Rajya Sabha is a permanent body and is not subject to dissolution. However, one third of the members retire every second year, and are replaced by newly elected members.
The purines are bases in the DNA. The two purines in DNA are Adenine and Guanine. These two purines forms hydrogen bonds with their complimentary pyrimidines such as Thymine and Cytosine to keep the two rails of the DNA molecule together.
Coagulation is a chemical process that involves neutralization of charge. Coagulation during water treatment is designed to remove particles suspended in water.