1. It contains chromatin fibres, which are made up of DNA (Deoxyribonucleic acid). After cell division takes place, these chromatin fibres undergo certain structural changes, and are called chromosomes. These chromosomes carry the hereditary information of the genes.   Hint First letter clue   2. It is semi-permeable, allowing substances to enter and leave the nucleus of the cell. It also provides protection to the nucleus of the cell.   First letter clue   3. It initiates and regulates cell division. It also helps in forming spindle fibres, with the help of asters.   First letter clue   4. It is known as the 'site of protein synthesis in the cell', and synthesizes proteins. It is chiefly composed of RNA (Ribonucleic acid).   First letter clue   5. It is the site of ATP (Adenosine triphosphate) synthesis. It also synthesizes respiratory enzymes.   First letter clue   6. It is the house of all metabolic activities and functions in the cell. In other words, it contains most of the cell organelles, each of which perform a specific function.   First letter clue   7. It helps in the storage of water and several other substances, namely food, waste products and pigments. It also provides turgidity to the cell.   Hint