Lecture 37. Bacterial Evolution

Question 1

What did Lamarckian evolution state?

Answer 1

Life is not fixed - if an organism uses something more it will increase, if not uses it will shrink. Change is determined by the environment

Question 2

What did Darwinian evolution state?

Answer 2

Change is spontaneous - natural selection ensures survival of the fittest/ The change is random then selected

Question 3

When was Darwinian evolution accepted by the majority of scientists?

Answer 3

Mid 20th century

Question 4

What were the two reasons why there were exemptions in the scientific community on accepting Darwinian evolution?

Answer 4

Lysenkoism: Political interference in science (ideology over facts)
Prokaryotes: Lack of data to support theory

Question 5

Luria-Delbrück experiment observation

Answer 5

Add a toxic agent to bacterial culture and the entire culture becomes resistant

Question 6

Luria-Delbrück experiment interpretation

Answer 6

The agent makes the cells resistant

Question 7

Luria-Delbrück experiment conclusion

Answer 7

Bacteria unlike higher organisms follow Lamarckian evolution

Question 8

How was the Luria-Delbrück experiment carried out?

Answer 8

E. coli cultures were grown
Aliquots plated on plates containing T1 phage
T1 phage kills E. coli

Question 9

What did the result of Newcombe’s experiment show?

Answer 9

More colonies on re-spread plate