Bio Lec Exam 1

Question 1

1

Answer 1

False

The classification most commonly used by biologists today contains three domains: Bacteria,
Archaea, Eukarya.

Question 2

2

Answer 2

TRUE

Climate change is primarily due to an imbalance in the chemical cycling of the element carbon.
Normally, carbon is cycled within an ecosystem. However, due to human activities, more carbon
dioxide is being released into the atmosphere than is being removed.

Question 3

3

Answer 3

True

The control group in an experiment receives all the same treatments as the experimental
group(s), except for the one variable being tested

Question 4

4

Answer 4

TRUE

Both abiotic agents (ex. temperature, precipitation) and biotic agents (ex. competition, predation)
can act as selective agents

Question 5

5

Answer 5

FALSE

Carbon has four valence shell electrons which means it needs to share four more electrons to
have a complete valence shell. If it accomplishes this with single covalent bonds, it would need
to share electrons with four other atoms.

Question 6

6

Answer 6

FALSE

Triglycerides are composed of glycerol and three fatty acids. Waxes are long-chain fatty acids
bonded with carbon chains containing alcohol functional groups.

Question 7

7

Answer 7

TRUE

ATP is a nucleotide-based molecule that supplies energy to the cell

Question 8

8

Answer 8

FALSE

Starch is a polysaccharide that stores energy in plant cells.

Question 9

9

Answer 9

FALSE

Migratory birds store energy as fat, since gram per gram, fat stores more energy than glycogen.

Question 9

10

Answer 9

A, C

The additional carbon dioxide that is released into the atmosphere either stays in the atmosphere
and acts as a greenhouse gas or it is dissolved into the oceans where is causes acidification and
coral bleaching.

Question 10

11

Answer 10

[A, B, C]

Biodiversity does not usually increase rapidly over time. Biodiversity in many ecosystems is
presently declining due to climate change and other factors.

Question 11

12

Answer 11

[B, E]

The atomic number of phosphorus is 15. This means it has 15 protons (15 positive charges) and
therefore 15 electrons. The first two electron shells would be full but its valence shell would be
incomplete with 5 out of 8 electrons and therefore it will form chemical bonds with other
elements.

Question 12

13

Answer 12

[A, C]

Oxygen-18 is an isotope of oxygen. Isotopes differ in their number of neutrons. A typical oxygen
has an atomic mass of 16 (8 protons + 8 neutrons), oxygen 18 would still have 8 protons (proton
number does not change) but it would have 10 neutrons.

Question 13

14

Answer 13

[B, C, E]

Carbohydrates are formed from monomer subunits called monosaccharides and consist primarily
of carbon, hydrogen, and oxygen in a 1:2:1 ratio. Starch is a carbohydrate specific to plants and
chitin is found in the exoskeletons of crabs and other similar animals

Question 14

15

Answer 14

C

An ecosystem ecologist studies the interactions and relationships that occur among groups of
species and their physical environment.

Question 15

16

Answer 15

D

A scientific theory or principle is a conceptual scheme in science that is strongly supported, has
not yet been found incorrect, and is based on the results of many observations.

Question 16

17

Answer 16

A

The correct order of classification from most inclusive to most exclusive is: Domain-Kingdom-
Phylum-Class-Order-Family-Genus-Species.

Question 17

18

Answer 17

D

The correct sequence of increasing biological organization is: atom, molecule, organelle, cell.

Question 18

19

Answer 18

D

Single-celled prokaryotes lack a membrane-bounded nucleus, are classified in the domains
Bacteria and Archaea, and are found in almost all habitats. However, they DO NOT contain
organelles such as mitochondria and chloroplasts

Question 19

20

Answer 19

D

A hypothesis is not a guess, it is a tentative explanation based on observation. Therefore,
observation must precede the hypothesis. Once a hypothesis is made, it is tested by
experimentation.

Question 20

21

Answer 20

D

Living organisms are characterized by adaptation to the environment, evolving over time, and
displaying homeostatic controls, however, not all organisms require oxygen to survive. Some
area actually killed by oxygen.

Question 21

22

Answer 21

A

Incorrect Answers:

B. Organisms in domain Archaea are primitive prokaryotes that live in extreme
environments.

C. Organisms in kingdom Plantae are composed of eukaryotic cells. Archaea are primitive
prokaryotes that live in extreme environments.

D. Organisms in kingdom Fungi are composed of eukaryotic cells. Archaea are primitive
prokaryotes that live in extreme environments.

E. Organisms in domain Eukarya are composed of eukaryotic cells. Archaea are primitive
prokaryotes that live in extreme environments.

Question 22

23

Answer 22

B

Question 23

24

Answer 23

D

Question 24

25

Answer 24

C

A prediction is the expected outcome of an experiment based upon the knowledge of the factors
in the experiment.

Question 25

26

Answer 25

D

All of the choices ARE ultimately dependent on the sun. Plants, regardless of the kind of animal
that pollinates them, rely on the sun for photosynthesis. All animals eat plants or they eat other
animals that eat plants. Therefore, they are all dependent on the sun.

Question 26

27

Answer 26

A

Since the researcher is not testing the contribution of a specific variable in relation to the length
and weight of the pine needles, the data is a result of observation.

Question 27

28

Answer 27

B

The control group is not exposed to the experimental variable. In this case, the control group
does not receive either of the antibiotics.

Question 28

29

Answer 28

E

The later classification systems better represent the unity and diversity of life, allow for better
organization of ever-increasing numbers of species, and group organisms based on similarities
related to their structure and evolution. The modern classification system is NOT necessarily
more intuitive than the old one. For example, lizards are cold-blooded, lack feathers, and can’t
fly. Birds are warm-blooded, have feathers and can fly. One might not expect them to be grouped
together but the new classification system puts them in the same group, Reptilia.

Question 29

30

Answer 29

A

Tissues are made of cells and molecules are made of atoms.

Question 30

31

Answer 30

E

The answer choice “Some plants should be given a fertilizer and others no fertilizer” should not
be a consideration in this experiment because it is not one of the variables being tested in the
experiment and adding it to the experimental design would make it difficult to discern the effects
of the variables that are being tested.

Question 31

32

Answer 31

C

Question 32

33

Answer 32

A

This situation describes adaptation to the environment.

Question 33

34

Answer 33

C

It is easier to hold all but one variable constant in a laboratory.

Question 34

35

Answer 34

D

From a science viewpoint, this conclusion may not be valid because it generalizes about all
people, and there may have been other variables that could awaken you without a built-in clock.

Question 35

36

Answer 35

B

The manner in which a scientist intends to conduct an experiment is called the experimental
design.

Question 36

37

Answer 36

A

The levels of ecological study from most inclusive to most exclusive are: biosphere, ecosystem,
community, population, individual organism.

Question 37

38

Answer 37

A

A population consists of all of the individuals of a given species in a particular region.

Question 38

39

Answer 38

E

The answer “includes the entire region of the Earth’s surface that is inhabited by living
organisms” is not a feature of an ecosystem. It is a feature of the biosphere which is a level of
organization above the ecosystem.

Question 39

40

Answer 39

C

Organisms belonging to the same family would be the most closely related.

Question 40

41

Answer 40

A

Science is a systematic way of acquiring information about the natural world.

Question 41

42

Answer 41

A

Technology is the application of scientific knowledge to the interests of humans.

Question 42

43

Answer 42

B

Climate change is primarily due to an imbalance in the chemical cycling of the element carbon.

Question 43

44

Answer 43

44) D

The control group in an experiment receives all the same treatments as the experimental
group(s), except for the one variable being tested.

Question 44

45

Answer 44

45) C
The selective agents for natural selection can be either abiotic or biotic.

Question 45

46

Answer 45

46) A

Question 46

47

Answer 46

47) B

Antacids are bases and by definition can absorb out of a solution.

Question 47

48

Answer 47

48) D

Both cohesion and adhesion explain the movement of water through a paper towel. Cohesion is
holding the water molecules together within the droplet. The water molecules are attracted to the
paper which is adhesion.

Question 48

49

Answer 48

49) B

The number of protons = the atomic number; mass number is protons + neutrons. If the mass 17 + N
number is 35 then . There are 18 neutrons.

Question 49

50

Answer 49

50) E

Energy and half-life are not directly related.

Question 50

51

Answer 50

51) E

Question 51

52

Answer 51

52) B

Question 52

53

Answer 52

53) D

The statement “The hydrogen atoms are more electronegative than the oxygen atom” is incorrect.
The oxygen atoms in the water molecule are more electronegative than the hydrogens.

Question 53

54

Answer 53

54) D

An atom’s atomic mass is the average mass for all the isotopes of that atom.

Question 54

55

Answer 54

55) D

From the symbol that is given, we know this is a hydrogen isotope with one proton and two
neutrons. Hydrogen normally has one proton and no neutrons. Proton number never changes
which means that a hydrogen atom with an atomic mass of 3, must have 1 proton and 2 neutrons.

Question 55

56

Answer 55

56) B

Oxygen atoms can have eight or 10 neutrons. These are the same element.

Question 56

57

Answer 56

57) D

The change occurred because gained a proton. Carbon originally had 6 protons. Once carbon
gains a proton, its atomic number changes from 6 to 7, effectively changing it into nitrogen.

Question 57

58

Answer 57

58) D

Question 58

59

Answer 58

59) B

The valence shell is the outermost electron shell of an atom.

Question 59

60

Answer 59

60) D

Sodium bicarbonate neutralizes stomach acid by combining with excess.

Question 60

61

Answer 60

61) C

Question 61

62

Answer 61

62) A

Question 62

63

Answer 62

63) E

Question 63

64

Answer 63

64) B

The reaction can flow either direction depending on whether there is an excess of hydrogen ions
or not enough hydrogen ions.

Question 64

65

Answer 64

65) A

From the information in the chart, it can inferred that double bonds are stronger than single
bonds

Question 65

66

Answer 65

66) A

The characteristic way in which atoms of an element react is most related to the number of
valence electrons in the outermost shell.

Question 66

67

Answer 66

67) D

The answer choice “Solid water contains more dissolved oxygen than liquid water” is false. The
state of water, liquid or solid, does not affect the concentration of oxygen dissolved in it.

Question 67

68

Answer 67

68) C

A coastal climate is moderated primarily because water has a high heat of evaporation.

Question 68

69

Answer 68

69) D

Human blood has a pH of about 7.4. This is slightly basic.

Question 69

70

Answer 69

70) C

Question 70

71

Answer 70

71) D

Since water is a polar molecule and has charges, it is attracted to other substances with charges.
Nonpolar substances do not have charges and therefore do not attract water.

Question 71

72

Answer 71

72) C

A solution with a pH of 7.0 has times more than a solution of pH 10.

Question 72

73

Answer 72

73) C

A solution with a pH of 6.0 has times less than a solution of pH 10.

Question 73

74

Answer 73

74) A

If hydrogen ions are added to blood, bicarbonate ions would combine with the acid forming carbonic acid.

Question 74

75

Answer 74

75) A

Question 75

76

Answer 75

76) A

The first valence shell will hold a maximum of two electrons.

Question 76

77

Answer 76

77) A

The first valence shell will have two electrons which will leave the remaining six to go in the
second valence ring.

Question 77

78

Answer 77

78) A

A molecule that is formed with two or more of the same type of atom are bonded together.

Question 78

79

Answer 78

C

Triple covalent bonds are the strongest covalent bond.

Question 79

80

Answer 79

80) B

Cohesion is the attraction of a water molecule to another water molecule.

Question 80

81

Answer 80

81) A

Baking soda, oven cleaner, and human blood are all basic substances.

Question 81

82

Answer 81

82) A

The frozen form of water is NOT more dense than the liquid form.

Question 82

83

Answer 82

83) A

Because water molecules have charges, they like to stick to other things with charges such as
glass. Adhesion describes the attraction of water molecules to other charged substances.

Question 83

84

Answer 83

84) A

The mass number is the sum of the number of protons and neutrons in an element.

Question 84

85

Answer 84

85) D

The number of carbon atoms in the fatty acid chain is not something that differs between
saturated and unsaturated fatty acids.

Question 85

86

Answer 85

86) B

Cellulose is not used primarily for energy storage. It is a structural carbohydrate used by plants
in the formation of their cell walls.

Question 86

87

Answer 86

87) A

The lipids of the cell membrane and the lipids found in butter and vegetable oil differ in the
number of fatty acids. Phospholipids, which are found in the cell membrane, have two fatty acids
while triglycerides, found in butter and vegetable oils, have three fatty acids.

Question 87

88

Answer 87

88) A

When hydroxyl groups are attached to a hydrocarbon, the molecule becomes an alcohol.

Question 88

89

Answer 88

89) D

The primary function of carbohydrates is immediate energy. Fats provide insulation and
protection, DNA stores hereditary information, and phospholipids form the structural framework
of all cell membranes.

Question 89

90

Answer 89

B

Since the chemical test identified the presence of peptide bonds, your solution contains protein.
Protein consists of amino acids linked together with peptide bonds.

Question 90

91

Answer 90

91) B

Hydrogen bonds are necessary for a polypeptide to move from primary structure to secondary
structure. The hydrogen bonds transition the molecule from a linear form to either an alpha helix
or beta sheet formation.

Question 91

92

Answer 91

92) C

Organic molecules are those that contain at least carbon and hydrogen.

Question 92

93

Answer 92

93) B

Question 93

94

Answer 93

94) C

A hydrocarbon is hydrophobic except when it has a polar functional group attached. The polar
functional group adds charges to the molecule which makes it attractive to water (hydrophilic).

Question 94

95

Answer 94

95) B

Molecules that have identical molecular formulas but different molecular configurations are
isomers.

Question 95

96

Answer 95

96) E

The molecule pictured is cholesterol which is a steroid and all steroid molecules have skeletons
of four fused carbon rings.

Question 96

97

Answer 96

C

is the molecular formula for five glucose molecules. Each glucose molecule is
and when multiplied by five equals. . To connect the five glucose molecules, there are
four bonds formed through dehydration synthesis. One water is removed with the formation
of each bond which equals . Subtract from and you are left with .

Question 97

98

Answer 97

98) A

A polysaccharide is a polymer made of monomers of simple sugars which are also known as
monosaccharides.

Question 98

99

Answer 98

99) E

A triglyceride is made of three fatty acids and glycerol.

Question 99

100

Answer 99

100) A

A dehydration reaction can also be called a condensation reaction since it forms water.

Question 100

101

Answer 100

D

Cellulose and chitin are structural carbohydrate molecules.

Question 101

102

Answer 101

102) C

Cellulose is the carbohydrate found in the cell walls of plants.

Question 102

103

Answer 102

103) D

Glycogen is used to store energy in the liver.

Question 103

104

Answer 103

104) B

Chitin is found in the exoskeleton of insects and crabs.

Question 104

105

Answer 104

105) C

This molecule is a carbohydrate. It may easily be identified by confirming the C:H:O ratio as
1:2:1.

Question 105

106

Answer 105

106) B

If an animal needed to store energy for long-term use, the best choice would be fat molecules.

Question 106

107

Answer 106

107) D

A peptide bond is found in protein molecules.

Question 107

108

Answer 107

108) B

Secondary structure of a protein consists of either an alpha helix or a beta pleated sheet.

Question 108

109

Answer 108

109) A

At the molecular level in different organisms, enzymes determine the optimal temperature and
pH range for a cell.

Question 109

110

Answer 109

110) D

Incorrect Answers: DNA is the genetic material of the cell. DNA, a double helix, consists of a
backbone of repeating phosphate and sugar molecules. The sugar in DNA is specifically
deoxyribose (ribose is found in RNA). The complementary base pairs that populate the central
portion of the DNA molecule are A-T, C-G

Question 110

111

Answer 110

A

DNA contains high amounts of nitrogenous bases, sugar, and phosphate groups.

Question 111

112

Answer 111

112) B

In RNA, one of the bases from DNA (thymine) is replaced by uracil.

Question 112

113

Answer 112

113) B

The reactivity of an organic molecule is primarily dependent on the attached functional group of
the molecule.

Question 113

114

Answer 113

114) B

Unsaturated fatty acids have double bonds between some of the carbon atoms.

Question 114

115

Answer 114

115) D

A saturated fat is often solid at room temperature, has fatty acids with no double bonds between
the carbon atoms, and is of animal origin. It does not contain more fatty acids chains than an
unsaturated fat.

Question 115

116

Answer 115

116) D

Question 116

117

Answer 116

117) B

Five molecules of water are used in hydrolysis reactions to degrade this polypeptide. One water
molecule for each broken bond.

Question 117

118

Answer 117

118) A

Figure 2 depicts a polymer undergoing hydrolysis. During hydrolysis a covalent bond is broken
when a water molecule is added.

Question 118

119

Answer 118

119) D

If 15% of the bases are adenine, then 15% would be thymine (since they are complementary
bases). This means the remaining 70% would be divided between cytosine and guanine.

Question 119

120

Answer 119

120) A

Sulfhydryl is represented by the letters SH

Question 120

121

Answer 120

A

Steroids function as sex hormones and as a component of the cell membrane (cholesterol).

Question 121

122

Answer 121

122) A

The best source of unsaturated fats would be the olive oil or safflower oil. Both of these are plant
oils.

Question 122

123

Answer 122

123) E

Proteins function in all of the following except for storage of energy.

Question 122

124

Answer 122

124) A

Hemoglobin is found within the red blood cells. Keratin is found in hair and nails, and collagen
is found within the ligaments, tendons, and skin. Actin and myosin are found within the muscles.

Question 123

125

Answer 123

A

A tertiary protein structure consists of a single polypeptide chain folded into a globular shape.

Question 123

126

Answer 123

126) A

A pentose sugar, phosphate, and nitrogen-containing base are the components that make up a
nucleotide.

Question 124

127

Answer 124

127) B

RNA is a nucleic acid. Myosin is a protein, glucose and glycerol are carbohydrates, and cytosine
is a nitrogenous base.

Question 125

128

Answer 125

128) D

ATP has three phosphate bonds. The last two bonds are unstable and easily broken which
releases the stored energy.

Question 126

129

Answer 126

129) D

A carbon bond can form four single covalent bonds with other atoms.

Question 127

130

Answer 127

130) D

Waxes consist of long-chain fatty acids bonded with carbon chains containing alcohol functional
groups.

Question 128

131

Answer 128

131) A

ATP is considered a nucleotide because it contains a 5 carbon sugar, a nitrogenous base, and a
phosphate group.

Question 129

132

Answer 129

132) D

Starch is a form of energy storage in plant cells.

Question 130

133

Answer 130

133) A

Migratory birds store energy as fat, since gram per gram, fat stores more energy than glycogen