Blind spot  There are no visual receptors over the optic disk

TLS Online TPP Program

#Id: 2648

#Unit 13. Methods in Biology

Primer extension, S1 mapping, and Northern blotting are useful for determining the concentrations of specific transcripts in a cell at a given time, but they do not necessarily tell us the rates of synthesis of the transcripts.

TLS Online TPP Program

#Id: 2735

#Unit 13. Methods in Biology

In Run-on transcription- the RNA polymerase that has already initiated transcription in vivo simply “runs on” or continues to elongate the same RNA chains. 

TLS Online TPP Program

#Id: 2736

#Unit 13. Methods in Biology

The run-on reaction is usually done in the presence of labeled nucleotides so the products will be labeled.

TLS Online TPP Program

#Id: 2737

#Unit 13. Methods in Biology

Nuclear run-on transcription is a way of ascertaining which genes are active in a given cell by allowing transcription of these genes to continue in isolated nuclei.

TLS Online TPP Program

#Id: 2738

#Unit 13. Methods in Biology

The run-on assay can also be used to determine the effects of assay conditions on nuclear transcription.

TLS Online TPP Program

#Id: 2739

#Unit 13. Methods in Biology

To measure the activity of a promoter, one can link it to a reporter gene, such as the genes encoding b-galactosidase, CAT, or luciferase, and let 

the easily assayed reporter gene products indicate the activity of the promoter.