Chapter 2: The Chemistry of Life

Question 1

Atom

Answer 1

The basic unit of matter

Question 2

Nucleus

Answer 2

Center of an atom

Question 3

Electron

Answer 3

A negatively charged particle

Question 4

Element

Answer 4

A pure substance that is made of only one kind of atom

Question 5

Isotopes

Answer 5

Atoms of the same element that have different numbers of neutrons

Question 6

Compound

Answer 6

A substance formed by the chemical combination of two or more elements in definite proportions

Question 7

Ionic bond

Answer 7

Chemical bond formed when one or more electrons are transferred from one atom to another

Question 8

Covalent bond

Answer 8

Type of bond between atoms in which the electrons are shared

Question 9

Molecule

Answer 9

Smallest unit of most compounds that displays all the properties of that compound

Question 10

Cohesion

Answer 10

The attraction between molecules of the same substance

Question 11

Adhesion

Answer 11

The force of attraction between different kinds of molecules

Question 12

Solution

Answer 12

A type of mixture in which all the components are evenly distributed

Question 13

Suspension

Answer 13

A mixture of water and nondissolved material

Question 14

Acid

Answer 14

A compound that releases hydrogen ions (H+) in a solution; a solution with a pH LESS than 7

Question 15

Base

Answer 15

A compound that releases hydrogen ions (OH-) in a solution ; a solution with a pH MORE than 7

Question 16

Buffer

Answer 16

A compound that prevents sharp, sudden changes in pH

Question 17

Carbohydrate

Answer 17

A compound made of carbon, hydrogen, and oxygen atoms; a type of nutrient that is the main source of energy for the body

Question 18

Lipid

Answer 18

A macromolecule made mostly of carbon and hydrogen atoms; includes fats, oils, and waxes

Question 19

Nucleic acid

Answer 19

A macromolecule containing hydrogen, oxygen, nitrogen, carbon, and phosphorus

Question 20

Protein

Answer 20

A macromolecule that contains carbon, hydrogen, oxygen, and nitrogen; needed by body for growth and repair

Question 21

Amino acid

Answer 21

A compound with an amino group on one end and a carboxyl group on the other

Question 22

Chemical reaction

Answer 22

A process that changes one set of chemicals into another

Question 23

Activation energy

Answer 23

The energy that is needed to get a reaction started

Question 24

Catalyst

Answer 24

Substance that speeds up the rate of a chemical process

Question 25

Enzyme

Answer 25

A protein catalyst that speeds up the rate of specific biological reactions