Chapter 21 Pt. 2

Question 1

What are the three types of RNA produced in cells?

Answer 1

(1) Messenger RNA (mRNA)
(2) Transfer RNA (tRNA)
(3) Ribosomal RNA (rRNA)

Question 2

Which type of RNA is this:

carries DNA’s information in the sequence of its bases (condons) from the nucleus to the cytoplasm

Answer 2

Messenger RNA (mRNA)

Question 3

Which type of RNA is this:

binds to a specific amino acid and transports it to be added, as appropriate, to a growing polypeptide chain

Answer 3

Transfer RNA (tRNA)

Question 4

Which type of RNA is this:

combines with protein to form ribosomes (structures on which polypeptides are synthesized)

Answer 4

Ribosomal RNA (rRNA)

Question 5

The process of transcription:

(1)
(2) RNA nucleotides pair with the complementary DNA bases and are linked together to form an RNA transcript

(3) The RNA transcript is released from the DNA

Answer 5

(1) the segment of DNA to be transcribe unwinds

Question 6

The process of transcription:

1) the segment of DNA to be transcribe unwinds
(2
(3) The RNA transcript is released from the DNA

Answer 6

(2) RNA nucleotides pair with the complementary DNA bases and are linked together to form an RNA transcript

Question 7

The process of transcription:
(1) the segment of DNA to be transcribe unwinds
(2) RNA nucleotides pair with the complementary DNA bases and are linked together to form an RNA transcript
(3)

Answer 7

(3) The RNA transcript is released from the DNA

Question 8

________-the signal to start transcription is given by a specific sequence of bases on DNA

Answer 8

promoter

Question 9

What is an RNA polymerase?

Answer 9

enzyme that binds with the promoter on DNA and then moves along the DNA strand

Question 10

These unexpressed regions of DNA are called ______, short for __________ ___________

Answer 10

introns

intervening sequences

Question 11

The remaining segments of DNA or mRNA, called ______ for _________ ___________, splice together to form the sequence that directs the synthesis of a protein

Answer 11

exons

expressed sequences

Question 12

What is translation?

Answer 12

converts the nucleotide language of mRNA into the amino acid language of a protein

Question 13

Translation:

____->_______

Answer 13

RNA

Protein

Question 14

_______ _____-the “language” of genes that translates the sequences of bases in DNA into the specific sequences of amino acids in a protein

Answer 14

genetic code

Question 15

What are codons?

Answer 15

sequences of three bases on mRNA that specify 1 of the 20 amino acids or the begging or end of the protein chain

Question 16

The four bases in RNA (A,U,G,C) could form ___ combos of 3-base sequences

Answer 16

64

Question 17

True or False: the number of possible amino acids, in RNA, exceeds the number of codons

Answer 17

False; the number of possible codons, in RNA , exceeds the number of amino acids

Question 18

What are the stop codons?

Answer 18

UAA
UAG
UGA

Question 19

A tRNA molecule must be able to recognize both the ______ on ______ and the ______ _____ that the codon specifies

Answer 19

codon
mRNA
amino acid

Question 20

How does the tRNA know the correct location along mRNA?

Answer 20

its determined by the anticodon, a sequence of three nucleotides on the tRNA

Question 21

What is the role of the anticodon?

Answer 21

it “reads” the language of mRNA by binding to a codon on the mRNA molecule according to the complementary base-pairing rules

Question 22

A ________ consists of 2 subunits (small and large), each composed of ribosomal RNA (rRNA) and protein

Answer 22

ribosome

Question 23

A ribosome consists of 2 subunits (small and large), each composed of _________ ___ (_____) and ______

Answer 23

ribosomal RNA (rRNA)
protein

Question 24

The subunits, of ribosomes, form in the ________ and are shipped to the _________

Answer 24

nucleus

cytoplasm

Question 25

What is the role of the ribosome in protein synthesis?

Answer 25

to bring the tRNA bearing an amino acid close enough to the mRNA to interact

Question 26

What are the three stages of translation?

Answer 26

(1) Initiation
(2) Elongation
(3) Termination

Question 27

Which stage of translation is this:

the major players in protein synthesis (mRNA, tRNA, and ribosomes) come together

Answer 27

Initiation

Question 28

Which stage of translation is this:

of the protein occurs a additional amino acids are added to the chain

Answer 28

Elongation

Question 29

Which stage of translation is this:

occurs when a stop codon moves into the ribosome

Answer 29

Termination

Question 30

The steps of initiation:
1.

2. A tRNA with complementary anticodon pairs with the start codon. Ribosomal subunits join to form a functional ribosome

Answer 30

1. the small ribosomal subunit joins to mRNA at the start codon, AUG

Question 31

The steps of initiation:
1. the small ribosomal subunit joins to mRNA at the start codon, AUG

2.

Answer 31

2. A tRNA with complementary anticodon pairs with the start codon. Ribosomal subunits join to form a functional ribosome

Question 32

The steps of elongation:

2. peptide bond formation
3. ribosome movement

Answer 32

1. codon recognition

Question 33

The steps of elongation:

1. codon recognition
3. ribosome movement

Answer 33

2. peptide bond formation

Question 34

The steps of elongation:
1. codon recognition
2. peptide bond formation
3.

Answer 34

3. ribosome movement

Question 35

The steps of termination:

2. parts disassemble

Answer 35

1. stop codon moves into ribosome

Question 36

The steps of termination:
1. stop codon moves into ribosome
2.

Answer 36

2. parts disassemble

Question 37

What is a polysome?

Answer 37

a group of ribosomes reading the same mRNA molecule