Chapter 17

Question 1

Transcription

Answer 1

The synthesis of RNA using template DNA

Question 2

Translation

Answer 2

Synthesis of polypeptide using the information in the mRNA.

Question 3

Primary transcript

Answer 3

An initial RNA transcript from any gene

Question 4

Triplet code

Answer 4

information system that uses a series of 3 nucleotides to specify a sequence of amino acids for a polypeptide

Question 5

Template strand

Answer 5

The DNA strand that provides the template for the order of polypeptides

Question 6

Codons

Answer 6

3 nucleotide sequence of polynucleotide that specifies an amino acid or termination signal

Question 7

Coding strand

Answer 7

Non-template DNA strand that the same sequence as mRNA

Question 8

Reading frame

Answer 8

On mRNA, the triplet grouping of ribonucleotides used by the translation machinery during polypeptide synthesis

Question 9

RNA polymerase

Answer 9

An enzyme that links ribonucleotides into growing RNA chain during transcription

Question 10

Promotor

Answer 10

Specific nucleotide sequence in DNA of a gene that binds RNA polymerase, so it can transcribe in the right place

Question 11

Terminator

Answer 11

Sequence of DNA that marks the end of a gene and signals RNA polymerase to release it

Question 12

Transcription unit

Answer 12

Region of DNA that is transcribed into an RNA molecule

Question 13

Startpoint

Answer 13

The nucleotide position on the promotor where RNA polymerase begins synthesis of RNA

Question 14

Transcription factors

Answer 14

protein that binds to DNA & affect transcription of genes

Question 15

Transcription initiation complex

Answer 15

The completed assembly of transcription factors and RNA polymerase on promoter

Question 16

TATA Box

Answer 16

Dna sequence in eukaryotic promoters crucial in forming the transcription complex

Question 17

RNA processing

Answer 17

Modification of pre-mRNA, by removing introns, joining exons, & alteration of 5’ & 3’ ends

Question 18

5’ cap

Answer 18

Modified form of guanine nucleotide added to 5’ end of pre-mRNA (GTP)

Question 19

Poly-A tail

Answer 19

Sequence of adenine nucleotides added onto the 3’ end of a pre mRNA

Question 20

RNA splicing

Answer 20

Removal of introns in the mRNA and joining exons

Question 21

Introns

Answer 21

Noncoding intervening sequence within a pre-mRNA that’s removed from transcript

Question 22

Exons

Answer 22

Sequence within primary mRNA that remains after processing

Question 23

Spliceosome

Answer 23

Large complex made up of proteins and RNA that splices that splices RNA

Question 24

Ribozymes

Answer 24

Rna molecule that acts as an enzyme

Question 25

Transfer RNA

Answer 25

RNA molecule that functions in translation by applying specific amino acid to polypeptide chain in ribosome

Question 26

Anticodon

Answer 26

A nucleotide triplet at an end of tRNA that base pairs with a codon on mRNA

Question 27

Aminoacyl-tRNA synthase

Answer 27

An enzyme that joins each amino acid to appropriate tRNA

Question 28

Charged tRNA

Answer 28

tRNA covalently bonded to an amino acid

Question 29

Wobble

Answer 29

Flexibility in base-pairing where the nucleotide at the 5’ end of a tRNA anticodon can hydrogen bond with more than one kind of base in third position (3’ end) of codon

Question 30

Ribosomal RNA

Answer 30

RNA molecule combined with proteins, to make ribosomes

Question 31

Translation initiation complex

Answer 31

Union of mRNA, initiator tRNA, and ribosomal subunit followed by attachment of a large ribosomal subunit

Question 32

N-terminus

Answer 32

Methionine

Question 33

C-terminus

Answer 33

Carboxyl end

Question 34

Codon recognition

Answer 34

Anticodon of incoming charged tRNA base pairs with complementary codon

Question 35

Peptide bond formation

Answer 35

An rRNA molecule of large subunit forms peptide bond between carboxyl end of polypeptide and new amino acid in A site

Question 36

Translocation

Answer 36

The ribosome translocated tRNA in A site to P site. tRNA in P site moves to E site where it’s released from ribosome

Question 37

Release factor

Answer 37

Proteins shaped like charged tRNA

Question 38

Signal peptide

Answer 38

Sequence of 20 amino acids at or near N-terminus that targets ribosome to ER

Question 39

Signal recognition particle

Answer 39

Protein RNA complex that recognize a signal peptide as it emerges from a ribosome, and it helps direct the ribosome to ER by binding to receptor protein on ER

Question 40

Polyribosome

Answer 40

Group of several ribosomes attaches to, and translating, the same mRNA

Question 41

Point mutation

Answer 41

Change in single nucleotide pair of gene

Question 42

Nucleotide pair substitution

Answer 42

Type of point mutation in which one nucleotide in a DNA strand and its partner in the complementary strand are replaced

Question 43

Silent mutation

Answer 43

A new nucleotide pair substitution that has no observable effects on phenotype

Question 44

Missense production

Answer 44

A nucleotide pair substitution that results in a codon that codes for different amino acid

Question 45

Nonsense mutation

Answer 45

A mutation that changes an amino acid codon to one of the 3 stop codons

Question 46

Insertions

Answer 46

A mutation involving the addition of one or more nucleotide pairs to a gene

Question 47

Deletion

Answer 47

A subtraction of one or more nucleotide pairs to a gene

Question 48

Frameshift mutation

Answer 48

Occurring when nucleotides are inserted or deleted from a gene in non multiples of 3

Question 49

Mutagens

Answer 49

Chemical or physical agent that interacts with DNA and can cause a mutation