You have isolated two temperature-sensitive mutations in phage l that you suspect may be in the same gene. These phage mutants are called ts-1 and ts-2. Each mutant will form plaques at 35˚C but not at 42˚C. You cross ts-1 to ts-2 phage by coinfecting E. coli at the permissive temperature of 35˚C. When the resulting phage lysate is plated at 35˚C you count 10,000 plaques per ml of phage lysate, but when the same phage lysate is plated at 42˚C, there are only 80 plaques per ml. Find out the relative order of sm, ts-1 and ts-2?

TLS Online TPP Program

#Question id: 12325

#Unit 10. Ecological Principles

According to bottom-up and top-down control models of community organization, which of the following expressions would  imply  that  an  increase  in  the  size  of  a  carnivore  (C)population  would  negatively  impact  on  its  prey  (P) population, but not vice versa? 

TLS Online TPP Program

#Question id: 12326

#Unit 10. Ecological Principles

Please refer to the following art to answer the following question.

According to the Shannon Diversity Index, which block would show the greatest diversity?

TLS Online TPP Program

#Question id: 12327

#Unit 10. Ecological Principles

Which  of  the  following  is  the  most  accepted hypothesis as  to  why  invasive  species  take  over  communities into which they have been introduced?

TLS Online TPP Program

#Question id: 12328

#Unit 10. Ecological Principles

The dominant species in a community is

TLS Online TPP Program

#Question id: 12329

#Unit 10. Ecological Principles

In a tide pool, 15 species of invertebrates were reduced to eight after one species was removed. The species removed was likely a(n)

TLS Online TPP Program

#Question id: 12330

#Unit 10. Ecological Principles

Elephants are not the most common species in African grasslands. The grasslands contain scattered woody plants, but they are kept in check by the uprooting activities of the elephants. Take away the elephants, and the grasslands convert to forests or to shrublands. The newly growing forests support fewer species than the previous grasslands. Which of the following describes why elephants are the keystone species in this scenario?