You are interested in a new type of autosomal dominant mutation that gives purple eyes in Drosophila. You have a true-breeding purple-eyed line carrying a mutation that you call pr-1. You have isolated a second purple-eyed mutation that you call pr-2, which you have established in a true-breeding line that also carries a recessive marker st, which gives stubby legs. You cross a fly from the pr-1 line to a fly from the st, pr-2 line producing F1 females which you then cross to males from a true breeding st line (normal eyes). From this cross, 1000 progeny flies can be categorized into four different phenotypic classes:

                      

What is the relative order of st, pr-1 and pr-2?

#Question id: 26978

#Unit 10. Ecological Principles

If the organism have survival of juveniles and adult is poor, selection pressure favors in these organisms

#Question id: 26979

#Unit 10. Ecological Principles

If the organism have survival of juveniles and adult is poor, selection pressure favors in these organisms

#Question id: 26980

#Unit 10. Ecological Principles

Which of the following statements about the selection pressure is incorrect?

a.If survival of juveniles and adult is poor then selection favours a single act of reproduction

b.If survival of juveniles and adult is poor and unpredictable then selection favours repeated reproduction and long reproductive life

c.If the environment is stable then selection favours a single act of reproduction.

d.If survival of juveniles is very poor and unpredictable but adult are more likely to survive then selection favours repeated reproduction and long reproductive life

e.If survival of adult is unpredictable but juveniles are more likely to survive then selection favours a single act of reproduction

#Question id: 26981

#Unit 10. Ecological Principles

Life history features of r-selected species is

#Question id: 26982

#Unit 10. Ecological Principles

Which of the following statements about the evolution of life histories is correct?

a.Unstable environments with unlimited resources favor r-selected populations.

b.K-selected populations are most often found in environments where density-independent factors are important regulators of population size.

c.Most populations have both r- and K-selected characteristics that vary under different environmental conditions.

d.The reproductive efforts of r-selected populations are directed at producing just a few offspring with good competitive abilities.

#Question id: 26983

#Unit 10. Ecological Principles