DNA Mutations
What is a DNA mutation?
a change in a DNA sequence
What is protein synthesis?
A. the process of breaking down proteins
B. the process of making proteins using genetic information
C. the process of copying RNA into DNA
D. the process of breaking down DNA
B. the process of making proteins using genetic information
What is transcription?
A. the process of making proteins
B. the process of copying RNA into DNA
C. the process of copying DNA into RNA
D. the process of breaking down RNA
C. the process of copying DNA into RNA
What is translation?
A. copying DNA into RNA
B. making RNA in the nucleus
C. using mRNA to build a protein
D. breaking down proteins
C. using mRNA to build a protein
Original DNA: ATG CCT GAA
Mutated DNA: ATG CAT GAA
What kind of mutation is this? How do you know?
Substitution because the base cytosine (C) has been substituted for adenine (A)
Which molecule carries genetic instructions from DNA to the ribosomes?
A. tRNA
B. rRNA
C. mRNA
D. DNA
C. mRNA
Which based pairing rule is used during transcription?
A. A-T and C-G
B. A-U and C-G
C. A-C and G-U
D. T-U and C-A
B. A-U and C-G
Why is translation important?
A. it creates DNA
B. it produces DNA
C. it allows cells to make proteins
D. it breaks down nutrients
C. it allows cells to make proteins
Original DNA: ATG CCT GAA
Mutated DNA: ATG CCG TGA A
What kind of mutation is this? How do you know?
Insertion because the base guanine (G) has been inserted, causing the mutated DNA sequence to become longer
A codon is:
A. a sequence of three amino acids
B. a sequence of three nucleotides on mRNA
C. a type of protein
D. a ribosome structure
B. a sequence of three nucleotides on mRNA
Transcribe the following DNA sequence:
TAC GGC AAT TCG
AUG CCG UUA AGC
Translate each codon into an amino acid:
AUG CCG AUA GAA UAA
met- pro- ile- glu- stop
Original DNA: ATG CCT GAA
Mutated DNA: ATG CTG AA
What kind of mutation is this? How do you know?
Deletion because the base cytosine (C) is missing from the mutated sequence, causing the mutated sequence to become shorter
Which of the following is the correct order of protein synthesis?
A. translation --> transcription --> protein
B. DNA --> RNA --> protein
C. RNA --> DNA --> protein
D. protein --> RNA --> DNA
B. DNA --> RNA --> protein
Transcribe the following DNA sequence:
TAC TTT CGA GAA
AUG AAA GCU CUU
Translate each codon into an amino acid:
AUG AAA CGU GGC UUU UGA
met- lys- arg- gly- phe- stop
Write your own original and mutated DNA sequence. Identify the type of mutation and explain. (3 minutes)
answers may vary. only bases A,T,G,C are used. NOT uracil (U)
What determines the sequence of amino acids in a protein?
A. the shape of the ribosome
B. the type of cell
C. the number of ribosomes
D. the order of bases in DNA
D. the order of bases in DNA
Transcribe the following DNA sequence:
TAC GAA TCG ACT
AUG CUU AGC UGA
Explain how a change in the DNA sequence can lead to a change in the protein. (5 min)
Be sure to include the following:
how DNA is transcribed into mRNA
how mRNA is translated into amino acids
how a change in the amino acid sequence can change the protein's structure or function
When a DNA mutation is present, the mRNA codons are changed. This leads to different amino acids during translation. If the mutated amino acid sequence is not in the same order as the original amino acid sequence, then the protein will be changed, affecting its shape or function.