DNA Mutations Practice Worksheet with Answer Key - an educational resource for learning about genetic mutations and their effects.
DNA Mutations Practice Worksheet with Answer Key, featuring educational content on gene mutations, types of mutations, and genetic sequences.
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Step-by-step solution for: DNA Mutations Practice Worksheet With Answer Key - Laney Lee
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Show Answer Key & Explanations
Step-by-step solution for: DNA Mutations Practice Worksheet With Answer Key - Laney Lee
1. A mutation is any change in a DNA sequence. Sometimes mutations cause random error or mistake as the cell goes through its usual processes. It can occur at several points in the cell cycle. One possibility is that DNA correctly during replication. Another chance for mutation is during meiosis when sister chromatids split apart in opposite poles. Nondisjunction is the other possibility as not separate properly. During mitosis, during meiosis, pieces of homologous chromosomes trade place. This is a piece of the chromosome that is lost.
2. Mutations are "silent" because they do not change the amino acid sequence of the protein. The genetic code is degenerate, meaning multiple codons can code for the same amino acid. If a substitution mutation results in a codon that codes for the same amino acid, the protein structure and function remain unchanged.
3. A substitution mutation that completely stops the translation is called a nonsense mutation. This occurs when a point mutation changes a codon that codes for an amino acid into a stop codon (UAA, UAG, or UGA), causing premature termination of protein synthesis.
4. Insertion and deletion mutations are known as "frameshift mutations" because they alter the reading frame of the codons. Since codons are read in groups of three nucleotides, adding or removing nucleotides that are not in multiples of three shifts the grouping, changing every subsequent codon and usually resulting in a nonfunctional protein.
5. Mutations will be passed on to future generations only if they occur in germ-line cells (sperm or egg cells). Mutations in somatic (body) cells affect only the individual and are not inherited by offspring.
6. True/False: All mutations are bad. Explain your answer.
- False. Not all mutations are harmful. Some mutations are neutral, having no effect on the organism's fitness. Others can be beneficial, providing an advantage in certain environments (e.g., antibiotic resistance in bacteria, lactose tolerance in humans).
7. True/False: Mutations can be passed from parent to child. Explain your answer.
- True. Mutations that occur in the germ-line cells (gametes) can be inherited by offspring. These are called heritable mutations. Mutations in somatic cells are not passed on.
8. Label each of the following chromosome mutations:
- Top left: Deletion (a segment of the chromosome is missing)
- Top right: Duplication (a segment of the chromosome is repeated)
- Bottom left: Inversion (a segment of the chromosome is reversed)
- Bottom right: Translocation (a segment of one chromosome is attached to another non-homologous chromosome)
9. Match the words with their definition:
1. Mutation - D. An error in DNA
2. Mitosis - L. Division of body cells
3. Crossing Over - J. Exchange of genetic material between homologous chromosomes
4. Meiosis - K. Division of sex cells
5. Nucleotide - F. Building block of DNA
6. Missense Mutation - G. Changes one amino acid to another
7. Amino Acid - I. Building block of proteins
8. Codon - H. Three nucleotides that code for one amino acid
9. Gene - C. Segment of DNA that codes for a specific protein
10. Non-disjunction - M. Failure of chromosomes to separate during meiosis
11. Gene Mutation - A. Change in a single gene
12. Insertion - B. Addition of one or more nucleotides
13. Substitution - E. Replacement of one nucleotide with another
14. Deletion - N. Removal of one or more nucleotides
15. Silent Mutation - O. Does not change the amino acid sequence
16. Meiosis - K. Division of sex cells
17. Chromosome - P. Structure made of DNA and proteins
18. Mutation - D. An error in DNA
19. Nonsense Mutation - Q. Creates a premature stop codon
20. Frameshift Mutation - R. Alters the reading frame
21. Inversion - S. Reversal of a chromosome segment
22. Translocation - T. Movement of a chromosome segment to another chromosome
23. Duplication - U. Repetition of a chromosome segment
24. Variation - V. Differences among individuals of a species
25. Disorder - W. Condition that disrupts normal body function
10. Compare the mutated DNA with the original strand. Determine what kind of gene mutation occurred.
- Original DNA: ATG CAT TCA GGC A
mRNA: UAC GUA AGU CCG U
Amino Acids: Tyr-Val-Ser-Pro
- Mutated DNA #1: ATG CAT TCA GGC A
mRNA: UAC GUA AGU CCG U
Amino Acids: Tyr-Val-Ser-Pro
Type of Mutation: None (identical to original)
- Mutated DNA #2: ATG CAT TCA TAG GC
mRNA: UAC GUA AGU AUC CG
Amino Acids: Tyr-Val-Ser-Ile
Type of Mutation: Deletion (one nucleotide deleted, frameshift)
- Mutated DNA #3: ATG TAT TCA GGC A
mRNA: UAC AUA AGU CCG U
Amino Acids: Tyr-Ile-Ser-Pro
Type of Mutation: Substitution (C changed to T, missense)
- Mutated DNA #4: ATG CAT TAG GCA T
mRNA: UAC GUA AUC CGU A
Amino Acids: Tyr-Val-Ile-Arg
Type of Mutation: Insertion (one nucleotide inserted, frameshift)
2. Mutations are "silent" because they do not change the amino acid sequence of the protein. The genetic code is degenerate, meaning multiple codons can code for the same amino acid. If a substitution mutation results in a codon that codes for the same amino acid, the protein structure and function remain unchanged.
3. A substitution mutation that completely stops the translation is called a nonsense mutation. This occurs when a point mutation changes a codon that codes for an amino acid into a stop codon (UAA, UAG, or UGA), causing premature termination of protein synthesis.
4. Insertion and deletion mutations are known as "frameshift mutations" because they alter the reading frame of the codons. Since codons are read in groups of three nucleotides, adding or removing nucleotides that are not in multiples of three shifts the grouping, changing every subsequent codon and usually resulting in a nonfunctional protein.
5. Mutations will be passed on to future generations only if they occur in germ-line cells (sperm or egg cells). Mutations in somatic (body) cells affect only the individual and are not inherited by offspring.
6. True/False: All mutations are bad. Explain your answer.
- False. Not all mutations are harmful. Some mutations are neutral, having no effect on the organism's fitness. Others can be beneficial, providing an advantage in certain environments (e.g., antibiotic resistance in bacteria, lactose tolerance in humans).
7. True/False: Mutations can be passed from parent to child. Explain your answer.
- True. Mutations that occur in the germ-line cells (gametes) can be inherited by offspring. These are called heritable mutations. Mutations in somatic cells are not passed on.
8. Label each of the following chromosome mutations:
- Top left: Deletion (a segment of the chromosome is missing)
- Top right: Duplication (a segment of the chromosome is repeated)
- Bottom left: Inversion (a segment of the chromosome is reversed)
- Bottom right: Translocation (a segment of one chromosome is attached to another non-homologous chromosome)
9. Match the words with their definition:
1. Mutation - D. An error in DNA
2. Mitosis - L. Division of body cells
3. Crossing Over - J. Exchange of genetic material between homologous chromosomes
4. Meiosis - K. Division of sex cells
5. Nucleotide - F. Building block of DNA
6. Missense Mutation - G. Changes one amino acid to another
7. Amino Acid - I. Building block of proteins
8. Codon - H. Three nucleotides that code for one amino acid
9. Gene - C. Segment of DNA that codes for a specific protein
10. Non-disjunction - M. Failure of chromosomes to separate during meiosis
11. Gene Mutation - A. Change in a single gene
12. Insertion - B. Addition of one or more nucleotides
13. Substitution - E. Replacement of one nucleotide with another
14. Deletion - N. Removal of one or more nucleotides
15. Silent Mutation - O. Does not change the amino acid sequence
16. Meiosis - K. Division of sex cells
17. Chromosome - P. Structure made of DNA and proteins
18. Mutation - D. An error in DNA
19. Nonsense Mutation - Q. Creates a premature stop codon
20. Frameshift Mutation - R. Alters the reading frame
21. Inversion - S. Reversal of a chromosome segment
22. Translocation - T. Movement of a chromosome segment to another chromosome
23. Duplication - U. Repetition of a chromosome segment
24. Variation - V. Differences among individuals of a species
25. Disorder - W. Condition that disrupts normal body function
10. Compare the mutated DNA with the original strand. Determine what kind of gene mutation occurred.
- Original DNA: ATG CAT TCA GGC A
mRNA: UAC GUA AGU CCG U
Amino Acids: Tyr-Val-Ser-Pro
- Mutated DNA #1: ATG CAT TCA GGC A
mRNA: UAC GUA AGU CCG U
Amino Acids: Tyr-Val-Ser-Pro
Type of Mutation: None (identical to original)
- Mutated DNA #2: ATG CAT TCA TAG GC
mRNA: UAC GUA AGU AUC CG
Amino Acids: Tyr-Val-Ser-Ile
Type of Mutation: Deletion (one nucleotide deleted, frameshift)
- Mutated DNA #3: ATG TAT TCA GGC A
mRNA: UAC AUA AGU CCG U
Amino Acids: Tyr-Ile-Ser-Pro
Type of Mutation: Substitution (C changed to T, missense)
- Mutated DNA #4: ATG CAT TAG GCA T
mRNA: UAC GUA AUC CGU A
Amino Acids: Tyr-Val-Ile-Arg
Type of Mutation: Insertion (one nucleotide inserted, frameshift)
Parent Tip: Review the logic above to help your child master the concept of mutations practice worksheet.
