TLS Online TPP Program

#Question id: 4104


Consider following statements for catalytic mechanism of RNA polymerase

A. RNA synthesis by RNA polymerase. The reaction involves two Mg2+ ions, coordinated to the phosphate groups of the incoming nucleoside triphosphates (NTPs)

B. Three Asp residues, which are highly conserved in the RNA polymerases of all species. One Mg2+ ion facilitates attack by the 39-hydroxyl group on the phosphate of the NTP; the other Mg2+ ion facilitates displacement of the pyrophosphate, and both metal ions stabilize the pentacovalent transition state.

C. About 17 bp of DNA are unwound at any given time. RNA polymerase and the transcription bubble move from left to right along the DNA as shown, facilitating RNA synthesis. Movement of an RNA polymerase along DNA tends to create negative supercoils (overwound DNA) ahead of the transcription bubble and positive supercoils (underwound DNA) behind it.

D. The RNA polymerase is in close contact with the DNA ahead of the transcription bubble as well as with the separated DNA strands and the RNA within and immediately behind the bubble. A channel in the protein funnels new NTPs to the polymerase active site. The polymerase footprint encompasses about 35 bp of DNA during elongation.

#Unit 3. Fundamental Processes
  1. A & B only        

  2. A, B, C  

  3. A, & C           

  4. B & C only

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TLS Online TPP Program

#Question id: 4827

#Unit 8. Inheritance Biology

A cross between individuals with genotypes AaBbX aabb produces the following progeny:

AaBb -  83, aaBb- 21, Aabb-   19,  aa bb -77

Which of the following statements is true?

TLS Online TPP Program

#Question id: 4828

#Unit 8. Inheritance Biology

Consider two pairs of alleles, G/g and H/h, that follow complete dominance inheritance. The initial cross consisted of GG hh males and gg HH females, and the F I female progeny were test crossed with gg hh males to produce 380 Gghh progeny out of 1000 total progeny. What is approximate distance between Gene G and H.

TLS Online TPP Program

#Question id: 4829

#Unit 8. Inheritance Biology

Plant with genotype AaBb is selfed . the two gene are linked and are 50 map units apart. What proportion of progeny will have the genotype aabb?

TLS Online TPP Program

#Question id: 4830

#Unit 8. Inheritance Biology

Blue flower is dominant over white flower and long pollen is dominant over short pollen. A pure line plant with Blue flower and long pollen was cross with white flower and short pollen. F1 plant was allowed to test cross to produced numerous Offspring in following number

Blue flower and long pollen            2000

Blue flower and short pollen             500

White flower and long pollen            500    

White flower and short pollen         2000

What is approximate distance between Flower color gene and pollen length gene?

TLS Online TPP Program

#Question id: 4831

#Unit 8. Inheritance Biology

There are 4 pairs of chromosomes in a Drosophila.The linkage groups present in it are

TLS Online TPP Program

#Question id: 4832

#Unit 8. Inheritance Biology

Percentage of crossing over is more when