In a biochemical experiment, you compare the products from splicing reactions carried out in vitro using three different substrates. In each case the substrate is a construct containing a single intron surrounded by two exons, and in all cases the construct is the same overall size. But in one case, the intron is a group I intron, in another a group II intron, and in the third an intron removed by the spliceosome. Each construct is labelled in a manner that allows it to be detected after gel electrophoresis, and each is tested in two reactions—one, conditions that support self-splicing, and two, in the presence of nuclear extract as well. Note that, for simplification, only the final products of the splicing reaction are seen, but before degradation of the introns.

 Which of the following observation is/are correct?

A. In lane A, the presence of nuclear abstract, a band for the lariat and the spliced product and pre-mRNA.

B. Lane B shows Group I Introns and Lane C is for Group II introns and reaction is nonself-splicing

C. Lane C is Group I intron. Splicing takes place in the absence and presence of nuclear abstract, and the reaction is self-splicing.

#Question id: 12192

#Unit 6. System Physiology – Plant

#Question id: 12191

#Unit 6. System Physiology – Plant

#Question id: 11902

#Unit 6. System Physiology – Plant

A chemiosmotic model  has been proposed  to explain Polar transport , following steps are involve in the transport of auxin polarly;

a) IAA enters the cell either passively in the undissociated form (IAAH) or by secondary active cotransport in the anionic form (IAA–)

b) The cell wall is maintained at an acidic pH by the activity of the plasma membrane H+- ATPase

c) In the cytosol, which has acidic pH, the IAAH form predominates

d) The anions exit the cell via auxin anion efflux carriers that are concentrated at the basal ends of each cell in the longitudinal pathway

Which of the following is the correct statements about the polarly transporting of auxin?

#Question id: 11850

#Unit 6. System Physiology – Plant

The first step in polar transport is auxin influx. According to the model, auxin can enter plant cells from any direction by either of two mechanisms:

a) Passive diffusion of the protonated (IAAH) form across the phospholipid bilayer

b) Secondary active transport of the dissociated (IAA–) form via a 2H+–IAA– symporter

c) Active diffusion of the protonated (IAAH) form across the phospholipid bilayer

Find out the correct statements of about diffusion of IAA.

#Question id: 11849

#Unit 6. System Physiology – Plant

According to chemiosmotic model for polar auxin transport, auxin _____A_______is driven by the______B________ across the plasma membrane, while auxin ___C_____is driven by the_________D_________

#Question id: 11848

#Unit 6. System Physiology – Plant

Polar transport is specific for active auxins, such as