bacteria reproduction - lqc 3a

Question 1

binary fission

Answer 1

• bacteria reaches a certain size
• dna is replicated
• old cell wall begins to break down around the middle of the cell
• dna is associated with the cell membrane (mesosomes)
• cell pinches together forming a septum
• two new identical daughter cells are formed
• plasmids often divide at the same time
• time between divisions is the generation time (as little as 20 mins)

Question 2

3 methods of genetic material transfer in bacteria

Answer 2

• transformation
• transduction
• conjugation

Question 3

transformation

Answer 3

• a short piece of dna is released by a donor or the dna is in the environment
• this is actively taken up by a recipient
• the new dna replaces a similar piece of dna in a recipient

Question 4

transduction

Answer 4

• a small amount of dna is transferred from one bacterium to another by a bacteriophage

Question 5

conjugation

Answer 5

• plasmids dna is transferred from one bacterium to another by direct contact
• the donor cell (F+) produces a sex pilus
• a ‘cytoplasmic bridge’ is created to the recipient cell (F-)
• dna is transferred through the pilus