The promoter of the araBAD operon from E. coli is activated in the presence of arabinose and the absence of glucose and directs expression of genes encoding enzymes required for arabinose metabolism. Unlike the cases of lac and gal genes, where a repressor and an activator work together, here two activators work together: AraC and CAP

+ arabinose	AraC binds that sugar and adopts a configuration that allows it to bind DNA as a dimer to the adjacent half-sites, araI1 and araI2
– arabinose	the AraC dimer adopts a different conformation and binds to araO2 and araI1, there is no monomer at site araI2, and so the protein cannot activate the araBAD promoter (araPBAD). This promoter is also controlled by CAP.

TLS Online TPP Program

#Question id: 3457

#Unit 9. Evolution & Diversity of Life Forms

The idea that monogamy is enforced on females by males who guard them against mating with other males known as

TLS Online TPP Program

#Question id: 3458

#Unit 9. Evolution & Diversity of Life Forms

Which of the following examples reflects the concept of optimal foraging?

TLS Online TPP Program

#Question id: 3459

#Unit 9. Evolution & Diversity of Life Forms

A vampire bat sharing blood with another bat that is not its kin is an example of ________.

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#Question id: 3460

#Unit 9. Evolution & Diversity of Life Forms

The many eyes hypothesis suggests prey flock because:

TLS Online TPP Program

#Question id: 3461

#Unit 9. Evolution & Diversity of Life Forms

the most common way that altruism between related individuals evolves and results from

TLS Online TPP Program

#Question id: 3462

#Unit 9. Evolution & Diversity of Life Forms

Which describes brightly colored peacocks mating more frequently than drab peacocks?