

Macromolecules

Question 13

Smaller units in macromolecules joined together to make polymers.

Answer 13

Monomer

Question 14

Monomers joined together.

Answer 14

Polymer

Question 15

A compound made up of carbon, hydrogen, and oxygen atoms, usually in a ratio of 1 : 2 : 1. Living things use them as their main source of energy. Plants and some animals also use them for structural purposes.

Answer 15

Carbohydrate

Question 16

Single sugar molecules that include galactose.

Answer 16

Monosaccharide

Question 17

They are the large macromolecules formed from monosaccharides. Many animals store excess sugar in them called glycogen.

Answer 17

Polysaccharide

Question 18

They are made mostly from carbon and hydrogen atoms. The common categories of are fats, oils, and waxes. They can be used to store energy.

Answer 18

Lipid

Question 19

Macromolecules containing hydrogen, oxygen, nitrogen, carbon, and phosphorus. They are polymers assembled from individual monomers known as nucleotides. They store and transmit hereditary, or genetic, information.

Answer 19

Nucleic Acid

Question 20

They consist of three parts: a 5-carbon sugar, a phosphate group, and a nitrogenous base. Individual ones can be joined by covalent bonds to form a polynucleotide, or nucleic acid.

Answer 20

Nucleotide

Question 21

A type of nucleic acid that contains the sugar ribose.

Answer 21

Ribonucleic Acid (RNA)

Question 22

A type of nucleic acid that contains the sugar deoxyribose.

Answer 22

Deoxyribonucleic Acid (DNA)

Question 23

Macromolecules that contain nitrogen as well as carbon, hydrogen, and oxygen. They are polymers of molecules called amino acids. Some control the rate of reaction and regulate cell processes. Some are used to form bones and muscles. Others transport substances into or out of cells or help to fight disease.

Answer 23

Protein

Question 24

Compounds with an amino group; (—NH2) on one end and a carboxyl group (—COOH) on the other end.

Answer 24

Amino Acid

Question 25

A process that changes, or transforms, one set of chemicals into another.

Answer 25

Chemical Reaction

Question 26

The energy that is needed to get a reaction started.

Answer 26

Activation Energy

Question 27

A substance that speeds up the rate of a chemical reaction. They work by lowering a reaction’s activation energy.

Answer 27

Catalyst

Question 28

Proteins that act as biological catalysts. They speed up chemical reactions that take place in cells. They act by lowering the activation energies, which has a dramatic effect on how quickly the reaction is completed.

Answer 28

Enzyme

Question 29

The reactants of enzyme-catalyzed reactions.

Answer 29

Substrate