Chapter 17 Vocabulary

Question 1

A modified form of guanine nucleotide added onto the nucleotide at the 5’ end of a pre-mRNA molecule

Answer 1

5’ cap

Question 2

A type of eukaryotic gene regulation at the RNA-processing level in which different mRNA molecules are produced from the primary transcript, depending on which RNA segments are treated as exons and which as introns.

Answer 2

Alternative RNA splicing

Question 3

An organic molecule possessing both carboxyl and amino groups. These serve as the monomers of polypeptides.

Answer 3

Amino acid

Question 4

An enzyme that joins each amino acid to the appropriate tRNA.

Answer 4

aminoacyl-tRNA synthetase

Question 5

A nucleotide triplet at one end of a tRNA molecule that recognizes a particular complementary codon on an mRNA molecule.

Answer 5

Anticodon

Question 6

A type of point mutation; the replacement of one nucleotide and its partner in the complementary DNA strand by another pair of nucleotides.

Answer 6

Base-pair substitution

Question 7

A protein molecule that assists in the proper folding of other proteins.

Answer 7

Chaperonin

Question 8

A three-nucleotide sequence of DNA or mRNA that specifies a particular amino acid or termination signal; the basic unit of the genetic code.

Answer 8

Codon

Question 9

An independently folding part of a protein.

Answer 9

Domain

Question 10

Collection of membranes inside and around a eukaryotic cell, related either through direct physical contact or by the transfer of membranous vesicles; includes the smooth and rough ER, Golgi apparatus, lysosomes, and vacuoles

Answer 10

Endomembrane system

Question 11

A sequence within a primary transcript that remains in the RNA after RNA processing; also refers to the region of DNA from which this sequence was transcribed.

Answer 11

Exon

Question 12

A mutation occurring when the number of nucleotides inserted or deleted is not a multiple of three, resulting in the improper grouping of subsequent nucleotides into codons.

Answer 12

Frame-shift mutation

Question 13

The process by which DNA directs the synthesis of proteins or, sometimes, just RNAs

Answer 13

Gene expression

Question 14

Mutation that involves the addition of one or more nucleotide pairs to a gene.

Answer 14

Insertion

Question 15

A noncoding, intervening sequence within a primary transcript that is removed from it during RNA processing; also refers to the region of DNA from which this sequence was transcribed.

Answer 15

Intron

Question 16

Type of RNA, synthesized using a DNA template, that attaches to ribosomes in the cytoplasm and specifies the primary structure of a protein.

Answer 16

Messenger RNA (mRNA)

Question 17

Base-pair mutation that results in a codon that codes for a different amino acid.

Answer 17

Missense mutation

Question 18

Chemical or physical agent that interacts with DNA and causes a mutation.

Answer 18

Mutagen

Question 19

Mutation that changes an amino acid codon to one of the three stop codons, resulting in a shorter and usually nonfunctional protein.

Answer 19

Nonsense mutation

Question 20

A change in a gene at a single nucleotide pair.

Answer 20

Point mutation

Question 21

A sequence of 50 to 250 adenine nucleotides added onto the 3’ end of a pre-mRNA molecule.

Answer 21

Poly-A tail

Question 22

A group of several ribosomes attached to, and translating, the same messenger RNA molecule.

Answer 22

Polyribosome (polysome)

Question 23

An initial RNA transcript; also called pre-mRNA when transcribed from a protein-coding gene.

Answer 23

Primary transcript

Question 24

Specific nucleotide sequence in DNA that binds RNA polymerase, positioning it to start transcribing RNA at the appropriate place.

Answer 24

Promoter

Question 25

Most abundant type or RNA, which together with proteins makes up ribosomes.

Answer 25

Ribosomal RNA (rRNA)

Question 26

Complex of rRNA and protein molecules that functions as a site of protein synthesis in the cytoplasm; consists of a large and a small subunit. In eukaryotic cells, each subunit is assembled in the nucleolus.

Answer 26

Ribosome

Question 27

AN RNA molecule that functions as an enzyme, catalyzing reactions during RNA splicing.

Answer 27

Ribozyme

Question 28

An enzyme that links ribonucleotides into a growing RNA chain during transcription.

Answer 28

RNA polymerase

Question 29

Modification of RNA transcripts, including splicing out of introns, joining together of exons, and alteration of the 5' and 3' ends.

Answer 29

RNA processing

Question 30

After synthesis of a eukaryotic primary RNA transcripts, the removal of proteins (introns) of the transcript that will not be included in the mRNA.

Answer 30

RNA splicing

Question 31

Sequence of about 20 amino acids at or near the leading (amino) end of a polypeptide that targets it to the endoplasmic reticulum or other organelles in a eukaryotic cell.

Answer 31

Signal peptide

Question 32

Protein-RNA complex that recognizes a signal peptide as it emerges from a ribosome and helps direct the ribosome to the endoplasmic reticulum (ER) by binding to a receptor protein on the ER.

Answer 32

Signal-recognition particle (SRP)

Question 33

Large complex made up of proteins and RNA molecules that splices RNA by interacting with the ends of an RNA intron, releasing the intron and joining two adjacent exons.

Answer 33

Spliceosome

Question 34

DNA sequence in eukaryotic promoters crucial in forming the transcription initiation complex.

Answer 34

TATA box

Question 35

DNA strand that provides the pattern, or template, for ordering the sequence of nucleotides in an RNA transcripts.

Answer 35

Template strand

Question 36

In bacteria, a sequence of nucleotides in DNA that marks the end of a gene and signals RNA polymerase to release the newly made RNA molecule and detach from the DNA.

Answer 36

Terminator

Question 37

Synthesis of RNA using a DNA template.

Answer 37

Transcription

Question 38

A regulatory protein that binds to DNA and affects transcription of specific genes.

Answer 38

Transcription factor

Question 39

Completed assembly of transcription factors and RNA polymerase bound to a promoter.

Answer 39

Transcription initiation complex

Question 40

RNA molecule that functions as an interpreter between nucleic acid and protein language by picking up specific amino acids and recognizing the appropriate codons in the mRNA.

Answer 40

Transfer RNA (tRNA)

Question 41

Synthesis of a polypeptide using the genetic information encoded in an mRNA molecule. There is a change of "language" from nucleotides to amino acids.

Answer 41

Translation

Question 42

Flexibility in the base-pairing rules in which nucleotide at the 5' end of a tRNA anticodon can form hydrogen bonds with more than one kind of base in the third position (3' end) of a codon.

Answer 42

Wobble