Chapter 9

Question 1

what is the site of protein synthesis in the cell?

Answer 1

ribosomes

Question 2

proteins are long chains of ____

Answer 2

amino acids

Question 3

instructions for proteins are on ____

Answer 3

DNA

Question 4

____ is the messenger that transports information from the DNA to the ribosomes

Answer 4

mRNA

Question 5

describe the process

Answer 5

DNA to RNA to ribosomes to proteins

Question 6

DNA is first transcribed to form ____, then RNA is translated to form ____

Answer 6

messenger RNA, polypeptide chains (proteins)

Question 7

characteristics of RNA

a. ) ____ stranded
b. ) contains ____ instead of thymine
c. ) the five-carbon sugar is called…

Answer 7

single, uracil, ribose

Question 8

what are the three types of RNA?

Answer 8

messenger RNA, transfer RNA, ribosomal RNA

Question 9

RNA nucleitides are added in the ____ to ____ direction

Answer 9

5, 3

Question 10

____ catalyzes the addition of nucleotides on the RNA strand

Answer 10

RNA polymerase

Question 11

a ____ is a base sequence of DNA that signals the start of the gene

Answer 11

promoter

Question 12

what binds to the promoter before transcription can begin?

Answer 12

RNA polymerase

Question 13

eukaryotic DNA has exons and introns. which are the part of the DNA that is expressed as genes? what are the segments between the exons that are not expressed?

Answer 13

exons, introns

Question 14

mRNA is only assembled from ____, and ____ are snipped out during transcription

Answer 14

exons, introns

Question 15

the RNA segment is transcribed in…

Answer 15

codons

Question 16

a codon is how many base pairs long?

Answer 16

3

Question 17

how many different codons are there?

Answer 17

64. sixty-one specify an amino acid, and three are stop codons.

Question 18

how many amino acids are there?

Answer 18

20

Question 19

how many codons code for an amino acid?

Answer 19

more than one

Question 20

tRNA transcribes codons from mRNA by the ____ on the tRNA

Answer 20

anticodons

Question 21

tRNA brings the specified amino acid to the attachment site of the ribosome for ____

Answer 21

elongation

Question 22

stages of RNA

1. ) ____ - tRNA binds to small subunit RNA
2. ) ____ - tRNA then brings correct order of amino acids for assembly
3. ) ____ - at a stop codon, tRNA has no anticodon for stop codon; protein is complete

Answer 22

initiation, elongation, termination

Question 23

mutations

a. ) ____ - a base pair is substituted
b. ) ____ - extra base added
c. ) ____ - base removed

Answer 23

base pair substitution, insertion, deletion

Question 24

gene segments that move spontaneously about the genome are called…

Answer 24

spontaneous mutations

Question 25

only gene mutations that arise in ____ can pass on to the next generation

Answer 25

gametes (eggs/sperm)