Chapter 13
How many nucleotides are needed to specify three amino acids?
9
There are 64 codons and 20 amino acids. Which of the following is true? a) Several different codons can specify the same amino acid b) Each codon specifies a different amino acid c) Some amino acids have no link to a codon d) Each amino acid is specified by only one codon
A
Which of the following is a chromosomal mutation? a) inversion b) insertion c) point mutation d) substitutiom
A
Which of the following is true? a) RNA is usually single-stranded b) DNA is usually single-stranded c) DNA contains uracil d) RNA contains thymine
A
Which of the following terms is LEAST closely related to the others? a) spindle fiber b) tRNA c) polypeptide d) anticodon
A
Which type of RNA brings the information in the genetic code from the nucleus to other parts of the cell?
mRNA
A promoter is a
Binding site for RNA polymerase
Unlike DNA, RNA contains
Uracil
The anti-codon AGA is complementary to the mRNA codon TCT
False, UCU
A deletion mutation is shown in line B of figure 13-5
False, duplication
A codon consists of four nucleotides
False, three
What happens during gene expression?
A cell reads the instructions in DNA and builds a protein based on those instructions
What is the difference between a gene mutation and a chromosomal mutation?
A chromosomal mutation can change the number of chromosomes in a cell
A mutation that involves one or a few nucleotides is called
A point mutation
The order of nitrogenous bases in DNA determines the order of ____________ in proteins.
Amino acids
The tRNA bases called the _________ are complementary to three consecutive nucleotides on an mRNA molecule.
Anticodons
When a chromosome undergoes a deletion mutation, information is a) repeated b) lost c) reversed d) transferred
B
Which of the following is true of eukaryotic DNA? a) a promoter is part of an intron b) an intron is part of a promoter c) introns are sequences of DNA d) exons are edited out of pre-mRNA
C
During translation, the type of amino acid that is added to the growing polypeptide depends on the
Codon on the mRNA and the anticodon on the tRNA
During eukaryotic transcription, an RNA molecule is formed that is
Complementary to part of one strand of DNA
Which of the following is true of transcription? a) in eukaryotes, transcription takes place in the cytoplasm and requires many enzymes b) RNA polymerase recognizes and binds to specific regions of the DNA called introns c) RNA editing removes the exons from pre-mRNA, leaving only the introns in the final molecule d) RNA polymerase can make many molecules of RNA from a single DNA sequence
D
From which molecules are mRNA molecules transcribed?
DNA
What is the sequence of the transfer of information in most organisms?
DNA to RNA to protein
According to the chart and figure 13-3, the codes GGA and GGU both code for Ala
False, Gly
During DNA replication, only one strand of DNA serves as a template
False, RNA transcription
Most mutations
Have no effect on an organism
Mutant one in figure 13-7 is the result of a_____________because part of the chromosome reverses direction
Inversion
Which molecules are involved in protein synthesis?
Messenger RNA, ribosomal RNA, and transfer RNA
What is found in both DNA and RNA?
Phosphate groups, guanine, and cytosine
In figure 13-3, which amino acid is specified by the mRNA code CCC?
Pro
In figure 13-6, A, B, and C are three types of___________
RNA molecules
What is produced during transcription?
RNA molecules
During transcription, ____________ binds to DNA and assembles nucleotides into a strand that is complementary to the DNA template
RNA polymerase
In RNA, _________ is the sugar in the nucloetide
Ribose
RNA contains the sugar
Ribose
The codon that signals the end of a growing polypeptide is called a _____________.
Stop codon
Suppose that part of an amino acid sequence of a protein changed from tyrosine - proline - glycine - alanine to tyrosine - histidine - glycine - alanine. This change was most likely caused by a point mutation called a __________.
Substitution
What happens during translation?
The cell uses a messenger RNA code to make proteins
What does figure 13-2 show?
The genetic code
Where do transcription and translation take place in eukaryotes?
Transcription takes place in the nucleus, and translation takes place in the cytoplasm
A translocation mutation is seen in line D of figure 13 -5
True
DNA molecules stay in the nucleus; RNA molecules leave the nucleus and move through the cytoplasm to the ribosomes
True
The three types of RNA are messenger RNA, transfer RNA, and ribosomal RNA
True
According to figure 13-13, which code specifies the same amino acid as UAU?
UAC
Which nucleotide is different between RNA and DNA
Uracil is used in place of thymine
When is a protein being assembled?
When RNA is being translated