Deck 2: The Chemistry of Biology

Question 1

Polar molecules are composed of covalently-bonded

A) identical atoms.
B) carbon atoms.
C) ions.
D) atoms of different electronegativity.
E) atoms of identical electronegativity.

Answer 1

D

Question 2

Compared to a solution of pH 9, a solution of pH 7

A) is more basic.
B) has no OH^- ions.
C) has more H⁺ ions.
D) has a higher pH.
E) All of these choices are correct.

Answer 2

C

Question 3

Isotopes are atoms of the same element that differ in their

A) neutron number.
B) electron number.
C) proton number.
D) atomic number.
E) chemical properties.

Answer 3

A

Question 4

Which term does not belong in this list?

A) lactic acid
B) vinegar
C) hydrogen ion donor
D) pH 8
E) acidic

Question 5

The subatomic particles that surround the nucleus are the

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

Question 6

Which of the following represents a synthesis reaction?

A) AB → A + B
B) A + B → AB
C) AB + XY → AX + BY
D) AB + XY ↔ AX + BY

Question 7

Cations are

A) charged subatomic particles.
B) atoms that have gained electrons.
C) radioactive isotopes.
D) capable of forming ionic bonds with anions.
E) atoms without protons.

Question 8

Anything that occupies space and has mass is called

A) an electron.
B) living.
C) matter.
D) energy.
E) space.

Question 9

The building blocks of an enzyme are

A) nucleotides.
B) glycerol and fatty acids.
C) monosaccharides.
D) phosphate, glycerol, fatty acids.
E) amino acids.

Question 10

Reactions involving electron removal are called ______ reactions.

A) oxidation
B) reduction
C) dehydration
D) decomposition
E) dissolution

Question 11

What would be the valence number of electrons in the sulfur atom ³²₁₆S?

A) 2
B) 6
C) 8
D) 16
E) 32

Question 12

What do H₂O, NaCl, CO₂, and HCl all have in common?

A) All are salts.
B) All are acids.
C) All are gases.
D) All are inorganic.
E) All are solutes.

Question 13

All of the following are lipids except

A) cholesterol.
B) starch.
C) phospholipid.
D) wax.
E) triglyceride.

Question 14

All of the following pertain to ¹⁴₆C except it

A) has 6 protons.
B) has 6 electrons.
C) has 14 neutrons.
D) is an isotope of carbon.
E) has a mass number of 14.

Question 15

The important solvent associated with living things is

A) carbon dioxide.
B) sodium chloride.
C) ethyl alcohol.
D) benzene.
E) water.

Question 16

All of the following are monosaccharides except

A) glucose.
B) glycogen.
C) fructose.
D) ribose.
E) deoxyribose.

Question 17

Two or more atoms bonded together are called a/an

A) ion.
B) isotope.
C) element.
D) electrolyte.
E) molecule.

Question 18

What is the maximum number of electrons in the second energy shell of an atom?

A) 2
B) 4
C) 8
D) 18
E) 32

Question 19

The electrons of an atom are

A) always equal in number to the number of neutrons in an atom.
B) found in the nucleus.
C) used to determine atomic number.
D) positively charged.
E) moving in pathways called orbitals.

Question 20

Which of the following functional groups is mismatched to the organic compound?

A) phosphate - carbohydrates
B) sulfhydryl - proteins
C) amino - proteins
D) hydroxyl - alcohols
E) carboxyl - fatty acids

Question 21

The weak, attractive force between water molecules is due to

A) hydrogen bonds.
B) covalent bonds.
C) ionic bonds.
D) peptide bonds.
E) glycosidic bonds.

Question 22

Which of the following would have glycosidic bonds?

A) triglycerides
B) monosaccharides
C) polypeptides
D) polysaccharides
E) ATP

Question 23

The nucleic acid that delivers the correct amino acid to the ribosome for protein synthesis is

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

Question 24

One nucleotide contains

A) one phosphate.
B) one pentose.
C) one nitrogen base.
D) All of these choices are correct.

Question 25

An amino acid contains all of the following except

A) an amino group.
B) a carboxyl group.
C) a variable R group.
D) a carbon atom.
E) a nitrogenous base.

Question 26

Jim needs to prepare one liter of a 4% NaCl solution. How much NaCl should he weigh out?

A) 0.4 grams
B) 4.0 grams
C) 40 grams
D) 400 grams

Question 27

A student forgot to label a beaker containing a DNA solution and a beaker containing a glucose solution. If chemical analysis was performed to identify the contents of each beaker, which of the following would be found in the beaker of DNA but not in the beaker with glucose?

A) amino acids
B) hydrogen and oxygen atoms
C) nitrogen and phosphorus
D) fatty acids
E) carbon atoms

Question 28

The purine bases in nucleic acids include

A) thymine and cytosine.
B) guanine and adenine.
C) cytosine and guanine.
D) adenine and thymine.
E) ribose and deoxyribose.

Question 29

Which amino acid contains sulfur atoms that form covalent disulfide bonds and stabilize the tertiary structure of some proteins?

A) valine
B) cysteine
C) serine
D) alanine
E) tyrosine

Question 30

All of the following are polysaccharides, except

A) dextran in some bacterial slime layers.
B) agar used to make solid culture media.
C) a cell's glycocalyx.
D) cellulose in certain cell walls.
E) prostaglandins in inflammation.

Question 31

Which of the following represents an exchange reaction?

A) AB → A + B
B) A + B → AB
C) X + Y → XYD
D) AB + XY ↔ AX + BY

Question 32

Which of the following is found in DNA but not in RNA?

A) ribose
B) adenine
C) thymine
D) uracil
E) nucleotides

Question 33

The hydrophobic tails of a phospholipid are composed of

A) fatty acids.
B) glycerol.
C) phosphate.
D) alcohol.
E) All of these choices are correct.

Question 34

If carbon has an atomic number of 6 and an atomic mass of 14, how many neutrons does it have?

A) 6
B) 7
C) 8
D) 14
E) There is not enough information to determine this.

Question 35

The neutrons of an atom are

A) always equal to the number of protons in an atom.
B) found in the nucleus.
C) used to determine atomic number.
D) positively charged.
E) moving in pathways called orbitals.

Question 36

C₆H₁₂O₆ + C₆H₁₂O₆ →C₁₂H₂₂O₁₁ + H₂O is an example of

A) formation of a peptide bond.
B) a decomposition reaction.
C) denaturation.
D) a hydrolytic reaction.
E) dehydration synthesis.

Question 37

Which is not true about enzymes?

A) Enzymes are found in all cells.
B) Enzymes are catalysts.
C) Enzymes participate in the cell's chemical reactions.
D) Enzymes can be denatured by heat and other agents.
E) Enzymes have high-energy bonds between phosphates.

Question 38

The atomic number equals the number of __________ in an atom.

A) neutrons
B) protons
C) protons plus electrons
D) neutrons plus protons

Question 39

A monosaccharide with 5 carbon atoms will have _____ hydrogen atoms and _____ oxygen atoms.

A) 10; 5
B) 5; 10
C) 5; 5
D) 10; 10
E) 2; 1

Question 40

ATP is best described as

A) an enzyme.
B) a double helix.
C) an electron carrier.
D) the energy molecule of cells.
E) All of these choices are correct.

Question 41

Which of the following functional groups participate in the formation of an ester bond?

A) hydroxyl group and amino group
B) carboxyl group and amino group
C) hydroxyl group and carboxyl group
D) hydroxyl group and carbonyl group

Question 42

All proteins are enzymes.

Question 43

Which of the following is/are hydrophilic?

A) glucose
B) vegetable oil
C) butter
D) cholesterol
E) Vegetable oil, butter, and cholesterol are correct.

Question 44

How many times more acidic is a solution with a pH of 3 than a solution with a pH of 6?

A) 3
B) 10
C) 1000
D) 36
E) 63

Question 45

Elements have predictable chemical properties.

Question 46

Water molecules are nonpolar molecules.

Question 47

Which of the following is the stored form of carbohydrates in animals?

A) glycogen
B) maltose
C) starch
D) cellulose
E) galactose

Question 48

If solution A has a lower pH compared to solution B, then solution A is more acidic than solution
B.

Question 49

The alpha helix and beta pleated sheet are examples of

A) primary structure.
B) secondary structure.
C) tertiary structure.
D) quaternary structure.
E) gamma structure.

Question 50

53. Only charged atoms can form ionic bonds.

Question 51

The concentration of a solution expresses the amount of solvent present.

Question 52

Electrons that participate in chemical bonding are typically located closest to the nucleus.

Question 53

The polynucleotide strands of DNA are linked along their length by __________ bonds between the bases.

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

Question 54

Which of the following carbohydrates is found in dairy products?

A) lactose
B) sucrose
C) maltose
D) glucose
E) fructose

Question 55

The chemical reaction that forms an ester bond in a triglyceride is a __________________ reaction.

A) dehydration synthesis
B) oxidation
C) hydrolysis
D) reduction

Question 56

A covalent bond is formed between an anion and a cation.

Question 57

All of the following are correct about triglycerides, except

A) triglycerides are insoluble in water.
B) triglycerides are a concentrated source of energy.
C) unsaturated triglycerides are solid at room temperature.
D) triglycerides dissolve in nonpolar solvents.
E) triglycerides are hydrolyzed by lipases.

Question 58

Polar molecules have more reactivity compared to nonpolar molecules.

Question 59

The type of chemical bond linking amino acids together is an)

A) glycosidic bond.
B) peptide bond.
C) ester bond.
D) ionic bond.
E) hydrogen bond.

Question 60

The only part of an amino acid that differs from other amino acids is its R group.

Question 61

Select the incorrect statement.

A) Molecules contain atoms.
B) Compounds may contain only one type of atom.
C) Compounds contain molecules.
D) Atoms are joined by chemical bonds forming molecules.
E) Molecules may contain two of the same type of atom.

Question 62

Certain antibiotics are effective against bacteria that cause human infections because they target prokaryotic ribosomes. Discuss, in detail, how the drug attacking a pathogen's ribosomes will affect the cell. Discuss at least three specific detrimental results.

Question 63

A solution is composed of one or more substances called _____ that are uniformly dispersed in a dissolving medium called a _____.

Question 64

Atoms that gain or lose electrons become charged particles called _____.

Question 65

During cellular reactions, electrons may be removed from compounds such as glucose and picked up by a coenzyme known as NAD⁺. When NAD⁺ gains these electrons, it is said to be

A) oxidized.
B) reduced.
C) synthesized.
D) dehydrated.

Question 66

During protein synthesis, genes in DNA are copied, making _____ RNA.

Question 67

Organic chemicals always have a basic framework of the element _____ bonded to other atoms.

Question 68

Nucleic acids have primary, secondary, tertiary, and quaternary levels of organization.

Question 69

Which elements are found in all carbohydrates, lipids, proteins, and nucleic acids?

Question 70

Chemical analysis of an unidentified compound isolated from cells showed the presence of carbon, hydrogen, oxygen, nitrogen, and sulfur. This unknown compound is most likely a

A) carbohydrate.
B) nucleic acid.
C) lipid.
D) protein.

Question 71

Replication is the cellular process that copies the DNA prior to cell division.

Question 72

Identify and provide specific examples of the classes of macromolecules that are associated with life.

Question 73

A fat is called _____ if all carbons of the fatty acid chain are single bonded to 2 other carbons and 2 hydrogens.

Question 74

Compare and contrast the chemical and functional characteristics of DNA and RNA molecules.

Question 75

_____ bonds are formed by dehydration synthesis between adjacent amino acids.

Question 76

Protons and neutrons make up the atom's central core referred to as its _____.

Question 77

The total number of protons and neutrons of an element establishes its _____ number.

Question 78

Purines and pyrimidines are components in the building block units of all _____

Question 79

Water, glucose, and carbon dioxide are examples of

A) compounds.
B) atoms.
C) gases.
D) macromolecules.

Question 80

Explain what radioisotopes are, and describe how they can be used to monitor the uptake of a specific biochemical by a microbial culture.