BIO301 Final Term Solved Papers

Q3. enlish variations ocure due to change in chromosome

Numerical changes

➢Aneuploidy

Hypo ploidy Hyper ploidy ➢Euploidy Monoploidy

Diploidy Polyploidy

Structural

➢Translocations

➢Deletions

➢Duplications

➢Inversions

Different cell lines

➢Mosaicism

Q4. What is epigenetics

the study of changes in organisms caused by modification of gene expression rather than alteration of the genetic code itself.

Five complications in inhertianc patteren [check lecture no.157] How mutation alter gene function[check lecture No. 136]

SUBJECTIVE 40 MARKS

Q5. Write the modification of epi genetics ? 10

Epigenetic modifications are crucial for packaging and interpreting the genome under the influence of physiological factors [4-8]. Epigenetics is one of the fastest-growing areas of science and has now become a central issue in biological studies of development and disease [3, 7-11]. In recent years, there have been rapid advancees in the understanding of epigenetic mechanisms [12-14], which include histone modifications [4-6, 15], DNA methylation [10, 11, 16, 18], small and non-coding RNAs [20, 56], and chromatin architecture [13, 15, 21]. These mechanisms, in addition to other transcriptional regulationary events [15, 17], ultimately regulate gene activity and expression during development and differentiation, or in response to environmental stimuli [16, 17].

Epigenetic research can help explain how cells carrying identical DNA differentiate into different cell types, and how they maintain differentiated cellular states [14, 17]. Epigenetics is thus considered a bridge between genotype and phenotype [1-3, 7, 9].

While epigenetics refers to the changes of single genes or sets of genes, the term epigenome reflects the overall epigenetic state of a cell, and refers to global analyses of epigenetic markers across the entire genome [3, 14]. It is therefore critically important to map the epigenetic modification patterns or profile the epigenome in a given cell, which then can be used as epigenetic biomarkers for clinical prediction, diagnosis, and therapeutic development [8, 11, 18, 45]. International human epigenome projects are currently working to catalog all the epigenetic markers in all major tissues across the entire genome. The resulting reference maps will usher in epigenetics as an exciting new era of medical science [14]. As an example of the research community's commitment to classifying epigenetic markers, the National Institutes of Health (NIH) has recently launched a $190 million research effort to learn more about epigenetics.

This mini-review focuses on DNA methylation and the predominant histone modifications, with emphasis on their dynamic interactions within the chromatin environment to form the complex epigenetic mechanisms that orchestrate the regulation of genes at the molecular level in mammalian cells.