Given below are a few statements on Agrobacterium mediated transformation of plants. Which one of the following statements is CORRECT?

• T-DNA transfer occurs from left border to right border

• The gfp reporter gene can never be used for selection of transgenic plants

• Transformation frequencies will decrease on overexpression of virulence genes.

• Host plant genes play an important role in influencing transformation frequencies. 

   

Which one of the following assay systems can specifically detect apoptotic cells?

• Tetrazolium dye (MTT) based colorimetric assay 

• FITC – annexin V based FACS analysis

• 51Cr release assay

• Trypan blue exclusion assay

From the various techniques listed below, which one CANNOT be used to precisely map the transcription start-site of a gene?

• S1 Mapping

• Sequencing the region downstream of promoter

•  5’ RACE

• Primer Extension Method

A group of scientists performed an experiment where they artificially fused mouse cells with monkey cells. The resulting fused cells were labelled with fluorescently tagged antibodies against mouse and monkey surface receptor proteins, X and Y respectively. At the time 0 minute just after fusion events, two receptors were confined to their own half in the heterokaryon. However, such surface receptors (X and Y) intermixed on the cell surface after 60 minutes. Which one of the given statements correctly reflects the outcome of the experiment?

• The ptoteins in cytoplasm are in a dynamic state.

• The proteins on the membrane surface are in a dynamic state.

• Surface membrane proteins exchange with the cytosolic proteins.

• Membrane surface proteins are in a static phase.

475.

In order to detect minor variations in antigen concentration, the following procedures were suggested. Which one will likely be the best option? 

• Antigen coated microtitre well → add antibody → add enzyme conjugated secondary antibody → add substrate and measure colour. 

• Antibody coated microtitre well → add antigen →add enzyme conjugated secondary antibody → add substrate and measure colour. 

• Preincubate antigen with fixed amount of antibody → add to antigen coated well → add enzyme conjugated secondary antibody → add substrate and measure colour.

• Preincubate antigen with fixed amount of antibody → add to antibody coated well →add enzyme conjugated secondary antibody → add substrate and measure colour.

• (i), (ii) and (iii)

• (i), (ii) and (iv)

• (i), (iii) and (iv) 

• (ii), (iii) and (iv) 

• use of fluorescent probes specific for organelles. 

• use of organelle specific fluorescent probes followed by microinjection of fluorescent antibodies against organelle specific protein. 

• use of fluorescent probes in permeabilized cells. 

• use of organelle specific fluorescent probes followed by cryoelectron microscopy 

• (a), (b), (c) 

• (a), (c), (d) 

• (b), (d)

• (c), (d) 

• (a), (b), (e), (f), (g)

• (a), (b), (c), (d), (g) 

• (a), (d), (e), (f), (g) 

• (c), (d), (e), (f), (g) 

Which one of the following set of essential components are required for Sanger method of DNA sequencing in a required buffer containing MgCl₂ and Tris-HCl?

• DNA template, a primer, 4 deoxyribonucleotides, 4 labelled dideoxyribonucleotides, DNA polymerase 

• DNA template, a primer, 4 labelled dideoxyribonucleotides, DNA polymerase, DNA ligase 

• DNA template, 4 deoxyribonucleotides, 4 labelled dideoxyribonucleotides, DNA polymerase, DNA ligase.

• DNA template, a primer, 4 labelled dideoxyribonucleotides, DNA polymerase, telomerase.