Time remaining:
Describe Andersson and Hughes' study of Muller's ratchet in bacteria.

Biology
Tutor: None Selected Time limit: 0 Hours

Describe Andersson and Hughes' study of Muller's ratchet in bacteria. What features of their populations might have increased the effect of Muller's ratchet?

Oct 31st, 2014

  Andersson and Miller allowed 444 cultures of bacteria to grow for two months, with one bottleneck every day during which each culture was reduced to a single individual. The combination of asexual reproduction with frequent population bottlenecks was expected to cause Muller's ratchet to operate, i.e., accumulation of deleterious mutations and consequently reduced fitness. At the end of the two months, representing roughly 1700 generations and roughly 60 bottlenecks, all cultures were compared to the wild-type strain. 5% of the experimental cultures had reduced fitness (reduced growth rate) and none had increased fitness, so the result was consistent with Muller's ratchet. But since, Muller's ratchet takes a very large number of generations to have an appreciable effect - and even then the effect is small - it is not thought to be the major process favoring sexual reproduction

Reference:

www.life.umd.edu/biology/.../Exam%202%20Study%20Questions%20(c...


Oct 31st, 2014

Did you know? You can earn $20 for every friend you invite to Studypool!
Click here to
Refer a Friend
...
Oct 31st, 2014
...
Oct 31st, 2014
Feb 22nd, 2017
check_circle
Mark as Final Answer
check_circle
Unmark as Final Answer
check_circle
Final Answer

Secure Information

Content will be erased after question is completed.

check_circle
Final Answer