Chapter 2 The Chemical Level of Organization

Question 1

What is chemistry?

Answer 1

the science that investigates matter and its interact

Question 2

What is matter?

Answer 2

Anything that takes up space and has mass

Question 3

What is atomic number?

Answer 3

the number of protons in an atom

Question 4

Mass number

Answer 4

total number of protons and neutrons in the nucleus

Question 5

Atoms are electrically neutral, meaning:

Answer 5

every positively charged proton is balanced by a negatively charged electron

Question 6

What determines the chemical properties of an element?

Answer 6

The number of electron’s in the atom’s outer shell

Question 7

Chemical bonding produces ____ and ____.

Answer 7

molecules and compounds

Question 8

Molecules are:

Answer 8

chemical structures that contain more than one atom bonded together by shared electrons

Question 9

A compound is:

Answer 9

any chemical substance made up of atoms of two or more elements

Question 10

What are surfactants?

Answer 10

Chemicals that act as wetting agents

Question 11

Why do premature babies often suffer from pulmonary disease?

Answer 11

Because surfactant is not produced by the fetus until approximately 28-32 weeks of gestation

Question 12

What is energy?

Answer 12

the capacity to perform work

Question 13

What is work?

Answer 13

the movement or change in the physical structure of matter

Question 14

What is kinetic energy?

Answer 14

the energy of motion

Question 15

What is potential energy?

Answer 15

stored energy

Question 16

What is a decomposition reaction?

Answer 16

breaks a molecule into smaller fragments

Question 17

Hydrolysis

Answer 17

one of the bonds in a complex molecule is broken, and the components of a water molecule are added to the resulting fragments

Question 18

What is dehydration synthesis?

Answer 18

condensation; the formation of a complex molecule by the removal of water

Question 19

What is anabolism?

Answer 19

the synthesis of new compounds in the body

Question 20

What is an exergonic reaction?

Answer 20

a reaction that releases energy

Question 21

What is an endergonic reaction?

Answer 21

A reaction that absorbs energy

Question 22

What are nutrients?

Answer 22

The essential elements and molecules that are obtained from the diet

Question 23

What is an acid?

Answer 23

any substance that breaks apart in solution to release hydrogen ions

Question 24

What is a base?

Answer 24

a substance that removes hydrogen ions from a solution

Question 25

How is the concentration of hydrogen ions reported?

Answer 25

as the pH

Question 26

Pure water has a pH of ___

Answer 26

7

Question 27

A solution with a pH of 7 is called ____ because:

Answer 27

neutral; it contains equal numbers of hydrogen ions and hydroxide ions

Question 28

A solution with a pH below 7 is:

Answer 28

acidic

Question 29

A solution with a pH above 7 is:

Answer 29

basic or alkaline

Question 30

The pH of blood and most body fluids normally ranges from ____ to ____

Answer 30

7.35 to 7.45

Question 31

A blood pH below 7 can produce:

Answer 31

coma

Question 32

A blood pH above 7.8 usually causes:

Answer 32

uncontrollable, sustained muscular contractions

Question 33

What are buffers?

Answer 33

compounds that stabilize pH by either removing or replacing hydrogen ions

Question 34

pH is an abbreviation of:

Answer 34

potential of hydrogen

Question 35

How is the value of 7.0 derived as the pH of a precisely neutral solution?

Answer 35

it is the absolute value of the hydrogen ion concentration at 25°C

Question 36

A pH of 14 indicates that:

Answer 36

only hydroxide ions are present

Question 37

A pH of 0 indicates that:

Answer 37

only hydrogen ions are present

Question 38

What is pOH?

Answer 38

denotes the alkalinity of a solution; represents the number of hydroxide ions present

Question 39

pH + pOH = ____

Answer 39

14

Question 40

Organic compounds always contain:

Answer 40

carbon and hydrogen and generally water as well

Question 41

What is a carbohydrate?

Answer 41

an organic molecule that contains carbon, hydrogen, and oxygen in a ratio near 1:2:1

Question 42

What is a monosaccharide?

Answer 42

a simple sugar; a carbohydrate that contains from 3 to 7 carbon atoms

Question 43

What is the most important metabolic "fuel" in the body?

Answer 43

glucose

Question 44

Two monosaccharides joined together form a ______

Answer 44

disaccharide

Question 45

What is a disaccharide?

Answer 45

two monosaccharides joined together; i.e. sucrose (table sugar)

Question 46

What is a salt?

Answer 46

an ionic compound that consists of any cation except a hydrogen ion and any anion except a hydroxide ion

Question 47

What is an ion?

Answer 47

an atom or molecule with an electric charge

Question 48

What are cations?

Answer 48

Ions with a positive charge

Question 49

What are anions?

Answer 49

Ions with a negative charge

Question 50

What is an ionic bond?

Answer 50

a chemical bond created by the electrical attraction between anions and cations

Question 51

What is covalent bonding?

Answer 51

a bond in which atoms share electrons with other atoms

Question 52

Activation energy

Answer 52

the amount of energy required to start a reaction

Question 53

Enzymes

Answer 53

belong to a class of substances called catalysts, which are compounds that accelerate chemical reactions without themselves being permanently changed

Question 54

Inorganic compounds are small molecules that do not contain ____ and ____ atoms.

Answer 54

carbon and hydrogen

Question 55

What are electrolytes?

Answer 55

Inorganic compounds whose ions can conduct an electrical current in solution

Question 56

What are steroids?

Answer 56

Large lipid molecules composed of four connected rings of carbon atoms

Question 57

Phospholipids

Answer 57

consist of a glycerol and two fatty acids linked to a nonlipid group by a phosphate group

Question 58

What are the 7 functions of protein?

Answer 58

1. support 2. movement 3. transport 4. buffering 5. metabolic regulation 6. coordination, communication, and control 7. defense

Question 59

What are proteins?

Answer 59

long chains of organic molecules called amino acids

Question 60

What determines the functional properties of a protein?

Answer 60

it's shape

Question 61

What are the reactants in an enzymatic reaction?

Answer 61

substrates

Question 62

What are nucleic acids?

Answer 62

Large organic molecules composed of carbon, hydrogen, oxygen, nitrogen, and phosphorus. They store and process information at the molecular level inside cells

Question 63

What are the five nitrogenous bases in a nucleotide?

Answer 63

adenine, guanine, cytosine, thymine, and uracil

Question 64

The energy that powers a cell is obtained by:

Answer 64

the breakdown (catabolism) of organic molecules such as glucose

Question 65

ATP is composed of:

Answer 65

adenosine monophosphate and two phosphate groups