Genetics, populations, evolution and ecosystems

Question 1

Genetic mutations
- Insertion

Answer 1

• Causes a frameshift
• When a nucleotide is randomly
  inserted into DNA sequence
• Affects function of polypeptide

Cause Huntignton’s Disease

Question 2

Genetic mutations
- Substitution

Answer 2

• Where a DNA base/ nucleotide is swapped for a different one
• Silent substitution alters amino acid sequence
• Missense substitution alters single amino acid
• Nonsense substitution creates a premature stop codon

Cause Sickle Cell Anemia

Question 3

Genetic mutations
- Deletion

Answer 3

• Causes a frameshift
• A nucleotide is randomly deleted
• Affects function of polypeptide

Cause Cystic Fibrosis

Question 4

Genetic mutations
- Inversion

Answer 4

• A single gene is cut into 2 pieces, inverted 180° and rejoined
• Results in non functional protein

Cause Haemophilia A

Question 5

Genetic mutations
- Duplication

Answer 5

• One or more bases are duplicated in the DNA sequence
• Original gene is not changed

Cause Charcot- Marte Tooth Disease

Question 6

Genetic mutations
- Translocation

Answer 6

• A section of a chromosome is added to another chromosome which is not its homologous partner
• Philadelphia chromosome (22) found in Leukemia Cancer

Cause Cancer, Infertility and Down Syndrome