Deck 4: Nucleic Acids and the Origin of Life

Question 1

A nucleotide in DNA is made up of

A) four bases.
B) a base plus a ribose sugar.
C) a base plus a deoxyribose sugar plus phosphate.
D) a sugar plus a phosphate.
E) a sugar and a base.

Answer 1

C

Question 2

The difference between nucleosides and nucleotides is

A) only nucleotides have nitrogenous bases.
B) a phosphate groups is found in nucleotides but not in nucleosides.
C) nucleotides have the pentose sugar ribose while nucleosides have the pentose sugar deoxyribose.
D) in nucleosides the monomers are joined by phosphodiester bonds; in nucleotides the monomers are joined by hydrogen bonds.
E) nucleosides are the monomers of DNA; nucleotides are the monomers of RNA.

Answer 2

B

Question 3

Which of the following is not a difference between DNA and RNA?

A) DNA has thymine, whereas RNA has uracil.
B) DNA usually has two polynucleotide strands, whereas RNA usually has one strand.
C) DNA has deoxyribose sugar, whereas RNA has ribose sugar.
D) DNA is a polymer, whereas RNA is a monomer.
E) In DNA, A pairs with T, whereas in RNA, A pairs with U.

Answer 3

D

Question 4

Which is a difference between DNA and RNA?

A) DNA is single-stranded and RNA is double-stranded.
B) DNA is only informational and RNA is only catalytic.
C) DNA contains deoxyribose and RNA contains ribose.
D) DNA is transcribed and RNA is replicated.
E) DNA contains uracil (U) and RNA contains thymine (T).

Question 5

The "backbone" of a nucleic acid molecule is made of

A) nitrogenous bases.
B) alternating sugars and phosphate groups.
C) purines.
D) pyrimidines.
E) nucleosides.

Question 6

A nucleotide contains a pentose sugar, a phosphate group, and

A) a lipid.
B) an acid.
C) a nitrogen-containing base.
D) an amino acid.
E) a glycerol.

Question 7

Nucleotides in RNA are connected to one another in the polynucleotide chain by

A) covalent bonds between bases.
B) covalent bonds between sugars.
C) covalent bonds between sugar and phosphate.
D) hydrogen bonds between purines.
E) hydrogen bonds between any bases.

Question 8

All of the major building blocks of macromolecules were made in Miller-Urey prebiotic synthesis experiments except

A) amino acids.
B) hexose sugars.
C) bases for nucleotides.
D) fatty acids.
E) ribose.

Question 9

Findings in ancient rocks indicate cells first appeared

A) about 4.5 billion years ago.
B) about 3.5 billion years ago.
C) about 2 billion years ago.
D) before rocks were formed.
E) before water arrived on Earth.

Question 10

Spontaneous generation of life from nonliving materials

A) can occur in dark places.
B) has not been a belief of humans.
C) has never occurred.
D) requires only nucleotides and fatty acids.
E) was disproven for microorganisms by Pasteur's experiment.

Question 11

Ribose and deoxyribose are both found in nucleic acids. The difference between ribose and deoxyribose is that

A) deoxyribose has one less oxygen molecule than ribose has.
B) ribose is a pentose sugar, whereas deoxyribose is a hexose sugar.
C) deoxyribose is found in DNA, whereas ribose is found in RNA.
D) Both a and b
E) Both a and c

Question 12

What is attached to the 5´-carbon of deoxyribose in DNA?

A) Adenine
B) Phosphate
C) Guanine
D) Thymine
E) Hydrogen

Question 13

Ribozymes are

A) enzymes that are made up of ribose sugar.
B) ancient catalysts that no longer exist.
C) RNA catalysts.
D) present in bacterial cells only.
E) less active than protein enzymes.

Question 14

According to the principle of complementary base pairing, purines always pair with

A) deoxyribose sugars.
B) uracil.
C) pyrimidines.
D) adenine.
E) guanine.

Question 15

The "RNA world" hypothesis proposes that

A) RNA formed from DNA.
B) RNA was both a catalyst and genetic material.
C) RNA was a catalyst only.
D) RNA formed after proteins.
E) DNA formed after RNA was broken down.

Question 16

The components in the atmosphere for the Miller-Urey experiment on prebiotic synthesis did not include

A) H₂.
B) H₂O.
C) O₂.
D) NH₃.
E) CH₄.

Question 17

Examination of ice from Mars suggests that

A) life may not be limited to Earth.
B) life originated in outer space from nonliving matter.
C) comets brought Earth most of its water.
D) meteorites brought life to Earth.
E) meteorites are responsible for Earth's magnetic field.

Question 18

Examination of ice found on Mars has revealed that it contains some of the elements needed for life. Which of the following has not been found in the ice?

A) Potassium ions
B) Magnesium ions
C) Glucose
D) Sodium ions
E) Chlorine ions

Question 19

The bases of nucleic acids are purines or pyrimidines. Purines and pyrimidines are distinguished by the fact that

A) purines include the bases of cytosine and thymine; pyrimidines include the bases of adenine and guanine.
B) pyrimidines are found in RNA; purines are found in DNA.
C) purines consist of hydrogen, carbon, oxygen, and nitrogen, whereas pyrimidines have phosphorus, hydrogen, carbon, oxygen, and nitrogen.
D) purines only have single bonds in their structure, whereas pyrimidines have both single and double bonds in their structure.
E) purines are double-ring structures, whereas pyrimidines are single-ring structures.

Question 20

The nucleotide sequence of DNA

A) is the same in all organisms of a species.
B) contains only information for translation.
C) evolved before RNA.
D) contains the four bases, A, T, G, and C.
E) is produced by prebiotic chemistry experiments.

Question 21

What is the nucleotide sequence of the complementary strand of the DNA molecule: A A T G C G A?

A) T T A C G C T
B) A A T G C G A
C) G G C A T A G
D) C C G T T A T
E) A G C G T A A

Question 22

Which of the following is true?

A) DNA is completely replicated but only partially transcribed.
B) DNA is partially replicated but completely transcribed.
C) Transcription is activated at different times in different cells of the body.
D) Both a and c are true.
E) Both b and c are true.

Question 23

What type of bond connects two complementary nucleotides together?

A) Hydrogen
B) Ionic
C) Peptide
D) Phosphodiester
E) Covalent

Question 24

Complementary base pairing is due to the

A) geometry of the sugar-phosphate backbone.
B) pairing of a purine with a pyrimidine.
C) hydrogen bonding sites.
D) Both a and b
E) All of the above

Question 25

Single-stranded RNA can fold on itself, creating three-dimensional structures such as tRNA. The folds are stabilized by _______ bonds.

A) hydrogen
B) ionic
C) phosphodiester
D) peptide
E) glycosidic

Question 26

DNA carries genetic information in its

A) helical form.
B) sequence of bases.
C) tertiary sequence.
D) sequence of amino acids.
E) phosphate groups.

Question 27

Which of the following is not a nucleotide?

A) Guanosine triphosphate
B) Cyclic adenosine monophosphate
C) An amino acid
D) Adenosine triphospate
E) Ribonucleic acid

Question 28

In 1668, Francesco Redi did some experiments to disprove spontaneous generation. He began by putting pieces of meat into identical jars. Some jars were left open to the air, and some were sealed. He then did the same experiment with one variation: instead of sealing the jars completely, he covered them with gauze (which kept out flies while allowing the meat to be exposed to the air). In both experiments, he checked if fly maggots appeared in the meat or not. What hypothesis was being tested?

A) Spontaneous generation is more likely to occur during the hot days of summer.
B) Maggots do not arise spontaneously but from eggs laid by adult flies.
C) The type of meat affects whether spontaneous generation occurs.
D) Spontaneous generation can occur only if air is present.
E) Flies will develop from rotting meat if the meat is exposed to air.

Question 29

The diversity in DNA molecules is due to

A) physical shape differences of the molecule.
B) functional differences in DNA molecules.
C) base sequence differences in the DNA molecule.
D) hydrogen bonding differences found in the DNA molecule.
E) complementary base pairing differences in DNA molecules.

Question 30

The central dogma of molecular biology states that

A) the genetic code is ambiguous.
B) the information flow between DNA, RNA, and a protein is reversible.
C) the information flow in a cell is from DNA to RNA to protein.
D) the information flow in a cell is from protein to RNA to DNA.
E) the information flow in a cell is from DNA to a protein to RNA.

Question 31

The four nitrogenous bases of RNA are abbreviated as

A) A, G, C, and T.
B) A, G, T, and N.
C) G, C, U, and N.
D) A, G, U, and T.
E) A, G, C, and U.

Question 32

In DNA, A pairs with T, and C pairs with G; these are examples of a specific type of reaction called

A) complementary base pairing.
B) a dehydration reaction.
C) a reduction reaction.
D) a hydrophobic reaction.
E) a purine-purine reaction.

Question 33

Consider the following double-stranded DNA region:
TGCCAT
ACGGTA
If the lower strand is transcribed, which of the following strands will result?

A) TGCCAT
B) TCGGTA
C) UGCCAU
D) UGCCUA
E) TCGGUT

Question 34

Which of the following depend on complementary base pairing?

A) DNA replication
B) Transcription
C) Translation
D) Both a and b
E) All of the above

Question 35

What accounts for the stability of the DNA molecule?

A) The bonds between purines and pyrimidines
B) Phosphodiester bonds between the nitrogenous bases
C) Strong hydrogen bonds between the sugar and phosphate groups
D) Its double-helix shape
E) The direct bonding of the base to the phosphate molecule

Question 36

The double-helix structure of DNA is the result of

A) complementary base pairings.
B) purines bonding with pyrimidines.
C) the phosphodiester bonds between deoxyribose and phosphate.
D) hydrogen bonding of the two complementary polynucleotide strands.
E) ionic bonding of base pairs.

Question 37

A prerequisite for life on Earth or any other planet is

A) sunlight.
B) water.
C) amino acids.
D) nitrogen.
E) carbon dioxide.

Question 38

Complementary base pairing can be explained by

A) the relative sizes of purines and pyrimidines.
B) the alternating sugar-phosphate groups.
C) an examination of evolutionary relationships.
D) the differences found in RNA and DNA.
E) the diversity found in proteins.

Question 39

All of the following bases are found in DNA except

A) thymine.
B) adenine.
C) uracil.
D) guanine.
E) cytosine

Question 40

DNA differs from RNA in that

A) RNA contains uracil instead of thymine.
B) RNA is single stranded; DNA is double stranded.
C) RNA leaves the nucleus: DNA does not.
D) RNA contains ribose; DNA contains deoxyribose.
E) All of the above

Question 41

RNA molecules that act as catalysts are called

A) ribozymes.
B) glycosidic linkages.
C) chaperonins.
D) disulfide bridges.
E) triglycerides.

Question 42

Which of the following statements about protocells is false?

A) They can act as a system of interacting parts.
B) Their interiors are separated from their exteriors.
C) They are amphipathic.
D) They are able to replicate nucleic acids.
E) They can perform normal cellular metabolic reactions.

Question 43

The Miller-Urey experiment showed that in any environment with conditions similar to those of Earth,

A) inorganic molecules would react to form organic molecules.
B) RNA would self-replicate.
C) organic molecules would form primitive cells.
D) an oxygen atmosphere would develop.
E) DNA would be synthesized.

Question 44

What is the evidence supporting the claim that ancient rocks contain the fossils of cells?

A) The imprints of chloroplasts can be seen in the rocks.
B) Radioactive tracing of CO₂ in the rocks shows similarities to modern cells.
C) Microscopic examination of the rocks shows chains of cells that are similar to modern cyanobacteria.
D) DNA analysis of the rocks shows similarities to modern cells.
E) Pieces of RNA found in the rocks are similar to ribozymes.

Question 45

Which of the following was a limitation of the Miller-Urey experiment in the 1950s?

A) The experiment synthesized both D- and L-isomers of amino acids, but the amino acids in living things are always L-isomers.
B) The experimenters assumed that Earth's early atmosphere contained only hydrogen gas, methane, ammonia, and water vapor; however, evidence uncovered more recently suggests that Earth's early atmosphere contained many more components.
C) DNA is not self-catalytic.
D) In living organisms today, peptide linkages are catalyzed by ribozymes.
E) The hot temperatures of the experiments denatured some of the proteins that were synthesized.

Question 46

Purines have a _______-ring structure; pyrimidines have a _______ ring.

Question 47

Adenine and guanine are classified as _______.

Question 48

The Miller-Urey experiment demonstrated that

A) under specific conditions, the building blocks of life can be formed.
B) life on Earth came from other bodies in the solar system.
C) CO₂, N₂, H₂S, and SO₂ were probably present in Earth's early atmosphere.
D) volcanic eruptions may have released CO₂, N₂, H₂S, and SO₂ into Earth's early atmosphere.
E) ice has been found in meteorites and on Mars.

Question 49

Which of the following was not a component of Earth's early atmosphere?

A) Hydrogen gas
B) Ammonia
C) Water vapor
D) Oxygen
E) Methane gas

Question 50

Which of the following supports the "replicator first" theory?

A) The role of RNA as genetic material and as a catalyst
B) Evidence of the early emergence on Earth of chemical reactions that resulted in monomers
C) Evidence of the nearly spontaneous formation of lipid micelles on Earth
D) Evidence of the prebiotic chemical generation of cell-like compartments
E) The chemical traces of life found on meteorites

Question 51

Molecules consisting only of a pentose sugar and a nitrogenous base are called _______.

Question 52

Which evidence supports the argument that life may have come from outside Earth?

A) Reorientation studies indicate that long interplanetary trips by living organisms is possible.
B) Macromolecules unique to life have been found in meteorites.
C) Polycyclic aromatic hydrocarbons have been found in meteorites.
D) Magnetite, an iron oxide mineral made by many living organisms on Earth has been found in meteorites.
E) All of the above

Question 53

Spontaneous generation was finally disproved by

A) Stanley Miller.
B) Harold Urey.
C) Francesco Redi and Louis Pasteur.
D) Allan Hills.
E) Johannes van der Waals.

Question 54

Which of the following was not synthesized by the Miller-Urey experiment?

A) Most of the amino acids used in protein synthesis
B) Small carbon sugars
C) Adenine and thymine
D) Ribose
E) Uracil

Question 55

The "metabolism first" theory proposes that evolution first took place

A) in RNA, which acted as both genetic material and a catalyst.
B) as chemical reactions that resulted in monomers.
C) in lipids.
D) in the trace elements.
E) in proteins.

Question 56

The difference between nucleotides and nucleosides is a(n) _______.

Question 57

Examination of meteorites has revealed that they contain the chemistry of life. All of the following have been found in meteorites except

A) purines and pyrimidines.
B) amino acids.
C) glucose.
D) magnetite.
E) polycyclic aromatic hydrocarbons.

Question 58

Examination of meteorites suggests that

A) life is not limited to Earth.
B) life originated in outer space from nonliving matter.
C) comets brought Earth most of its water.
D) meteorites brought life to Earth.
E) meteorites are responsible for Earth's magnetic field.

Question 59

Life on Earth arose approximately _______ years ago.

A) 6.4 billion
B) 4 billion
C) 600 million
D) 2,000
E) 2 million

Question 60

Which of the following is a plausible explanation for the presence of carbon dioxide in Earth's early atmosphere?

A) Volcanic eruptions could have released carbon dioxide into the atmosphere.
B) Cyanbacteria were present on Earth 3.5 billion years ago.
C) Retroviruses catalyzed the formation of carbon dioxide.
D) Geysers may have produced the Earth's early environment.
E) Chemical reactions with water resulted in the formation of carbon dioxide.

Question 61

The pairing of purines with pyrimidines to create a double-stranded DNA molecule is called

A) complementary base pairing.
B) phosphodiester linkages.
C) antiparallel synthesis.
D) dehydration.
E) the genome.

Question 62

The process by which a RNA nucleotide sequence can specify a sequence of amino acids in a polypeptide is called _______.

Question 63

The term used to describe molecules that have both hydrophilic and hydrophobic properties is _______.

Question 64

It took about 600 million years for life on Earth to develop. This geologic time frame is known as the _______.

Question 65

Astronomers believed the solar system began forming 4.6 billion years ago, when a star exploded to form bodies called _______.

Question 66

Evidence to support that life may have come from outside Earth includes the presence of simple carbon- containing molecules called _______ in meteorites.

Question 67

The process by which DNA makes an exact copy of itself is called _______.

Question 68

The end product of transcription is _______ and the end product of translation is _______.

A) proteins; DNA
B) proteins; RNA
C) RNA; DNA
D) DNA; RNA
E) RNA; proteins

Question 69

The experiment depicted in the diagram below proves that

A) amino acids are the building blocks of life.
B) some forms of life can arise by spontaneous generation.
C) oxygen is needed for life.
D) life comes from decaying matter.
E) life comes from preexisting life.

Question 70

_______ is the theory that life's simple molecules formed in Earth's primitive environment.

Question 71

Closely related living species should have _______ (more/less) similar base sequences than species that are more distantly related.

Question 72

A laboratory model of a prebiotic structure that resembles modern cells is called a _______.

Question 73

Life from inanimate matter is referred to as _______.

Question 74

The process by which DNA makes an RNA transcript of itself is called _______.

Question 75

The sequences of DNA that encode specific proteins and are transcribed into RNA are called _______.

Question 76

Some RNA molecules can act as catalysts. Catalytic RNA, or _______, can catalyze reactions on their nucleotides.

Question 77

The complete set of DNA in a living organism is called its _______.

Question 78

Redi worked with _______ to disprove the idea of spontaneous generation.

Question 79

According to the principle of complementary base pairing, in RNA, adenine always bonds with _______.

Question 80

The diversity found among DNA molecules is due to the sequence of _______.