Deck 2: The Chemistry of Life

Question 1

Identify the reactants in the following chemical reaction: C₁₀H₈ + 12 O₂ → 10 CO₂ + 4 H₂O

A)C₁₀H₈ and 10 CO₂
B)12 O₂ and 4 H₂O
C)C₁₀H₈ and 12 O₂
D)10 CO₂ and 4 H₂O

Answer 1

C

Question 2

The 2+ in Cu²⁺ tells us that this atom ________.

A)has two more neutrons than protons
B)has two more protons than electrons
C)has two more electrons than neutrons
D)has two more electrons than protons

Answer 2

B

Question 3

In chemical bonding,when the bonded atoms share electrons,it is specifically called ________.

A)an ionic bond
B)a covalent bond
C)a hydrogen bond
D)a polar bond

Answer 3

B

Question 4

What is a trace element?

A)An element that is very rare
B)An element that is evenly distributed on the planet
C)An element that is required in miniscule amounts for life
D)An element that is used to identify the location of other elements

Question 5

How many neutrons in a carbon-14 atom?

A)6
B)7
C)8
D)14

Question 6

If the number of protons in an atom does not match the number of electrons,the atom is specifically called an ________.

A)element
B)isotope
C)isomer
D)ion

Question 7

The majority of the elements essential to life are found in what part of the periodic table?

A)The top third
B)The middle third
C)The bottom third
D)Evenly distributed throughout the periodic table

Question 8

What is the most common element in your body?

A)Oxygen
B)Water
C)Carbon
D)Sugar

Question 9

What is the maximum number of single covalent bonds a carbon atom can form with other elements?

A)1
B)2
C)3
D)4

Question 10

While the maximum number of electrons required to fill the outermost shell of an atom varies depending on the size of the atom,almost all of the smaller atoms (atomic numbers 2-20)are considered stable (nonreactive)when they contain ________ electron(s)in the outermost shell.

A)1
B)2
C)8
D)16

Question 11

How many HCl molecules are required to balance the following reaction? Zn + ___ HCl → ZnCl₂ + H₂

A)1
B)2
C)3
D)4

Question 12

The typical carbon atom is described in the periodic table by the accompanying box.How many protons are in a typical carbon atom?

A)6
B)12
C)18
D)Not enough information given

Question 13

The chemical name for table salt is sodium chloride,or simply NaCl.What type of chemical is NaCl?

A)Compound
B)Element
C)Molecule
D)Ion

Question 14

What is the maximum number of electrons that can fit into the innermost shell of an atom?

A)1
B)2
C)8
D)16

Question 15

Identify the part of the atom that most determines the chemical reactivity of the atom.

A)The number of shells
B)The number of protons
C)The number of neutrons
D)The number of electrons

Question 16

Which number represents the atomic weight of carbon?

A)6
B)12
C)18
D)Not enough information given

Question 17

Individual water molecules are held to one another by relatively weak ________ bonds.

A)covalent
B)hydrogen
C)ionic
D)nonpolar

Question 18

Which is not one of the four atoms that make up the bulk of living organisms?

A)Oxygen
B)Nitrogen
C)Calcium
D)Carbon

Question 19

How many neutrons are in a typical carbon atom?

A)6
B)12
C)18
D)Not enough information given

Question 20

The electronegativity of an atom is determined by how strongly outermost electrons are pulled toward the nucleus.Somewhat like gravity,the electronegativity will be stronger in atoms with larger nuclei and closer outermost electrons.Which element has the strongest electronegativity?

A)Boron
B)Carbon
C)Nitrogen
D)Oxygen

Question 21

Why is one side of a water molecule partially negative while the other side is partially positive?

A)Uneven sharing of electron pairs occurs due to the strong pull of hydrogen.
B)Uneven sharing of electron pairs occurs due to the strong pull of oxygen.
C)Oxygen donates its electrons to hydrogen.
D)Hydrogen donates its electrons to oxygen.

Question 22

A needle can be made to "float" on the surface tension of water.What causes this surface tension to form?

A)The adhesion of water molecules to the needle
B)The cohesion of water molecules to each other
C)The solubility of water
D)The heat capacity of water

Question 23

Which of the following large organic molecules includes table sugar?

A)Carbohydrates
B)Lipids
C)Proteins
D)Nucleic acids

Question 24

The difference in pH units between two acidic solutions is three.How much more acidic is the stronger acid than the weaker acid?

A)3 times more acidic
B)30 times more acidic
C)100 times more acidic
D)1,000 times more acidic

Question 25

Which polysaccharide consists of individual long,twisted,unbranched chains of glucose?

A)Starch
B)Cellulose
C)Glycogen
D)This does not describe a polysaccharide.

Question 26

What are the monomers of proteins?

A)Hydrochloric acids
B)Nucleic acids
C)Carboxylic acids
D)Amino acids

Question 27

Which of the following is not made from long chains of glucose?

A)Starch
B)Glycerol
C)Glycogen
D)Cellulose

Question 28

The functional group -NH₂ is called the ________ group.

A)methyl
B)alcohol
C)amino
D)carboxyl

Question 29

What is another name for the polymers of carbohydrates?

A)Triglycerides
B)Polysaccharides
C)Polypeptides
D)Nucleotides

Question 30

Water is the lightest (least dense)when it ________.

A)freezes
B)is just above freezing
C)is at room temperature
D)is just below boiling

Question 31

Something with a pH of 5 would be ________.

A)acidic
B)basic
C)neutral
D)alkaline

Question 32

How do buffers minimize change in the pH of biological systems?

A)By absorbing H⁺ ions when there is an excess
B)By donating H⁺ ions when there is a shortage
C)Both of these
D)Neither of these

Question 33

Which polysaccharide consists of many long straight chains of glucose with bonds joining the chains?

A)Starch
B)Cellulose
C)Glycogen
D)This does not describe a polysaccharide.

Question 34

What is the sum total of all the chemical reactions that take place in your body called?

A)Catabolism
B)Anabolism
C)Embolism
D)Metabolism

Question 35

Based on the suffix,a molecule of "maltose" is most likely what type of macromolecule?

A)Carbohydrate
B)Lipid
C)Protein
D)Nucleic acid

Question 36

If you remove all of the functional groups from an organic molecule such that it contains only carbon and hydrogen atoms,the molecule is called ________.

A)a carbohydrate
B)an inorganic molecule
C)a hydrocarbon
D)polar

Question 37

The breaking of a large organic molecule into smaller individual subunits involves multiple ________.

A)hydrolysis reactions
B)osmotic reactions
C)dehydration synthesis reactions
D)hydrosynthetic reactions

Question 38

Water "beads up" on synthetic fabric like polyester but binds to cotton.What is the most likely explanation for this?

A)Polyester is not a naturally occurring substance,whereas cotton is a naturally occurring substance.
B)Polyester is more flexible than cotton.
C)Polyester fibers are thinner than cotton fibers.
D)Polyester is nonpolar,whereas cotton is polar.

Question 39

Select the most complete explanation of what the pH scale actually measures.

A)The acidity of a solvent
B)The alkalinity of a solvent
C)The concentration of hydrogen ions in a solution
D)The concentration of hydroxide ions in a solute

Question 40

Lipids are all ________.

A)hydrophonic
B)hydrophilic
C)hydrophobic
D)hydrolytic

Question 41

Proteins are diverse molecules that perform a wide variety of functions.Which of the following is not a typical function of proteins?

A)Defense
B)Catalyze reactions
C)Movement
D)Energy storage

Question 42

Organic molecules that end in the suffix "-ase" often function as ________ molecules.

A)structural
B)enzymatic
C)transport
D)storage

Question 43

Why does sweating cool your skin on a hot,dry day but makes you feel warmer on a hot,humid day?

Question 44

An old home remedy for anemia was to drink from a jug of water into which was added a handful of iron nails.Why might this have been effective at treating certain forms of anemia?

Question 45

Individual amino acids have unique chemical qualities but these do not directly determine the function of an enzyme.What then is the role of the individual amino acid's unique chemical qualities and what then directly determines the function of an enzyme?

Question 46

What will be accomplished by lowering the activation energy of a reaction?

A)The reaction will proceed more slowly.
B)The reaction will proceed more quickly.
C)The reaction will stop completely.
D)The reaction will reverse.

Question 47

Which of the three gasses is the easiest to break apart,nitrogen gas (N₂),oxygen gas (O₂),or hydrogen gas (H₂)? Which is the most difficult to break apart? What accounts for the differences?

Question 48

Penicillin is a competitive inhibitor produced by a fungus in order to kill invading bacteria.It does this by mimicking the substrate required by the bacterium to build and repair its cell wall.Describe how mimicking the substrate would result in the death of the bacterium.

Question 49

To a large extent,a protein's function is dependent upon its shape.What determines a protein's shape?

A)The location of the active site
B)The sequence of amino acids
C)The concentration of carbon-to-hydrogen single bonds
D)The number of carbon-to-carbon double bonds

Question 50

Which would have the highest concentration of C-H bonds?

A)Saturated fat
B)Unsaturated fat
C)Trans fat
D)Cholesterol

Question 51

Which combination describes the plasma membrane?

A)Hydrophilic interior,hydrophobic exterior
B)Hydrophilic interior and exterior
C)Hydrophobic interior,hydrophilic exterior
D)Hydrophobic interior and exterior

Question 52

Identify the substrate in the following reaction: Sucrose → Fructose + Glucose

A)Sucrose
B)Fructose
C)Glucose
D)Fructose and glucose

Question 53

What is the basic structure of most lipids?

A)A glycerol head and up to three fatty acid tails
B)A linear chain of individual monomers
C)A branched chain of individual monomers
D)A ring with carbon,hydrogen,and oxygen in a 1:2:1 ratio

Question 54

What gives an amino acid its unique chemical properties?

A)The different amino groups
B)The sequence of amino acids in a chain
C)The bond that forms between amino acids
D)The side group

Question 55

Oil hydrogenation can produce a product,such as vegetable shortening or margarine,that is spreadable at room temperature.What is the name of this category of lipid?

A)Saturated fat
B)Unsaturated fat
C)Trans fat
D)Cholesterol

Question 56

Which of the following dietary fats is considered to be the most healthy?

A)Saturated fat
B)Unsaturated fat
C)Trans fat
D)Cholesterol

Question 57

What might lead to a protein that does not function properly?

A)Incorrect folding of the amino acid chain
B)The active site becoming blocked
C)The active site becoming distorted
D)All of these