Chapter 2 : The Chemical Basis of Life

Question 1

Chemical

Answer 1

Any substance used in or resulting from a reaction involving changes to atoms or molecules and are found in our bodies, the bodies of other organisms, and the physical environment

Question 2

Matter

Answer 2

Anything that occupies space and has mass

Question 3

Element

Answer 3

A substance that cannot be broken down to smaller substances while still maintaining its unique properties

Question 4

The 4 most abundant elements in living organisms (96.3%)

Answer 4

C
H
N
O

Question 5

The other elements that take up 3.7% of the body

Answer 5

Ca
P
K
S 
Na
Cl
Mg

Question 6

Trace elements

Answer 6

Essential but only needed in minute quantities (0.01%)

Question 7

Trace element examples

Answer 7

Iron (anemia)
Iodine (goiter)
Fluoride (tooth decay)

Question 8

Atom

Answer 8

The smallest unit of matter that still retains the properties of an element

Question 9

Proton

Answer 9

Positively charged subatomic particle

Question 10

Electron

Answer 10

Negatively charged subatomic particle

Question 11

Neutron

Answer 11

Electrically neutral subatomic particle

Question 12

Mass number

Answer 12

The sum of the number of protons and neutrons in the nucleus and is measured in daltons

Question 13

Isotope

Answer 13

Each of two or more forms of the same element that contain equal numbers of protons but different numbers of neutrons in their nuclei

Question 14

Radioactive isotope

Answer 14

An atom in which the nucleus decays spontaneously giving off particles or energy

Question 15

Compound

Answer 15

A substance consisting of 2 or more different elements chemically bound in a fixed ratio