TLS Online TPP Program

#Question id: 15653


You are studying a new strain of E. coli that can utilize the disaccharide melibiose very efficiently. You find that utilization depends on the enzyme melibiase, which is encoded by the gene Mel1. Mel1 is not expressed unless melibiose is present in the growth medium. You have isolated a mutation that causes constitutive melibiase activity, which you designate MelA–. P1 phage mapping experiments using a Tn5 insertion linked to Mel1 show that MelA– is not linked to Mel1. Moreover you find that when an amber suppressor is introduced into a MelA– mutant, normal melibiase regulation is restored. Classify the MelA– mutation on the basis of genetic properties,  make a proposal for the type of regulatory functions affected by the MelA– mutation?

#Unit 13. Methods in Biology
  1. MelA is likely a constitutive regulator of Mel1 expression.
  2. MelA is likely a positive regulator of Mel1 expression.
  3. MelA is likely a negative regulator of Mel1 expression.
  4. MelA is likely a repressive regulator of Mel1 expression.
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TLS Online TPP Program

#Question id: 3495

#Unit 11. Evolution and Behavior

Which one of the following statements is incorrect?

TLS Online TPP Program

#Question id: 3496

#Unit 11. Evolution and Behavior

Which of following favor adaptations for polygynous mating in species?

a. Male competition

b. Female competition

c. Male choice

d. Female choice

TLS Online TPP Program

#Question id: 3497

#Unit 11. Evolution and Behavior

Which of the following is correct statement?

a. Sexual selection should operate more powerfully in polygamous than in monogamous species

b. Polygynous species should have stronger sexual dimorphism than in monogamous species

c. Male competition or male choice favors adaptations to polygynous mating in species

TLS Online TPP Program

#Question id: 3498

#Unit 11. Evolution and Behavior

Assuming 5 offspring of each female, A Female lion with a well-nourished cub gains inclusive fitness by nursing a starving cub of a full sister by 5% loss to herself. What would be value of be benefit in percent (all offspring of recipient female die in case of no nursing)

TLS Online TPP Program

#Question id: 3499

#Unit 11. Evolution and Behavior

In some jacana species, males take care of the eggs and young, and females compete among themselves for territories that contain one to several males. Female jacanas are significantly larger than males. Which of these statements would you predict to be true of this bird species?

a. Male jacana fitness is primarily limited by ability to take care of eggs and raise young.

b. Female jacana fitness is limited by the number of males in her territory with which a female mates.

c. Variation in reproductive success should be greater in male jacanas than in females.

d. Variation in reproductive success should be greater in female jacanas than in males.

e. Males and females have equal variation in reproductive success.

TLS Online TPP Program

#Question id: 3500

#Unit 11. Evolution and Behavior

To call a behavior altruistic, an evolutionary biologist will have to demonstrate that

A) These behavior is decrease the individual fitness of the donor and increases the individual fitness of the recipient

B) These behavior is increases the individual fitness of both the donor and the recipient

C) Overall increase the inclusive fitness of the population

D) These behavior depend on genetic relation

Which of the following above statement is correct?