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? 

#Question id: 4120

#Unit 3. Fundamental Processes

Which of the following homolog matching is incorrectly matched with thier respective subunits?

#Question id: 4119

#Unit 3. Fundamental Processes

Many eukaryotic genes contain a large number of exons. Correct splicing of such genes requires that neighboring exons be ligated to one another; if they are not, exons will be left out. One early proposal suggested that the splicing machinery bound to a splice site at one end of an intron and scanned through the intron to find the splice site at the other end. Such a scanning mechanism would guarantee that an exon was never skipped. This hypothesis was tested with one minigene with a duplicated 5ʹ splice site. Find diagram of the products you expect from minigene if the splicing machinery binds to a 5ʹ splice site and scans toward a 3ʹ splice site.

#Question id: 4118

#Unit 3. Fundamental Processes

If the 5’ splice site sequence changed from 5’- GUAAGU-3’ to 5’-GUAUGU-3’, predict the effect of the sequence change on U1 binding and U6 snRNP binding in an in vitro protein– RNA binding assay.

#Question id: 4117

#Unit 3. Fundamental Processes

The RNA recognition motif (RRM), also called the RNP motif and the RNA-binding domain (RBD), is the most common RNA-binding domain in hnRNP proteins. Choose important characteristics of RBD

a. RRM domain consists of a four-stranded b sheet flanked on one side by two a helices.

b. To interact with the negatively charged RNA phosphates, the b sheet forms a positively charged surface

c. The 45-residue KH motif is also found in the hnRNP and several other RNA-binding proteins

Which of the following statements are correct?

#Question id: 4116

#Unit 3. Fundamental Processes

Proteins that regulate splicing bind to specific sites called exonic (or intronic) splicing enhancers (ESE or ISE) or silencers (ESS and ISS). The former enhances, and the latter repress, splicing at nearby splice sites. Examples of splicing activator and repressors are as

#Question id: 4115

#Unit 3. Fundamental Processes

The possible type of splicing outcome of given gene construct will be