Deck 2: Introductory Chemistry

Question 1

In an average lean healthy adult, 55% to 60% of the body weight is composed of

A)amino acids
B)salts
C)water
D)fat
E)proteins

Answer 1

C

Question 2

Substances that cannot be broken down into simpler substances by ordinary chemical means are called

A)matter
B)compounds
C)chemical elements
D)inorganic molecules
E)organic molecules

Answer 2

C

Question 3

All of the following are organic compounds EXCEPT

A)nucleic acids
B)water
C)proteins
D)lipids
E)carbohydrates

Answer 3

B

Question 4

Which of the following is an abundant element found in both water molecules and most organic molecules?

A)nitrogen
B)hydrogen
C)potassium
D)carbon
E)sodium

Question 5

When two or more atoms share electrons, the resulting combination is called a/an

A)electrolyte
B)ion
C)element
D)molecule
E)salt

Question 6

The chemical symbol for sodium is

A)N
B)S
C)Mg
D)Na
E)Sn

Question 7

An atom that has given up or gained an electron is referred to as a/an

A)molecule
B)neutron
C)ion
D)compound
E)isotope

Question 8

A chemical bond formed between two oppositely charged ions is a/an

A)hydrogen bond
B)ionic bond
C)single covalent bond
D)double covalent bond
E)polar covalent bond

Question 9

The most common type of chemical bond in the human body is the

A)covalent bond
B)ionic bond
C)hydrogen bond
D)double bond
E)none of the choices is correct

Question 10

The normal pH of blood is

A)4.00 to 5.00
B)6.75 to 7.00
C)7.20 to 7.60
D)7.35 to 7.45
E)7.65 to 8.00

Question 11

A molecule that dissociates into one or more hydrogen ions when dissolved in water is a/an

A)salt
B)acid
C)base
D)buffer
E)solvent

Question 12

Most of the energy needed to drive energy-requiring chemical reactions in the body is provided by the hydrolysis of

A)ribonucleic acid (RNA)
B)deoxyribonucleic acid (DNA)
C)adenosine diphosphate (ADP)
D)adenosine triphosphate (ATP)
E)adenosine monophosphate (AMP)

Question 13

An atom that gives up electrons becomes a/an

A)anion
B)cation
C)compound
D)electron
E)molecule

Question 14

All of the following are properties of water EXCEPT

A)water is an excellent solvent.
B)water absorbs heat very quickly.
C)water participates in many chemical reactions.
D)water serves as a lubricant.
E)water releases heat very slowly.

Question 15

A chemical bond in which one pair of electrons is shared between two atoms is a/an

A)hydrogen bond
B)ionic bond
C)single covalent bond
D)double covalent bond
E)triple covalent bond

Question 16

The backbone and rings of all organic molecules are formed by

A)carbon
B)oxygen
C)magnesium
D)phosphorus
E)nitrogen

Question 17

Negatively charged particles in an atom are called

A)neutrons
B)electrons
C)protons
D)elements
E)isotopes

Question 18

Which of the following describes the most acidic solution?

A)pH 4
B)pH 5
C)pH 7
D)pH 9
E)pH 14

Question 19

The number of protons in the nucleus of an atom is indicated by the

A)atomic mass
B)atomic number
C)molecular formula
D)atomic weight
E)valence number

Question 20

A type of weak chemical bond that forms between a hydrogen atom with partial positive charge and another atom with partial negative charge is called a/an

A)hydrogen bond
B)ionic bond
C)single covalent bond
D)double covalent bond
E)none of the choices is correct

Question 21

Which of the following best describes how energy is released from ATP stored in cells?

A)The terminal phosphate is hydrolyzed.
B)All three phosphates are sequentially removed by dehydration reactions.
C)The adenosine is reduced to adenine.
D)The three phosphates are sequentially donated to glucose.
E)The three phosphates are used to make new bonds between the nucleotides in DNA.

Question 22

The type of covalent bond that joins amino acids together to form more complex molecules like proteins is called a/an

A)peptide bond
B)ionic bond
C)hydrogen bond
D)nitrogen bond
E)glycosidic bond

Question 23

Which of the following molecules has a structure described as a double helix?

A)mRNA
B)tRNA
C)rRNA
D)DNA
E)ATP

Question 24

The most highly concentrated source of chemical energy found in the human body is found in

A)proteins
B)amino acids
C)glycogen
D)triglycerides
E)glucose

Question 25

Which of the following molecules contains the approximately 30,000 genes found in the cell's nucleus?

A)protein
B)RNA
C)DNA
D)ATP
E)glycogen

Question 26

All of the following are enzymes EXCEPT

A)lactose
B)peptidase
C)oxidase
D)aminopeptidase
E)amylase

Question 27

The building blocks used to assemble complex carbohydrates are called

A)polysaccharides
B)disaccharides
C)monosaccharides
D)glycogen
E)starches

Question 28

The building blocks of proteins are

A)monosaccharides
B)nucleotide
C)amino acids
D)glycerol
E)fatty acids

Question 29

The building blocks of triglycerides are

A)fatty acids and glycerol
B)cholesterol and glycerol
C)monosaccharides
D)amino acids
E)fatty acids, glycerol and phosphate-containing group

Question 30

All of the following statements about enzymes are true EXCEPT

A)the presence of enzyme speeds up chemical reactions.
B)most enzymes are proteins.
C)enzymes are highly specific in the reactions that they catalyze.
D)enzymes are biological catalysts.
E)enzymes are permanently modified by the chemical reactions in which they participate.

Question 31

Which of the following molecules contains the sugar deoxyribose?

A)RNA
B)DNA
C)ATP
D)ADP
E)AMP

Question 32

The building blocks of nucleic acids are called

A)amino acids
B)fatty acids
C)monosaccharides
D)nucleotides
E)glycerol

Question 33

Certain sex hormones such as estrogens and testosterone are classified chemically as

A)proteins
B)carbohydrates
C)nucleic acids
D)lipids
E)starches

Question 34

When three amino acids are chemically linked by peptide bonds, the result is production of a(n)

A)dipeptide
B)tripeptide
C)triglyceride
D)protein
E)polypeptide

Question 35

Polysaccharides can be broken down into simple sugars by the process of

A)dehydration synthesis
B)hydrogen bonding
C)hydrolysis
D)anabolism
E)none of the choices is correct

Question 36

Estradiol, a sex hormone secreted by the ovaries, is chemically classified as a/an

A)amino acid
B)steroid
C)protein
D)enzyme
E)nucleic acid

Question 37

In the human body, glycogen is commonly stored in the cells of the

A)brain
B)liver
C)smooth muscles
D)brain and liver
E)liver and skeletal muscles

Question 38

To prevent rapid, drastic changes in the pH of body fluids, the body

A)uses digestive enzymes.
B)increases lipid production.
C)creates ATP.
D)uses chemical compounds called buffers.
E)changes its temperature.

Question 39

A polysaccharide that serves as common storage form of energy in liver and muscle cells is called

A)fructose
B)glycogen
C)fat
D)starch
E)glycerol

Question 40

Unsaturated fatty acids are commonly found in all of the following EXCEPT

A)regular dairy products
B)olive oil
C)sunflower oil
D)canola oil
E)corn oil

Question 41

The two strands of DNA are held together by

A)peptide bonds between the nitrogenous bases.
B)hydrogen bonds between complementary bases.
C)ionic bonds between the phosphates.
D)polar covalent bonds between the bases.
E)glycosidic linkages between deoxyribose molecules.

Question 42

Which of the following is NOT a nitrogenous base found in DNA?

A)guanine
B)thymine
C)uracil
D)cytosine
E)adenine

Question 43

All of the following are lipids commonly found in the human EXCEPT

A)triglyceride
B)cholesterol
C)estradiol
D)albumin
E)phospholipid

Question 44

Which of the following is NOT one of four major elements that make up about 96% of the human body's mass?

A)hydrogen (H)
B)sodium (Na)
C)oxygen (O)
D)carbon (C)
E)nitrogen (N)

Question 45

The chemical symbol for iron is

A)K
B)Na
C)I
D)Fe
E)Mg

Question 46

Hydrogen atoms often lose an electron from the valence shell to form H⁺. In this ionic form, how many electrons are in the valence electron shell of hydrogen ion?

A)zero
B)one
C)two
D)three
E)four

Question 47

Chemical elements present in high concentrations in the human body are called trace elements.

Question 48

The process in which a protein loses its normal configuration and is no longer able to perform its normal functions due to exposure to heat, chemicals, pH or radiation is called

A)deamination
B)hydrolysis
C)hydrogenation
D)denaturation
E)attenuation

Question 49

Which of the following molecules contains polar covalent bonds?

A)H₂
B)O₂
C)N₂
D)CH₄
E)H₂O

Question 50

What is the smallest complete unit of matter that retains the properties and characteristics of the element?

A)atom
B)molecule
C)proton
D)neutron
E)free radical

Question 51

Which of the following structures are the main locations of ionic bonds in the human body?

A)cartilage and bones
B)teeth and bones
C)ligaments and tendons
D)smooth and cardiac muscles
E)elastic and filamentous connective tissues

Question 52

DNA and RNA are large polymers composed of repeating building blocks called

A)nucleotides
B)amino acids
C)monosaccharides
D)fatty acids
E)phospholipids

Question 53

The mass number of an atom is determined by

A)adding the total number of protons, neutrons and electrons.
B)determining the number of protons in the outer shell.
C)adding the total number of neutrons, protons and proteins.
D)determining the number of protons in the nucleus.
E)adding the total number of protons and neutrons.

Question 54

Which of the following is NOT true about herbal supplements?

A)they can come from any part of a plant
B)they can be useful
C)they can be toxic
D)they should always be avoided
E)they are natural

Question 55

Which property of water makes it important in the breakdown of organic chemicals like our nutrients?

A)Water requires a large amount of heat to change state.
B)Water serves as a lubricant.
C)Water releases heat very slowly.
D)Water participates in chemical reactions.
E)None of the choices is correct.

Question 56

Which of the following structural components are found in both phospholipids and triglycerides?

A)glycerol backbone
B)cholesterol ring
C)polar phosphate-containing head group
D)modified amino acid backbone
E)hydrophobic amino acid sidechains

Question 57

Which of the following particles is found in the atomic nucleus?

A)protons only
B)protons and neutrons
C)protons, neutrons and electrons
D)DNA and RNA
E)none of the choices is correct

Question 58

In addition to the four major elements, there are an additional ___ lesser elements that make up approximately 3.6% of the body's mass.

A)3
B)4
C)8
D)10
E)14

Question 59

An inorganic substance that dissociates into one or more hydroxyl (OH-)ions is classified as a/an

A)acid
B)salt
C)solvent
D)base
E)carbohydrate

Question 60

Which of the following chemical reactions is a synthesis reaction?

A)AB + CD → AC + BD
B)A + B → AB
C)AB → A + B
D)acid + base → salt + water
E)none of the choices represents a synthesis reaction

Question 61

A change in the shape of a protein that results in loss of function is called denaturation.

Question 62

Anything that occupies space and has mass is considered to be _____.

Question 63

Carbohydrates are composed of carbon, hydrogen, and oxygen atoms usually in a ratio of 1:2:1.

Question 64

Hydrogen bonding between different parts of large molecules like proteins and DNA helps determine the molecule's three-dimensional shape.

Question 65

If a dietary supplement is natural, then it is always safe.

Question 66

A solution with a pH of 7 is slightly basic.

Question 67

Dietary supplements often more closely resemble drugs than food in the effects that they produce when ingested.

Question 68

Decomposition reactions involve the breaking of chemical bonds.

Question 69

Inorganic compounds always contain carbon.

Question 70

A full second electron shell of an atom holds only six electrons.

Question 71

A covalent bond is more stable and harder to break than a hydrogen bond.

Question 72

Cholesterol is used to produce some sex hormones.

Question 73

The combination of a solvent and a solution is called a solute.

Question 74

Glycogen is a monosaccharide.

Question 75

Certain types of unsaturated fats are beneficial to our health.

Question 76

The four nitrogenous bases found in DNA are adenine, thymine, cytosine and uracil.

Question 77

Water requires a large amount of heat to change from a liquid to a gas.

Question 78

Chemistry is the study of the structure and interactions of matter.

Question 79

A compound is a molecule composed of two or more different elements.

Question 80

All atoms of a specific element contain the same number of protons.