Cells. : Give reasons
1. Plant cells are more rigid than animal cells. 2. Cells are the basic structural unit of living organisms. 3. Tomatoes are red in colour. 4. More mitochondria is present in cells engaged in more physiological activities. 5. Nucleus is control centre of cell. 6. Mitochondria is powerhouse of the cell. 7. Plastids are found only in plant cells. 8. Plant cells have big vacoules. 9. Shape of the cells differ in multicellular organisms. 10. The cells remained undiscovered for a long time.