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Flashcards in Exam 4 Review Deck (149)
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1
Q

What is a hypothesis?

A

A tentative explanation that can be tested by experiments.

2
Q

What is the process of science?

A

Observation, question, hypothesis formulation, experiment, support or refute hypothesis

3
Q

Which of the following is not associated with living things? 1. ability to harvest energy 2. ability to respond to surroundings 3. ability to maintain its internal environment 4. storage of genetic information in proteins 5. ability to reproduce

A

storage of genetic information in proteins

4
Q

What are the 4 most abundant chemical elements in a cell?

A

carbon, oxygen, hydrogen, nitrogen

5
Q

What are the four major groups of macromolecules?

A

Proteins, complex carbohydrates, nucleic acids, lipids

6
Q

A single covalent bond represents the sharing of how many electrons?

A

2

7
Q

The versatility of the carbon atom and the reason it is said to be the “backbone of life” is due to the fact that carbon atoms….

A

have four unpaired electrons in their outer shell

8
Q

How many hydrogen atoms are present in a hydrocarbon chain of 10 carbon atoms that are held together by 5 single covalent bonds and four double covalent bonds?

A

14

9
Q

The unique properties of water are due to the _____ of water molecules and the abiliyt of water to form _____ with other water molecules and with other polar particles.

A

polarity/hydrogen bonds

10
Q

Cellulose is made by _____ cells and functions as _______ molecule.

A

plant/structural

11
Q

What bond is associated with the formation of complex carbohydrates?

A

glycosidic linkage

12
Q

What bond is associated with the formation of Triglycerides?

A

ester bonds

13
Q

What bond is associated with the formation of proteins?

A

peptide bonds

14
Q

The bonds that hold monomers together in polymers are always?

A

covalent bonds

15
Q

Condensation reactions (also called dehydration reactions) are involved in?

A

the synthesis of a complex carbohydrate and the synthesis of a protein

16
Q

Of the three subatomic particles that make up atoms, only ____ are directly involved in the formation of chemical bonds?

A

electrons

17
Q

Chemical bonds that rely on the attraction of positive and negative charges are ______?

A

ionic bonds and hydrogen bonds

18
Q

T/F: on the pH scale, a value of 1 is highly acidic, 14 is highly basic, and 7 is neutral.

A

T

19
Q

T/F: the higher the concentration of hydrogen ions, the higher the pH.

A

F

20
Q

T/F: in a polar covalent bond between two atoms, the shared electrons spend more time around the nucleus of one of the atoms than the other.

A

T

21
Q

T/F: Ionic bonds are relatively strong in the presence of water.

A

F

22
Q

T/F: electrons located in orbitals close to the nucleus of an atom have less potential energy than the electrons located in orbitals farther away from the nucleus.

A

T

23
Q

A solution with a pH of 4.0 has _________ hydrogen ions as a solution with a pH of 2.0.

A

100 times less

24
Q

Which functional groups are nonpolar?

A

CH3

25
Q

Which functional group is an amino group?

A

NH2

26
Q

Which functional groups are found in all amino acids?

A

NH2 & C=O-OH

27
Q

What is the 3-D conformation assumed by a polypeptide chain?

A

Tertiary structure

28
Q

The association of two or more polypeptide subunits to make a functional protein.

A

Quaternary structure

29
Q

Identify this structure:

A

Amino Acid

30
Q

Identify this structure:

A

triglyceride

31
Q

Identify this structure:

A

cholesterol (has a hydrophilc and hydrophobic end)

32
Q

A prediction is?

A

an if-then statement

33
Q

The dependent variable in an experiment is:

A

the stuff being measured

34
Q

The independant variable in an experiment is:

A

the stuff being altered

35
Q

A polar covalent bond is:

A

an unequal sharing of a pair of electrons by two atoms

36
Q

T/F: The assembly of complex carbohydrates and proteins depends on condensation reactions.

A

T

37
Q

T/F: The breakdown of some macromolecules depends on condensation reactions.

A

F

38
Q

T/F: Condensation reactions use a molecule of water to separate a monomer from a polymer chain.

A

F

39
Q

What kind of bonds hold the hydrogen atoms to the oxygen atom in a moleule of water?

A

polar covalent bonds

40
Q

How many hydrogen atoms are present in a hydrocarbon chain of 8 carbons held together by 6 single covalent bonds and 1 double covalent bond?

A

16

41
Q

A solution with a pH of 6 has _____ hydrogen ions as a solution with a pH of 3.

A

1000 times fewer

42
Q

The lipid components of cellular membranes include ______

A

phospholipids and cholesterol

43
Q

Integral membrane proteins are proteins that:

A

partially penetrate or completely span the phospholipid bilayer of the membrane.

44
Q

Cells engulf particles and bring them into the cytoplasm using a process called _____

A

endocytosis

45
Q

The movement of ions and other charged or large, polar molecules across biological membranes is made possible by _______

A

the integral membrane proteins present in the membrane.

46
Q

What do gap junctions and desmosomes have in common with each other?

A

They both depend on the function of integral membrane proteins.

47
Q

Identify this structure:

A

gap junction

48
Q

Identify this structure:

A

tight junction

49
Q

Identify this structure:

A

desmosome

50
Q

The unregulated movement of ions and large polar molecules across membranes is prevented by:

A

the hydrophobic core of the lipid bilayer

51
Q

T/F: the rate of diffusion increases as temperature increases

A

T

52
Q

T/F: Diffusion occurs whether or not a concentration gradient is present.

A

T

53
Q

T/F: The rate of diffusion of a molecule depends on the kinetic energy of the molecule.

A

T

54
Q

T/F: Diffusion refers to the tendency of molecules to move about randomly in space.

A

T

55
Q

T/F: Net diffusion refers to the directional movement of molecules from an area of high concentration to one of lower concentration.

A

T

56
Q

T/F: Net diffusion continues once a solution is at equilibrium.

A

F

57
Q

T/F: Diffusion stops once a solution is at equilibrium.

A

F

58
Q

Movement of substances across a membrane by active transport require what?

A

ATP and integral membrane proteins

59
Q

A fatty acid with no double bonds between carbon atoms is _____ and has _______ hydrogen atoms bonded to the carbon atom.

A

saturated, the max number

60
Q

The fluidity of cellular membranes is influenced by several factors including (3)

A

temperature, saturation of fatty acid side chains, and cholesterol

61
Q

As the number of double bonds present in the fatty acide side chains of phospholipids increases, the fluidity of the membrane:

A

increases

62
Q

Metabolic pathways that make simple molecules from complex ones are

A

catabolic

63
Q

The types of reactions that take place in the pathways described in the question above are usually classified as ____ reactions because of their tendency to release energy.

A

Exergonic or spontaneous.

64
Q

G=H-TS is the equation that describes Gibbs free energy. Rearranged, the equation can be written as H = G+TS. In either case, G stands for _____, H stands for ______, and S stands for ______.

A

usable (free) energy, total (enthalpy) energy, unavailable (entropy) energy

65
Q

T/F Metabolic pathways always release energy stored in organic compounds

A

F

66
Q

T/F: The product of one reaction becomes the substrate for the next reaction in a metabolic pathway.

A

T

67
Q

T/F: Metabolic pathways are a series of enzyme catalyzed reactions.

A

T.

68
Q

T/F: Metabolic pathways are similar in all organisms

A

T

69
Q

T/F: Metabolic pathways are often compartmentalized in eukaryotic cells

A

T

70
Q

Why do slight changes in pH dramatically decrease enzyme activity?

A

The hydrogen ions and ionic interactions that stabilize the conformation of the enzyme are disrupted.

71
Q

What is a characteristic of the transmembrane protein of the protein (the part that resides in the phospholipid bilayer)

A

many of the amino acid side chains of the transmembrane domain are hydrophobic

72
Q

The initial “investment” of energy required for a chemical reaction to proceed is called the:

A

activation energy

73
Q

T/F: Enzyme substrates are guided into the active site by chaperone proteins

A

F

74
Q

T/F: the supply of enzymes in a reaction is used up at the same rate as the other reactants.

A

F

75
Q

T/F The active site of an enzyme is determined by the primary, secondary, and tertiary structure of the protein.

A

T

76
Q

T/F: Enzymes with more than one polypeptide unit do not act as catalysts.

A

F

77
Q

Some bacteria are metabolically active in hot springs because:

A

their enzymes have high optimal temperatures

78
Q

The denaturation of an enzyme ocurs when: (3)

A
  1. the active site is destroyed
  2. the tertiary structure of the enzyme is altered
  3. environmental conditions deviate substantially from the enzymatic optimum conditions
79
Q

Noncompetitive inhibition of enzyme activity is:

A

an example of allosteric regulation

80
Q

Briefly describe the relationship between cellular respiration and photosynthesis.

A

photosynthesis stores energy in organic molecules and respiration releases it

81
Q

The minimum requirements of photosynthesis are: (3)

A

light, CO2, H2O

82
Q

Which of the steps of photosynthesis would be affected first by a lack of solar energy?

A

oxidation of chlorophyll

83
Q

T/F: the electron transport chain in the cholorplasts of plant cells pumps hydrogen ions from the stroma into the thylakoid.

A

T

84
Q

What happens to the stoma of chloroplasts in outdoor plants as the daylight fades into night?

A

the pH of the stroma decreases and becomes more acidic (aka the hydrogen ion concentration goes up)

85
Q

What macromolecule is wood primarily made of?

A

carbohydrate

86
Q

Where does the carbon in wood originally come from?

A

the air

87
Q

Where did the energy released from a burning log originate?

A

Solar energy

88
Q

Plasma membranes are found in:

A

animal, plant, and bacterial cells.

89
Q
A
90
Q

What outputs of photosynthesis are inputs of cellular respiration?

A

oxygen, carbon dioxide

91
Q

T/F: The activity of DNA polymerase is higher in S phase of the cell cycle than it is in G1.

A

T

92
Q

T/F: Each sister chromatid in a replicated chromosome is a double-stranded DNA molecule

A

T

93
Q

T/F: A cell in G2 of the cell cycle has twice as many chromosomes as it had in G1

A

T

94
Q

T/F: Following anaphase, a cell has half as much DNA as it did when it was in prophase.

A

F

95
Q

T/F: A chromosome in G1 of the cell cycle is one double-stranded DNA molecule.

A

T

96
Q

In plant cells, glycolysis takes place in the ______.

A

Cytoplasm

97
Q

When a cell harvests energy stored in a molecule of glucose, it does so by _____.

A

removing electrons

98
Q

When a cell metabolizes a glucose molecule, most of the energy is harvested in the ____

A

citric acid cycle

99
Q

When oxygen is present, the pH in the matrix of the mitochondria should be _____ compared to the intermembrane space due to the _______ concentration of hydrogen ions in the intermembrane space.

A

higher/higher concentration

100
Q

Identify this structure:

A

pyrimidine nucleotide

101
Q

Identify this structure:

A

purine nucleotide

102
Q

Most actively dividin cells in the body undergo mitotic division. The cell cycle in these cells is divided into two main parts which are ______ and _______

A

interphase and M phase (or mitotic phase)

103
Q

Photosynthesis _______ energy while cellular respiration ________ energy.

A

stores (in organic molecules) , releases

104
Q

What is the function of NADPH, NADH, and FADH2 in photosynthesis and respiration?

A

they transport high-energy electrons to an electron transport chain.

105
Q

In the eukaryotic cells, complexes I, III, and IV are important components of the mitochondrial electron transport chain because during their reduction/oxidation cycles they pump _______ from the _______ to the _______.

A

hydrogen ions, matrix, intermembrane space

106
Q

When oxygen is present and the citric acid cycle is active, the pH of the mitochondrial matrix is _____ than the intermembrane space because of the ________ concentration of hydrogen ions in the matrix.

A

higher (more basic), lower

107
Q
A
108
Q

The hydrogen ion gradient across the thylakoid membrane is required to _____

A

power ATP synthase

109
Q

Describe the reducing agent in a redox reaction:

A

the reducing agent gets oxidized, loses an electron

110
Q

In which compartment of the cell does the glucose convert to pyruvate in a redox reaction?

A

the cytoplasm

111
Q

In which part of the cell does glycolysis take place?

A

Cytoplasm

112
Q

In which part of the cell does ATP production by ATP synthase take place?

A

Inner mitochondrial membrane

113
Q

In which part of the cell does the citric acid cycle take place?

A

matrix of the mitochondria

114
Q

The products of glycolysis include (3):

A

ATP, NADH, and pyruvate

115
Q

T/F: As a result of depletion of oxygen in the surrounding of the cell, the cell switches to anaerobic respiration to maintain some level of ATP production.

A

T

116
Q

T/F: As a result of depletion of oxygen in the cell’s surroundings, Glycolysis, the citric acid cycle, and the electron transport chain, and ATP synthase all shut down due to lack of oxygen.

A

F

117
Q

T/F When there is a lack of oxygen, fermentation pathways are activated and produce the same amount of ATP normally produced by glycolysis, the citric acid cycle, and the electron transport chain.

A

F

118
Q

T/F: When oxygen is not present in a cell’s surroundings, cells use fermentation to regenerate the NAD+ needed for glycolysis.

A

T.

119
Q

The mitochondrial electron transport chain is

A

a series of molecules including integral membrane proteins in the inner membrane of the mitochondria

120
Q

The immediate energy source that directly powers ATP synthesis by ATP synthase in mitochondria is _____

A

the H+ gradient across the inner mitochondrial membrane

121
Q

The thylakoid membranes in chloroplasts and the inner membrane of mitochondria are structurally and functionally alike because (2)

A
  1. both provide greatly amplified surface area for ATP production
  2. electron transport chains are found in both of them.
122
Q

What would be most likely to act as an allosteric inhibitor of an enzyme that catalyed a reaction in the early pathway of glycolysis?

NAD+, NADPH, lactic acid, ATP, or oxygen?

A

ATP

123
Q

ATP synthase is (3)?

A
  1. an enzyme
  2. a transport protein
  3. an integral membrane protein.
124
Q

Describe the flow of ELECTRONS through living organisms.

A

water - photosynthesis - carbohydrate - cellular respiration -water

125
Q

The two strands of a double-stranded DNA molecule are held together by ______ between nitrogenous bases and the nucleotides in each strand are held together by ______.

A

hydrogen bonds, covalent bonds

126
Q

In DNA molecules, base pairs always include one purine and one pyrimidine. In the DNA of certain bacterial cells, 16% of the nucleotides are adenine. What are the percentages of the other nucleotides in the bacterial DNA?

A

16% Thymine, 34% Guanine, 34% cytosine

127
Q

When a DNA molecule is heated, the two strands of the double helix become unzipped and come apart because the _____ between base pairs are destabilized.

A

hydrogen bonds

128
Q

Most actively dividing cells in the body undergo mitotic cell division. The cell cycle in these cells is divided into two main parts which are _____ and ______.

A

interphase and M phase

129
Q

All of the following happen during mitosis except:

condensing of the chromosomes

formation of the spindle microtubles

synthesis of DNA

uncoupling of the sister chromatids at the centromeres

A

synthesis of DNA

130
Q

An epithelial cell divides during mitosis to form two genetically identical daughter cells. Prior to the mitotic phase of the cell, what must occur?

the nuclear envelope must disintegrate

the cell must first be fertilized

the nucleus must divide

chromatids must be separated

the cell must replicate its chromosomes

A

the cell must replicate its chromosomes

131
Q

If a cell has defects in the function of its microtubules, which of the following would be most obviously affected?

mitosis

cytokinesis

G1

S phase

G2

A

mitosis

132
Q

The muscle cells and nerve cells in a mouse look very different and serve very different functions in the mouse’s body. These differences are because the muscle cells and nerve cells in the mouse _______

A

express different genes

133
Q

A gene is:

A

a region of DNA that is required for the production of an RNA molecule

134
Q

The process of RNA synthesis by RNA polymerase using the information in a DNA molecule is called :

A

transcription

135
Q

The promoter is a : amino acid or nucleotide/DNA ?

A

nucleotide/DNA

136
Q

RNA polymerase is a: amino acid or nucleotide/DNA ?

A

amino acid

137
Q

A transcription factor is a:amino acid or nucleotide/DNA ?

A

amino acid

138
Q

the Transcription unit is a: amino acid or nucleotide/DNA ?

A

nucleotide/DNA

139
Q

a polypeptide is a : amino acid or nucleotide/DNA ?

A

amino acid

140
Q

the initiator site is a: amino acid or nucleotide/DNA ?

A
141
Q

What describes the alleles of a particular gene if the phenotype of an individual that is heterozygous for that gene resembles neither parent?

A

one of the alleles is incomplete dominant over the other

142
Q

Sister chromatids separate during:

A

meiosis II and mitosis!!!

143
Q

Homologous chromosomes are separated during:

A

meiosis I (cytokinesis I)

144
Q

The number of chromosomes is reduced by 50% during:

A

meiosis I

145
Q

The muscle cell of a certain diploid organism has 12 chromosomes. How many copies of each gene are present in the cell at G1 of the cell cycle?

A

2

146
Q

The muscle cell of a certain diploid organism has 12 chromosomes. How many copies of each gene is present in the cell at G2 of the cell cycle?

A

4

147
Q

The muscle cell of a certain diploid organism has 12 chromosomes. How many molecules of DNA are present in the nucleus at G2?

A

24

148
Q

The muscle cell of a certain diploid organism has 12 chromosomes. How many copies of each gene are present in the gamates of the organism?

A

1

149
Q
A