Chapter 17

Question 1

Gene Expression

Answer 1

The process by which DNA directs protein synthesis

Question 2

Two stages of Gene expression

Answer 2

transcription and translation

Question 3

Transcription

Answer 3

The synthesis of RNA using information in DNA

Question 4

messenger RNA (mRNA)

Answer 4

What is produced in transcription. Will be used in translation to help create proteins

Question 5

Translation

Answer 5

the synthesis of a polypeptide, using information in the mRNA

Question 6

Ribosomes

Answer 6

the sites of translation

Question 7

In prokaryotes, translation of mRNA can begin…

Answer 7

before transcription has finished

Question 8

In eukaryotic cells, the nuclear envelope…

Answer 8

separates transcription from translation

Question 9

Primary transcript

Answer 9

the initial RNA transcript from any gene prior too processing

Question 10

What is the central dogma of gene expression

Answer 10

DNA -> RNA -> Protein

Question 11

triplet code

Answer 11

a series of non overlapping, three-nucleotide words

Question 12

template strand

Answer 12

One of the two DNA strands that provides a template for ordering the sequence of complementary nucleotides in an RNA transcript

Question 13

Codons

Answer 13

The mRNA base triplets that code for specific amino acids. Read in the 5’ -> 3’ direction

Question 14

Codons must be read in the correct __________ in oder for the specified polypeptide to be produced

Answer 14

reading frame

Question 15

RNA polymerase

Answer 15

What catalyzes RNA synthesis. Pries the DNA strands apart and joins together the RNA nucleotides

Question 16

Promoter

Answer 16

The DNA sequence where RNA polymerase attaches

Question 17

Terminator

Answer 17

the sequence signaling the end of transcription

Question 18

transcription unit

Answer 18

The stretch of DNA that is transcribed

Question 19

Three stages of transcription

Answer 19

1) Initiation
2) Elongation
3) Termination

Question 20

Transcription factors

Answer 20

mediate the binding of RNA polymerase and the initiation of transcription

Question 21

Transcription initiation complex

Answer 21

The completed assembly of transcription factors and RNA polymerase II bound to a promoter

Question 22

TATA box

Answer 22

A promoter that is crucial in forming the initiation complex in eukaryotes

Question 23

Activators

Answer 23

boost a gene’s transcription

Question 24

repressors

Answer 24

decrease a gene’s transcription

Question 25

5’ cap

Answer 25

on the 5’ end that is a modified guanine and protects the transcript from being broken down

Question 26

ploy-A tail

Answer 26

on the 3’ end and ends the transcript

Question 27

introns

Answer 27

noncoding regions in RNA

Question 28

exons

Answer 28

part of the RNA that is eventually expressed, usually translated into amino acid sequences

Question 29

RNA splicing

Answer 29

removing introns and joins exons, creating an mRNA molecule with a continuous coding sequence

Question 30

transfer RNA (tRNA)

Answer 30

transfers amino acids to the growing polypeptide in a ribosome

Question 31

anticodon

Answer 31

Contained in the tRNA and has base-pairs that are complementary to the mRNA

Question 32

aminoacyl-tRNA synthetase

Answer 32

the enzyme that matches the tRNA and an amino acid together in the first step of translation

Question 33

Wobble

Answer 33

Flexible pairing at the third base of a codon. Allows some tRNAs to bind to more than one codon

Question 34

ribosomal RNA (rRNA)

Answer 34

One of the subunits of ribosomes along with proteins

Question 35

P site

Answer 35

the site that holds the tRNA that carries the growing polypeptide chain

Question 36

A site

Answer 36

The site that holds the tRNA that carries the next amino acid to be added to the chain

Question 37

E site

Answer 37

The site that is the exit site, where discharged tRNAs leave the ribosome