Deck 2: The Chemistry of Life

Question 1

The high heat capacity of water makes it a very ineffective coolant.

Answer 1

False

Question 2

Molecules composed of two or more atoms are called compounds.

Answer 2

False

Question 3

Potassium, sodium, and chlorine are trace elements.

Answer 3

False

Question 4

A solution is a mixture composed of two or more substances that are physically blended but not
chemically combined.

Question 5

The opposite of a dehydration synthesis is a hydrolysis.

Question 6

Consider oxygen, which has an atomic number of 8 and an atomic mass of 16.How many valence electrons does it have?

A)2
B)4
C)6
D)8
E)16

Question 7

Hydrogen, deuterium, and tritium are three isotopes of hydrogen.

Question 8

All the chemical reactions in which larger molecules are broken down to smaller ones are called catabolic reactions.

Question 9

The most abundant element in the human body, by weight, is

A)nitrogen.
B)hydrogen.
C)carbon.
D)oxygen.
E)calcium.

Question 10

Unsaturated fatty acids have as much hydrogen as they can carry.

Question 11

All amino acids have both a carboxyl group and an amino group attached to a central carbon.

Question 12

ATP is the body's most important form of long-term energy storage.

Question 13

In an exchange reaction, covalent bonds are broken and new covalent bonds are formed.

Question 14

Blood pH is approximately 7.4, which is slightly acidic.

Question 15

Minerals are organic elements extracted from the soil by plants.

Question 16

The chemical properties of an atom are determined by its

A)protons.
B)electrons.
C)neutrons.
D)protons and neutrons.
E)particles.

Question 17

When these two atoms react, both become stable.To become stable, sodium will , while chlorine will .

A)accept one electron; give up one electron
B)give up one proton; accept one proton
C)share one electron with chlorine; share one electron with sodium
D)become an anion; become a cation
E)give up one electron; accept one electron

Question 18

A dipeptide is a molecule with two peptide bonds.

Question 19

Sodium has an atomic number of 11 and an atomic mass of 23.Sodium has

A)12 neutrons and 11 protons.
B)12 protons and 11 neutrons.
C)12 electrons and 11 neutrons.
D)12 protons and 11 electrons.
E)12 electrons and 11 protons.

Question 20

Ionic bonds break apart in water more easily than covalent bonds do.

Question 21

Which of these is the most appropriate to express number of molecules per volume?

A)molarity
B)volume
C)percentage
D)weight per volume
E)milliequivalents per liter

Question 22

Any chemical reaction that removes electrons from an atom is called

A)reduction.
B)condensation.
C)hydrolysis.
D)anabolism.
E)oxidation.

Question 23

Oxygen has an atomic number of eight.When two oxygen atoms come together, they form a(n) bond.

A)hydrogen
B)nonpolar covalent
C)polar covalent
D)ionic
E)Van der Waals

Question 24

Consider a mixture of blood, which contains sodium chloride, protein, and cells or formed elements. The sodium chloride is in a(n) , the protein is in a(n) , and the cells are in a
)

A)emulsion; solution; suspension
B)solvent; emulsion; colloid
C)colloid; suspension; solution
D)suspension; colloid; solution
E)solution; colloid; suspension

Question 25

The breakdown of glycogen (an energy-storage compound) is an example of a(n) reaction.

A)exergonic
B)endergonic
C)exchange
D)synthesis
E)equilibrium

Question 26

Which of these has the highest H+ concentration?

A)lemon juice, pH = 2.3
B)red wine, pH = 3.2
C)tomato juice, pH = 4.7
D)saliva, pH = 6.6
E)household ammonia, pH = 10.8

Question 27

When ATP breaks down to ADP, potential energy stored in bonds is released.This energy stored in bonds is energy.

A)electromagnetic
B)electrical
C)chemical
D)heat
E)kinetic

Question 28

Blood has a pH ranging from 7.35 to 7.45.Slight deviations from this can cause major problems, even death.You are doing an intense workout, and your skeletal muscle cells are producing metabolic acids such as lactic acid.Your blood pH does not drop significantly in spite of the metabolic acids released into the blood.You maintain a constant blood pH because

A)metabolic acids are neutralized in muscle cells before released into the blood.
B)metabolic bases are produced at the same rate by muscle cells to neutralize the acids.
C)the respiratory system removes excess H+ from the blood before the pH is lowered.
D)the body contains chemicals called buffers that resist changes in pH.
E)endothelial cells secrete excess H+ to prevent a decrease in pH.

Question 29

Which one of the following would not increase the rate of a reaction?

A)reactants being more concentrated
B)rise in temperature
C)presence of a catalyst
D)presence of an enzyme
E)decrease in reactant concentrations

Question 30

Glucose is broken down in most of your cells to form carbon dioxide, oxygen, and the energy currency of the cell called ATP.What type of chemical reaction is this?

A)anabolic or endergonic
B)catabolic or exergonic
C)anabolic or exergonic
D)catabolic or endergonic
E)anabolic or exothermic

Question 31

account for 98.5% of the body's weight.

A)Carbon, oxygen, hydrogen, sodium, potassium, and chlorine
B)Carbon, oxygen, iron, sodium, potassium, and chlorine
C)Carbon, nitrogen, hydrogen, sodium, potassium, and chlorine
D)Carbon, oxygen, hydrogen, nitrogen, sodium, and potassium
E)Carbon, oxygen, hydrogen, nitrogen, calcium, and phosphorus

Question 32

A solution that resists a change in pH when acid or base is added to it is

A)a buffer.
B)a catalyst.
C)a reducing agent.
D)an oxidizing agent.
E)a colloid.

Question 33

Which of these is a cation?

A)O₂
B)K
C)Na
D)Ca₂+
E)Cl-

Question 34

A solution with pH 4 has the H+ concentration of a solution with pH 8.

A)½
B)twice
C)4 times
D)10,000 times
E)1/10,000

Question 35

The bonding properties of an atom are determined by its

A)electrons.
B)protons.
C)positrons.
D)neutrons.
E)photons.

Question 36

What type of bond attracts one water molecule to another?

A)an ionic bond
B)a peptide bond
C)a hydrogen bond
D)a covalent bond
E)a hydrolytic bond

Question 37

The most relevant free energy in human physiology is the energy stored in

A)electrolytes ionized in water.
B)free radicals with an odd number of electrons.
C)radioisotopes.
D)the chemical bonds of organic molecules.
E)Van der Waals forces.

Question 38

When you jump off a high diving board into water, you notice great resistance of water.This resistance is called and is caused by water's great .

A)surface tension; adhesiveness
B)surface tension; cohesiveness
C)hydrophobic tension; adhesiveness
D)hydrophilic tension; cohesiveness
E)hydrophilic tension; adhesiveness

Question 39

Varieties of elements called differ from one another only in number of neutrons and therefore in atomic mass.

A)cations
B)anions
C)isotopes
D)electrolytes
E)free radicals

Question 40

Which of these is hydrophobic?

A)sugar
B)K+
C)Cl-
D)water
E)fat

Question 41

The folding and coiling of proteins into globular and fibrous shapes determines the structure of the protein.

A)primary
B)secondary
C)tertiary
D)quaternary
E)denatured

Question 42

A(n) is a group of atoms that determines many of the properties of an organic molecule.

A)carboxyl group
B)functional group
C)hydroxyl group
D)amino group
E)phosphate group

Question 43

are major components of cell membranes, and are said to be .

A)Triglycerides; hydrophobic
B)Steroids; hydrophilic
C)Bile acids; fat-soluble
D)Eicosanoids; water-soluble
E)Phospholipids; amphiphilic

Question 44

A converts a to its monomers.

A)hydrolysis; polymer
B)dehydration synthesis; molecule
C)dehydration synthesis; polymer
D)polymer; molecule
E)condensation; reactant

Question 45

is the substrate of .

A)Glucose; lactose
B)Lactase; glucose
C)Lactose; lactase
D)Galactose; lactose
E)Sucrase; sucrose

Question 46

Triglycerides are molecules consisting of one 3-carbon compound called bound to three .

A)eicosanoid; fatty acids
B)steroid; glycerols
C)eicosanoid; steroid
D)glycerol; fatty acids
E)steroid; fatty acids

Question 47

Enzymes are specific to substrates because of the shape of their

A)active sites.
B)receptors.
C)secondary structure.
D)terminal amino acids.
E)alpha chain.

Question 48

Table sugar is a disaccharide called and is made up of the monomer(s) .

A)maltose; glucose
B)sucrose; glucose and fructose
C)lactose; glucose and galactose
D)glycogen; glucose
E)glucose; galactose and fructose

Question 49

A drastic conformational change in proteins in response to conditions such as extreme heat or pH will lead to loss of a protein's function.This drastic change in three-dimensional shape is called

A)contamination.
B)denaturation.
C)saturation.
D)sedimentation.
E)deconformation.

Question 50

Which of the following is a disaccharide?

A)galactose
B)lactose
C)glucose
D)fructose
E)amylose

Question 51

Proteoglycans are macromolecules that form gels, which help hold cells and tissues together, lubricate joints, and account for the tough rubbery texture of cartilage.Proteoglycans are composed of

A)carbohydrates and fats.
B)nucleic acids and fats.
C)carbohydrates and proteins.
D)proteins and fats.
E)nucleic acids and proteins.

Question 52

The formula for an amino group is whereas the formula of a carboxyl group is

A)-COOH; -OH.
B)-CH3; -NH₂.
C)-OH; -SH.
D)-NH₂; -COOH.
E)-SH; -H₂PO₄.

Question 53

Proteins can serve all of the following functions except

A)catalyze metabolic reactions.
B)give structural strength to cells and tissues.
C)produce muscular and other forms of movement.
D)regulate transport of solutes into and out of cells.
E)store hereditary information.

Question 54

Which of the following equations depicts an exchange reaction?

A)AB → A + B
B)A + B → AB
C)AB + CD → AC + BD
D)AB → A- + B+
E)A + B → AB → C + D

Question 55

Which of the following words includes all of the other terms?

A)catabolism
B)anabolism
C)metabolism
D)oxidative reactions
E)reductive reactions

Question 56

In general, have a 2:1 ratio of hydrogen to oxygen.

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

Question 57

Which of these is (are) always hydrophobic?

A)glucose
B)cholesterol
C)amino acids
D)proteins
E)disaccharides

Question 58

is a monosaccharide, whereas is a polysaccharide.

A)Fructose; sucrose
B)Galactose; maltose
C)Lactose; glycogen
D)Glucose; starch
E)Cellulose; glucose

Question 59

Digestive enzymes breakdown the starch in a potato into thousands of glucose molecules.This exemplifies a(n) reaction.

A)synthesis
B)decomposition
C)exchange
D)anabolic
E)reductive

Question 60

Proteins are built from different amino acids.

A)monomers; 10
B)molecules; 10
C)polymers; 20
D)macromolecules; 40
E)polypeptides; 80

Question 61

All enzymes are , but not all of those are enzymes.

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

Question 62

ATP endergonic and exergonic reactions.

A)opposes
B)decomposes
C)reduces
D)links
E)dehydrates

Question 63

Nucleic acids are of .

A)molecules; monosaccharides
B)monomers; ATP
C)polymers; nucleotides
D)polymers; cAMP
E)polymers; DNA