#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.
#Question id: 19090
#Unit 6. System Physiology – Plant
#Question id: 2215
#Unit 2. Cellular Organization
Which statement describes the mode of action of the ABCB1 transporter (the first eukaryotic ABC transporter to be recognized)?
#Question id: 26877
#Unit 10. Ecological Principles
How the Plant species richness with field age is related
#Question id: 11810
#Unit 6. System Physiology – Plant
An experiment was done to see the effect of auxin: cytokinin ratios on morphogenesis can also be seen in crown gall tumors by mutation of the T-DNA of the Agrobacterium Ti plasmid,
I) Mutating the ipt gene (the tmr locus) of the Ti plasmid blocks zeatin biosynthesis in the infected cells
II) mutating either of the genes for auxin biosynthesis (tms locus)
Given some results about these above mutations ,
a) equal auxin to cytokinin ratio form undifferentiated callus tissue
b) high auxin:cytokinin ratio in the tumor cells causes the proliferation of roots instead of undifferentiated callus tissue
c) lowers the auxin:cytokinin ratio and stimulates the proliferation of shoots
What would be the result of these two mutation ?