Lesson Topic 1.2: Basic Chemistry related to the Human Body

Question 1

chemical

Answer 1

fundamental unit in chemistry

Question 2

elements total

Answer 2

112

118 in book

Question 3

elements present in human body

Answer 3

26

Question 4

4 major elements 96%

Answer 4

oxygen
hydrogen
carbon
nitrogen

Question 5

atom

Answer 5

smallest unit of an element

Question 6

atom contain

Answer 6

Nucleus that has protons (+), neutrons (0)
Electrons (–) surrounding nucleus

Total charge is neutral:
Protons # = electron #

Question 7

Atomic number

Answer 7

equals the number of protons that also equals the number of electrons

Question 8

atomic mass number

Answer 8

equals the number of protons and number of neutrons

Question 9

Ion

Answer 9

When an atom that has a positive or negative charge bc it has unequal numbers of protons and electrons

Question 10

molecule

Answer 10

atoms share electrons

Question 11

compound

Answer 11

2 or more different atoms held together with chemical bonds

Question 12

Types of chemical bonds

Answer 12

Ionic
Covalent
Hydrogen

Question 13

Chemical reaction

Answer 13

Occur when old bonds break and new bonds form

Question 14

Chemical reaction types

Answer 14

Synthesis
Decomposition
Exchange
Reversible

Question 15

snythesis

Answer 15

2 or more atoms, joins, or molecules combine to firm new and larger molecules

Question 16

decomposition

Answer 16

split up large molecules into smaller atoms, ions, or molecules

Question 17

exchange

Answer 17

in the body.
consist of both synthesis and decompostion

Question 18

reversible

Answer 18

the products can revert by two half-arrows pointing in oppostite directions

Question 19

inorganic compounds

Answer 19

Structure: lack C-H bonds; structurally simple
Examples
Water, carbon dioxide, bicarbonate, acids, bases, and salts

WATER
Most abundant chemical in human body
Good solvent and lubricant
Takes part in chemical reactions
Absorbs and releases heat slowly; regulates body temperature
Involved in digestion, circulation, and elimination of wastes

Question 20

Organic Compounds

Answer 20

Structure:
All contain C-H bonds
Structurally complex (include polymers composed of many units = monomers)
Classes: carbohydrates, lipids, proteins, nucleic acids

Question 21

pH Concept

Answer 21

The concentration of H+ or OH– expressed on the pH scale

pH scale: 0–14

pH 7.0: H+ concentration = OH– concentration

pH < 7.0 = more H+ (acid)
The smaller the number, the more H+

pH > 7.0 = more OH– (alkaline)
The larger the number, the more OH–

Question 22

more PH Concept

Answer 22

pH 7.0: H+ concentration = OH– concentration
pH < 7.0 = more H+ (acid)

The smaller the number, the more H+

pH > 7.0 = more OH– (alkaline)
The larger the number, the more OH–

Question 23

Buffering System-

Answer 23

Even though strong acids and bases may be taken into the body or be formed by body cells, the pH of fluids inside and outside cells remains almost constant.

Question 24

Buffers

Answer 24

Chemical compounds that act quickly to temporarily bind H+, removing the highly reactive, excess H+ from solution but not from the body.