Wild type E. coli metabolizes the sugar lactose by expressing the enzyme ß-galactosidase. You have isolated a mutant that you call lac1–, which cannot synthesize ß-galactosidase and cannot grow on lactose (Lac–). During an condition Lac– strain, called lac3–, is linked to the Tn5 insertion. From a strain carrying the Tn5 insertion and lac3– mutation you isolate an F’ that caries a region of the chromosome that includes both Tn5 and the linked Lac region. Introduce this F’ into an F– strain carrying lac1– by selecting for Kanr. These merodiploids express ß-galactosidase normally. What does this result tell you about the relationship between the lac3– and lac1- mutations?  

#Question id: 10688

#Unit 10. Ecological Principles

For two species A and B in competition, the carrying capacities, competition coefficients, per capita growth rate and population size are

KA = 1000           KB = 1200    α of B= 1     β of A= .5       rB= .5         r A= .3                

AN= 500                  BN= 200

According to the Lotka-Volterra model, what is growth rate of species A?

#Question id: 10689

#Unit 10. Ecological Principles

Which of the following is correct statement?

A) Body size of parasitoid is always greater than host but parasite usually smaller than host

B) Predator immediately kill their prey however parasitoid never kill their host

C) Intrinsic rate of parasite is faster than host but intrinsic rate of predator is slower than prey

D) Body association time between parasite and host is more than time association between predator and prey

#Question id: 10690

#Unit 10. Ecological Principles

Which of following interaction shown in following species of Paramecium?

#Question id: 10691

#Unit 10. Ecological Principles

Following some attributes of biological control agent of parasite

A) General adaptability to the environment.

B) High searching capacity for hosts.

C) K selected strategy

D) Low dispersal ability.

E) Minimal time lag effects in responding to changes in host numbers.

Following above attribute is not ideal for that biological agent?

#Question id: 10692

#Unit 10. Ecological Principles

#Question id: 10693

#Unit 10. Ecological Principles

The diagram represents competition between species 1 and species 2 according to Lotka-Volterra model of competition

Given the conditions in the diagram, the predicted outcome of competition is