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TLS Online TPP Program

#Question id: 13129

Biologists performed an experiment with flies to examine the effects of population size on the maintenance of genetic variation  and  on  egg-to-adult survival.  From  a  large  source  population, they  randomly  assigned  eggs  to  three experimental  populations  of  size  N,  equal  to  20,  60,  and0100.  For  later  generations,  they  collected  N  eggs  from each  population  and  moved  them  into  identical  vials  that  co0ntained  f2re0sh  me4d0ium.  Th6e0y  coun8te0d  the  number  of adult flies that emerged and used tissue samples from the adults for genetic analyses. Genetic variation was measured by  scoring  alleles  at  several  polymorphic  loci  and  expressed  as  the  average  number  of  alleles  at  those  loci.  The results are summarized in Figure 1 and Figure 2 below.

Based on Figure 1, which of the following best describes the change in genetic variation over time? 

#Unit 10. Ecological Principles
  1. It increased in all three populations.
  2. It was unchanged in the largest population and increased in the two smaller populations. 
  3. It was unchanged in all three populations.
  4. It was unchanged in the two larger populations and declined in the smallest population.
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TLS Online TPP Program

#Question id: 28165

#Unit 13. Methods in Biology

Q. Arrange the steps of cloning and selection in YAC vector

a. BamHI digestion creates linear chromosome with telomeric ends.
b. Transformation
c. EcoRI digestion creates two arms, each with a selectable marker (X or Y).
d. Selection on the basis of marker
TLS Online TPP Program

#Question id: 12103

#Unit 10. Ecological Principles

Which of the following is a good description of an ecological niche? 
TLS Online TPP Program

#Question id: 5405

#General Aptitude

The batting average for 25 innings of a cricketer is 52 runs. His highest score differs his lowest score by 144 runs. If these two innings are excluded, the average of the remaining 23 innings is 48 runs. The highest score of the player is
TLS Online TPP Program

#Question id: 29570

#Unit 6. System Physiology – Plant

Bacteria such as Pseudomonas, Xanthomonas, Ralstonia, Erwinia, Pectobacterium Similarities between their bacterial pathogenic island can be estimated by
TLS Online TPP Program

#Question id: 4755

#Unit 8. Inheritance Biology

When two albino snails were crossed, all of the F1 were pigmented. All F1 intercross would results