Chapter 14 Vocab

Question 1

the process by which DNA directs the synthesis of proteins or, in some cases, just RNAs

Answer 1

gene expression

Question 2

the synthesis of RNA using a DNA template

Answer 2

transcription

Question 3

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

Answer 3

messenger RNA

Question 4

the synthesis of a polypeptide using the genetic information encoded in an mRNA molecule

Answer 4

translation

Question 5

a complex of rRNA and protein molecules that functions as a site of protein synthesis in the cytoplasm

Answer 5

ribosome

Question 6

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

Answer 6

primary transcript

Question 7

a set of three-nucleotide-long words that specify the amino acids for polypeptide chains

Answer 7

triplet code

Question 8

the DNA strand that provides the pattern for ordering the sequence of nucleotides in an RNA transcript

Answer 8

template strand

Question 9

a three nucleotide sequence of mRNA that specifies a particular amino acid or termination signal

Answer 9

codon

Question 10

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

Answer 10

reading frame

Question 11

an enzyme that links ribonucleotides into a growing RNA chain during transcription

Answer 11

RNA polymerase

Question 12

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

Answer 12

<promoter

Question 13

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 13

terminator

Question 14

a region of DNA that is transcribed into an RNA molecule

Answer 14

transcription unit

Question 15

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

Answer 15

transcription factor

Question 16

the completed assembly of transcription factors and RNA polymerase bound to the promoter

Answer 16

transcription initiation complex

Question 17

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

Answer 17

TATA box

Question 18

modification of RNA transcripts, including splicing out of introns, joining together of exons, and alteration of the 5’ and 3’ ends

Answer 18

RNA processing

Question 19

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

Answer 19

5’ cap

Question 20

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

Answer 20

poly A tail

Question 21

after synthesis of a eukaryotic primary RNA transcript, the removal of portions (introns) of the transcript that will not be included in the mRNA

Answer 21

RNA splicing

Question 22

a noncoding, intervening sequence within a primary transcript that is removed from the transcript during RNA processing

Answer 22

intron

Question 23

a sequence within a primary transcript that remains in the RNA after RNA processing

Answer 23

exon

Question 24

a 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 the two adjacent exons

Answer 24

spliceosome

Question 25

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

Answer 25

ribozyme

Question 26

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

Answer 26

alternative RNA splicing

Question 27

an independently folding part of a protein

Answer 27

domain

Question 28

an 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 28

transfer RNA

Question 29

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

Answer 29

anticodon

Question 30

flexibility in the base-pairing rules in which the 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 30

wobble

Question 31

the most abundant type of RNA, which together with proteins makes up ribosomes

Answer 31

ribosomal RNA

Question 32

the place on a ribosome that holds the tRNA carrying the next amino acid to be added to the polypeptide chain

Answer 32

A site

Question 33

the place on a ribosome that holds the tRNA carrying the growing polypeptide chain

Answer 33

P site

Question 34

the place on a ribosome where discharged tRNAs leave the ribosome

Answer 34

E site

Question 35

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

Answer 35

polyribosome

Question 36

a 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 eukarytoic cell

Answer 36

signal peptide

Question 37

a 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 37

signal recognition particle

Question 38

a change in the nucleotide sequence of an organism's DNA, ultimately creating genetic diversity

Answer 38

mutation

Question 39

a change in a gene at a single nucleotide pair

Answer 39

point mutation

Question 40

a type of point mutation where one nucleotide and its partner in the complementary DNA strand are replaced by another pair of nucleotides

Answer 40

base pair substitution

Question 41

a base-pair substitution that results in a codon that codes for a different amino acid

Answer 41

missense mutation

Question 42

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

Answer 42

nonsense mutation

Question 43

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

Answer 43

insertion

Question 44

a mutational loss of one or more nucleotide pairs from a gene

Answer 44

deletion

Question 45

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

Answer 45

frameshift mutation

Question 46

a chemical or physical agent that interacts with DNA and causes a mutation

Answer 46

mutagen

Question 47

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

Answer 47

aminoacyl-tRNA synthetase