21. MUTATIONS

Question 1

1. What are Mutations?

Answer 1

• they are nucleotide sequence changes
• they may become permanent
• they can then be passed onto the next generation

Question 2

2. What are Mutations a source of?

Answer 2

• they are a source of genetic variation
• upon which natural selection operates

Question 3

3. What types of Mutations can we have?

Answer 3

1. HARMFUL MUTATIONS
   
   • EG: carcinogenic ones
2. BENEFICIAL MUTATIONS
   
   • these are usually favoured by natural selection
   • EG: Sickle Cell Anaemia carriers have an immunity to
     Malaria
3. NEITHER HARMFUL NOR BENEFICIAL
   
   • these are known as silent mutations

Question 4

4. Read over this table.
   Does everything make sense?

Answer 4

• yes

Question 5

5. What happens if one repair mechanism fails?

Answer 5

• another repair mechanism that repairs the exact same
  thing can take over

Question 6

6. Read over this summary.
   Does everything make sense?

Answer 6

• yes

Question 7

7. Answer this SBA.

Answer 7

• B
• it is found in all species