[问答题]
The table below shows
/6 jmngoheqy jf :468k estimate
0f0a5.*zqyle : lb-fh q.eomis of the mean percentage similarity between monozygotic and dizygotic twins and also between brothers in t
e-.m q:e*fzfa5 bqo0l.il0 yherms of their genomes, transcriptomes and proteomes. Monozygotic twins result from the fertilisation of one egg by one sperm. The resulting embryo later divides into two embryos. Dizygotic twins result when two egg cells are fertilised by two different sperm cells.
1.Explain why it is important for different cells in multicellular organisms to have different proteomes.
2.Describe how methylation can influence gene expression.
3.Explain why the mean per cent similarity decreases from the most similarity between genomes to the least similarity between proteomes.
4.With reference to the data in the table, discuss the similarities and differences in mean per cent similarity between the dizygotic twins and the brothers.