#Question id: 28431
#Unit 5. Developmental Biology
Which of the following cells direct the movement of the primitive streak in avian development?
#Question id: 12901
#General Aptitude
#Question id: 2299
#Unit 2. Cellular Organization
_______ are plastids containing carotenoid pigments, and _______ are plastids containing starches.
#Question id: 18700
#Unit 13. Methods in Biology
#Question id: 2902
#Unit 2. Cellular Organization
The function and positioning of the histone variants can be studied by an application of technologies used in genomics. One useful technology is chromatin immunoprecipitation, or chromatin IP (ChIP). The correct sequence of the processes that occur in this experiment will be?
1. A histone variant with an epitope tag is introduced into a particular cell type, where it is incorporated into nucleosomes.
2. The pattern of hybridization on the microarray reveals the DNA sequences bound by the nucleosomes with the histone variant.
3. Antibody is added, and the nucleosomes containing the epitope-tagged histone variant are selectively precipitated.
4. Chromatin is isolated from the cells and digested briefly with micrococcal nuclease (MNase).
5. The DNA in these nucleosomes is extracted from the precipitate, labeled, and used to probe a microarray representing all or part of the genomic sequences of that particular cell type.