Deck 15: Genes and How They Work

Question 1

Crick and his colleagues proposed that the genetic code consisted of a series of blocks of information,called _____,each corresponding to an amino acid in the encoded protein.

A)alleles
B)codons
C)DNA
D)polypeptides

Answer 1

B

Question 2

The polypeptide-making organelles residing in the cytoplasm are large protein aggregates to which RNA is associated.They are called

A)ribosomes.
B)Golgi bodies.
C)lysosomes.
D)the endoplasmic reticulum.
E)mitochondria.

Answer 2

A

Question 3

Gene ________ refers to the combined processes of transcription and translation.

A)expression
B)replication
C)modification
D)regulation

Answer 3

A

Question 4

The strand of DNA that is not transcribed is called the ______ strand.

A)coding
B)non-coding
C)replicate
D)inert

Question 5

Most eukaryotic genes contain coding sequences called ________ that are interspersed with noncoding sequences.

A)introns
B)exons
C)codons
D)DNA

Question 6

The connection that exists between genes and hereditary traits requires the deciphering of the information encoded in genes into

A)amino acids.
B)nucleotides.
C)proteins.
D)histone molecules.
E)complementary bases.

Question 7

The "one gene-one enzyme" hypothesis was proposed by

A)Watson and Crick.
B)Griffith.
C)Garrod.
D)Franklin.
E)Beadle and Tatum.

Question 8

Both DNA and RNA are made up of building blocks known as

A)nucleotides.
B)complementary base pairs.
C)amino acids.
D)genes.

Question 9

Amino acids are transported to the ribosome for use in building the polypeptide by

A)mRNA molecules.
B)tRNA molecules.
C)DNA polymerase molecules.
D)rRNA molecules.
E)DNA ligase molecules.

Question 10

The essence of heredity is the ability of cells to use the information in their DNA to bring about the production of particular ________,thereby affecting what the cells will be like.

A)proteins
B)ribosomes
C)RNAs
D)helicases

Question 11

DNA and RNA nucleotides are composed of five carbon sugars,phosphate,and nitrogen bases.How many total nitrogen bases are there for use in the two nucleic acids?

A)2
B)3
C)4
D)5

Question 12

The coded order of nucleotides in a DNA specifies the order of specific amino acids to be assembled into a polypeptide chain.This code is therefore called the ________ code.

A)mitochondrial
B)ribosomal
C)DNA
D)genetic

Question 13

Messenger RNA molecules are copies of DNA;they travel to the ribosomes to direct the assembly of ____________.

A)proteins
B)amino acids
C)polypeptides
D)fatty acids

Question 14

The expression of a gene involves two phases,___________ and translation.

A)replication
B)transcription
C)unwinding
D)condensation

Question 15

Transcription begins at a RNA polymerase-binding site called a _____.

A)ribosome
B)replicator
C)inducer
D)promoter

Question 16

The process in which an RNA polymerase molecule assembles an mRNA molecule whose nucleotide sequence is complementary to the DNA sequence is called

A)gene amplification.
B)translation.
C)transcription.
D)polypeptide sequencing.
E)complementary base pairing.

Question 17

When multiple snRNPs combine to form a larger complex called a ___________ the intron loops out and is excised.

A)synapse
B)introsome
C)exon
D)spliceosome

Question 18

Which of the following is not true about eukaryotic DNA?

A)It is an exceedingly long and fragile molecule.
B)It is packaged into successively compact formations.
C)The entire molecule has encoded information for protein synthesis.
D)In the condensed form,it is transcriptionally inactive.
E)It must be unpackaged before it can be transcribed into RNA.

Question 19

In _________,a ribosome assembles a polypeptide,whose amino acid sequence is specified by the nucleotide sequence in the mRNA (which itself is a copy of the template DNA).

A)transcription
B)translation
C)replication
D)synthesis

Question 20

Following transcription,the intron sequences are cut out of the primary transcript and the ends are joined again prior to its use in protein synthesis.This processing of the RNA is called RNA __________.

A)modification
B)translation
C)splicing
D)transcription

Question 21

Protein synthesis proceeds by the ribosome

A)alternating between many chains.
B)moving three nucleotides at a time on the mRNA.
C)attaching amino acids in a random fashion.
D)selecting the tRNA molecule that fits.
E)attaching amino acids to the growing chain without charged tRNAs.

Question 22

Ribosome movement along the mRNA transcript is called

A)transcription.
B)translation.
C)replication.
D)translocation.
E)mutation.

Question 23

Ribosomes are complex arrangements of

A)RNA and DNA.
B)RNA and large proteins.
C)RNA and sugars.
D)DNA and proteins.
E)nucleosomes and RNA.

Question 24

The 3-nucleotide sequence of an mRNA is called the

A)codon.
B)anticodon.
C)amino acid.
D)transcript.
E)templatE.

Question 25

The many different functions and behaviors of living organisms are essentially based on the performance of their cells.The cells' performance in turn is dependent upon the

A)production of many varieties of polypeptides and proteins.
B)production of correct membranes.
C)proper conformation for water in the cells.
D)production of steroids and hormones.
E)ability to reproducE.

Question 26

The sites A,P,and E are progressively occupied by amino acids being assembled into a chain in protein synthesis.These sites are part of

A)small ribosomal subunit.
B)large ribosomal subunit.
C)mRNA.
D)tRNA.
E)DNA (the gene itself).

Question 27

How many unique mRNA codons can be constructed from the four different RNA nucleotides?

A)4
B)8
C)16
D)32
E)64

Question 28

Similar to the complementary purine-pyrimidine relationship observed in DNA,which of the following choices pairs with adenine in RNA?

A)thymine
B)cytosine
C)guanine
D)uracil

Question 29

Each amino acid has a specific tRNA molecule that can transport it to the site of protein synthesis.Therefore,in humans the number of different tRNA molecules would be

A)3.
B)20.
C)40.
D)80.
E)thousands.

Question 30

The genetic code operates on all the following principles except

A)all four of the nucleotide bases must be used.
B)each combination of any three nucleotides can act as a codon.
C)the first nucleotide in every codon is always the same.
D)a particular codon always specifies the same amino aciD.

Question 31

In eukaryotic cells,mRNA is made as a copy of the DNA coding information in the

A)cytoplasm.
B)mitochondria.
C)ER.
D)nucleus.
E)plasma membranE.

Question 32

Protein synthesis takes place on

A)the plasma membrane.
B)the nucleus.
C)ribosomes.
D)lysosomes.
E)microbodies.

Question 33

The nucleotide sequence of a mRNA codon is composed of how many bases?

A)1
B)2
C)3
D)16
E)64

Question 34

Besides the triplet nature of the genetic code,the other major piece of information that was provided by Crick and his coworkers is that

A)each codon specified a different amino acid.
B)the code of all DNA molecules is the same.
C)the proteins made from the coded information are always the same.
D)the reading of the code occurs without any punctuation.
E)the genetic code is the same in all organisms with no exceptions.

Question 35

The number of nucleotides required to specify an amino acid is

A)1.
B)2.
C)3.
D)4.
E)a variable number.

Question 36

Because nucleic acid sequence information is changed into amino acid sequence information,polypeptide synthesis is known as

A)breaking the code.
B)decoding.
C)transcription.
D)translocation.
E)translation.

Question 37

Gene expression includes which two of the following processes?

A)transcription and replication
B)replication and repression
C)protein synthesis and replication
D)mutation and cell division
E)transcription and translation

Question 38

The hereditary information in DNA is conveyed through the

A)production of all three kinds of RNA molecules.
B)production of a lipid bilayer.
C)production of DNA copies.
D)production of many proteins and polypeptides.
E)production of all of the codons.

Question 39

The tRNA nucleotide sequence that lines up on the mRNA is

A)an intron.
B)an exon.
C)a release factor.
D)an initiation factor.
E)an anticodon.

Question 40

The enzyme that initiates transcription is

A)RNA polymerase.
B)DNA polymerase.
C)carbonic anhydrase.
D)ATP synthetase.
E)transformation principlE.

Question 41

Humans and a bacterium make human insulin.How is this possible?

A)The human insulin gene appears naturally in the bacteriA.
B)The human insulin gene is a mutated form of a bacterial gene for bacterial insulin.
C)The human insulin gene was inserted into a bacterium's genome,and since the genetic code is nearly universal,the bacterium is able to produce human insulin.
D)The human insulin gene appears in bacteria that have been exposed to radiation treatments for diabetes.
E)The human insulin gene appears naturally in the bacteria that is an inhabitant of the GI tract of diabetic patients.

Question 42

Specific amino acids are attached to tRNA molecules by

A)activating enzymes.
B)codons.
C)anticodons.
D)ribosomes.
E)initiation factors.

Question 43

Eukaryotic mRNA molecules are occasionally interspersed with non-coding sequences that must be removed before protein synthesis.These are called

A)anticodons.
B)introns.
C)exons.
D)nucleosomes.
E)chromomeres.

Question 44

The Central Dogma of biology is stated as

A)proteins $\rarr$ RNA $\rarr$ DNA.
B)RNA $\rarr$ DNA $\rarr$ proteins.
C)DNA $\rarr$ proteins $\rarr$ RNA.
D)DNA $\rarr$ RNA $\rarr$ proteins.

Question 45

The bond that forms between the newly added amino acid and the previous amino acid on the chain is called a

A)hydrogen bond.
B)hydrophobic bond.
C)hydrophilic bond.
D)phosphodiester bonD.
E)peptide bond.

Question 46

The different components of the protein synthesizing machinery include all of the following except

A)mRNA.
B)tRNA.
C)ribosomes.
D)amino acids.
E)RNA polymerasE.

Question 47

Eukaryotic organisms and prokaryotic organisms differ in how gene information is processed.Select the statement that best explains this difference.

A)Prokaryote genes are transcribed into mRNA,which is translated immediately.Eukaryote genes contain long sequences of nucleotides that do not code for amino acids and have to be removed from the primary transcript.
B)Prokaryote genes are transcribed directly into a polypeptide,while eukaryote genes have mRNA and tRNA involved in polypeptide assembly.
C)Prokaryote genes are translated before being transcribed into mRNA.Eukaryotic genes are transcribed into mRNA and then translated.
D)Prokaryote genes are edited of all introns before being transcribed into mRNA,while eukaryotic genes are edited after mRNA formation.

Question 48

Initiation of transcription differs from initiation of DNA replication in several ways.One such difference is that transcription does not require

A)GTP or ATP.
B)any enzymes.
C)a primer.
D)a DNA template stranD.

Question 49

In eukaryotes,mRNA processing involves all of the following events except

A)elongation of the transcript.
B)addition of a 5' cap.
C)addition of a poly A to the 3' end.
D)pre-mRNA splicing.
E)association with the spliceosomE.

Question 50

There are 45 different kinds tRNA (anticodons)available to serve as amino acid carriers,but there are 64 mRNA codons.Why aren't the tRNA anticodons and mRNA codons equal in number?

A)The reason is that the third base pair on the tRNA allows some flexibility (wobble);thus,some tRNA anticodons can recognize more than one mRNA codon.
B)The reason is that some tRNA anticodons can misread some of the mRNA codons,which creates a "wobble" in the tRNA anticodons that can be repaired by RNA repair enzymes.
C)The reason is that the third base pair on the mRNA codon allows some flexibility (wobble);thus,some tRNA anticodons can recognize more than one mRNA codon.
D)The reason is that the tRNA has the flexibility to choose which mRNA codons are necessary for building the polypeptide chain.

Question 51

The codons that serve as "stop" signals for the protein synthesis are called

A)anticodons.
B)release codons.
C)nonsense codons.
D)amino acid codons.
E)tRNA codons.

Question 52

The transfer of information from DNA to mRNA is referred to as

A)transcription.
B)translation.
C)transformation.
D)transference.
E)translocation.

Question 53

The process that occurs when a ribosome moves three more nucleotides along the mRNA molecule in the 5' to 3' direction is referred to as

A)transduction.
B)translation.
C)translocation.
D)transposon.

Question 54

Transcription is the first stage in the Central Dogma.Transcription is initiated by

A)DNA polymerase binding to the promoter.
B)RNA polymerase binding to the promoter.
C)mRNA polymerase binding to the promoter.
D)tRNA polymerase binding to the promoter.

Question 55

Which of the following best identifies the various types of RNA that play a role in protein synthesis in eukaryotes?

A)mRNA,rRNA,tRNA,snRNA,SRP RNA,and miRNA
B)mRNA,rRNA,tRNA,SRP RNA,and miRNA
C)mRNA,rRNA,tRNA,and snRNA
D)mRNA,rRNA,tRNA,snRNA,and SRP RNA
E)mRNA,rRNA,and tRNA

Question 56

The location of protein synthesis in eukaryotic cells is the

A)nucleus.
B)cytoplasm.
C)plasma membrane.
D)Golgi apparatus.
E)vacuolE.

Question 57

If the DNA triplet code were ATG CGT,the tRNA anticodons would be

A)AUG CGU.
B)ATG CGT.
C)UAC GCA.
D)UAG CGU.

Question 58

If the sequence of bases in a section of DNA is ATCGCTCC,what is the corresponding sequence of bases in mRNA?

A)ATCCGATT
B)TAGGCUGG
C)UAGCGAGG
D)TATCGGCC
E)AUCCGAUU

Question 59

The initiation complex for protein synthesis contains all of the following except

A)a small ribosomal subunit.
B)mRNA.
C)tRNA with methionine.
D)a release factor.
E)an initiation factor.

Question 60

In eukaryotes,the empty RNA molecules exit the ribosome from the

A)E site.
B)P site.
C)A site.
D)active site.
E)allosteric sitE.

Question 61

The given sequence

A)is from a prokaryote.
B)is from a eukaryote.
C)can be from either a prokaryote or a eukaryote.
D)is from neither a prokaryote nor a eukaryote.

Question 62

Translated,the corresponding protein contains how many amino acids?

A)6
B)7
C)8
D)13

Question 63

RNA splicing in eukaryotic cell protein synthesis means

A)that the product of translation,called the primary transcript is cut and put back together to produce the mature mRNA transcript.
B)that the product of transcription,called the secondary transcript is cut and put back together to produce the mature tRNA transcript.
C)that the product of translation,called the primary transcript is cut and put back together to produce the mature tRNA transcript.
D)that the product of transcription,called the primary transcript is cut and put back together to produce the mature mRNA transcript.

Question 64

Of the types of RNA polymerase that are known,which one is the most complex?

A)I
B)II
C)III
D)IV

Question 65

The basic genetic information of the cell;contained in chromosomes.

A)DNA
B)RNA polymerase
C)mRNA
D)rRNA

Question 66

Why are there only 45 different tRNA anticodons rather than 64 to match each of the mRNA codons?

A)The first nucleotide of a tRNA anticodon allows some flexibility or "wobble."
B)The second nucleotide of a tRNA anticodon allows some flexibility or "wobble."
C)The third nucleotide of a tRNA anticodon allows some flexibility or "wobble."
D)The remaining 19 tRNA anticodons are used for initiation and termination of protein synthesis.

Question 67

Noncoding DNA that interrupt the nucleotide sequence of a gene are called

A)exons.
B)introns.
C)axons.
D)anRNPs (snurps).
E)spliceosomE.

Question 68

Given the sentence "THE FAT CAT ATE THE RED RAT," which of the following would represent a frameshift mutation?

A)THE FAT CAT ATE THE RED RAT
B)THE CAT ATE THE RED RAT
C)THE FAC ATA TET HER EDR AT
D)THE FAT RAT ATE THE RED RAT

Question 69

Exists as a complex with many large proteins in ribosomes;many different kinds of molecules.

A)DNA
B)RNA polymerase
C)mRNA
D)rRNA

Question 70

What is the anticodon for the fourth codon?

A)AGC
B)UCG
C)GAU
D)CUA

Question 71

Prokaryotes have one type of RNA polymerase.Eukaryotes have ____ types of RNA polymerase.

A)2
B)3
C)4
D)16
E)64

Question 72

Eukaryotic mRNA molecules are modified

A)in the cytoplasm.
B)at the ribosome.
C)in the nucleus.
D)at the Golgi complex.
E)at the initiation of transcription.

Question 73

An enzyme that synthesizes all three forms of RNA;present in the nucleus of eukaryotes.

A)DNA
B)RNA polymerase
C)mRNA
D)rRNA

Question 74

What would happen if snRNAs could not recognize the branch point?

A)A lariat structure could not form.
B)snRNAs could not base-pair with the 5' end of the intron.
C)The 3' poly A tail could not be added to the transcript.
D)The 5' cap could not be added to the transcript.

Question 75

The 3' Poly-A tail is attached to

A)the Poly-A polymerase enzyme.
B)the mRNA.
C)the tRNA.
D)the coding strand of the DNA molecule.
E)the template strand of the DNA moleculE.

Question 76

You are conducting a genetic screen to isolate nutritional mutants in yeast.Specifically,you want to isolate a histidine leucine double mutant.You start with a wild type yeast strain and mutagenize it with a UV light.Which of the following outlines the remaining steps for isolating such a mutant?

A)Grow mutagenized yeast on rich mediA.Grow yeast on minimal media,as well as on minimal media containing histidine,minimal media containing leucine,and minimal media containing both histidine and leucine.Select for yeast that do not grow on minimal media,do not grow on media supplemented with only histidine or leucine,but do grow on minimal media supplemented with both histidine and leucine.
B)Grow mutagenized yeast on minimal media.Grow yeast on rich media,as well as on minimal media containing histidine,minimal media containing leucine,and minimal media containing both histidine and leucine.Select for yeast that do not grow on rich media,do not grow on media supplemented with only histidine or leucine,but do grow on minimal media supplemented with both histidine and leucine.
C)Grow mutagenized yeast on rich media.Grow yeast on minimal media,as well as on minimal media containing histidine,minimal media containing leucine,and minimal media containing both histidine and leucine.Select for yeast that grow on minimal media,grow on media supplemented with only histidine or leucine,but do not grow on minimal media supplemented with both histidine and leucine.
D)Grow mutagenized yeast on minimal media.Grow yeast on rich media,as well as on minimal media containing histidine,minimal media containing leucine,and minimal media containing both histidine and leucine.Select for yeast that grow on rich media,grow on media supplemented with only histidine or leucine,but do not grow on minimal media supplemented with both histidine and leucine.

Question 77

Which type of RNA is thought to help protect cells from viral attack?

A)sn RNA
B)siRNA
C)SRP RNA
D)mRNA

Question 78

Translocation is a process that involves

A)moving of mRNA molecules.
B)moving of the aminoacyl-tRNA synthetases.
C)the actual moving of the amino acids to the ribosomes by the tRNA molecules.
D)the ribosome moving one more nucleotide along the mRNA molecule.
E)the ribosome moving three more nucleotides along the mRNA moleculE.

Question 79

Transcription in prokaryotes is carried out by the enzyme _______,which unwinds and transcribes the gene.

A)DNA polymerase
B)DNA helicase
C)DNA gyrase
D)RNA ligase
E)RNA polymerase

Question 80

Single long strand that passes from the nucleus to the cytoplasm in eukaryotes;contains information for polypeptide assembly.

A)DNA
B)RNA polymerase
C)mRNA
D)rRNA