In a typical angiosperm, what is the sequence of structures encountered by the tip of a growing pollen tube on its way to the egg? 

1. micropyle 2. style 

3. ovary 4. stigma 

TLS Online TPP Program

#Question id: 18963

#Unit 13. Methods in Biology

The use of wild type pTi as a vector presents the following three problems.

1. Presence of oncogenes (iaaM, iaaH and ipt) in T-DNA, which causes a disorganised growth and a loss of regeneration potentiaLof the cells having T-DNA in their genomes.

2. Their large size makes the handling procedures during cloning tedious and cumbersome.

3. A general lack of unique cloning sites within the T-DNA, which are needed for the insertion of DNA segments to be cloned

In the above mention’s problems, 1 and 3 can removed by disarming and creating MCS, to overcome from 2nd problem need to develop

TLS Online TPP Program

#Question id: 18964

#Unit 13. Methods in Biology

Size of agrobacterium can be reduced by binary vector formation; these binary vectors can be formed by phenomenon of

TLS Online TPP Program

#Question id: 18978

#Unit 13. Methods in Biology

For expression vector 

TLS Online TPP Program

#Question id: 18979

#Unit 13. Methods in Biology

For expression vector Strong and Regulatable Promoters are used which have

TLS Online TPP Program

#Question id: 18980

#Unit 13. Methods in Biology

The most widely used strong regulatable promoters are those

TLS Online TPP Program

#Question id: 18981

#Unit 13. Methods in Biology

The pL promoter is controlled by the cl repressor protein of bacteriophage A. In practice, a temperature-sensitive mutant of the cl repressor, cl857, is generally used to regulate pL-directed transcription. Cells carrying the temperature-sensitive cl repressor are first grown at 30°C, and 42°C