Which of the following is not true for the green alga Spirogyra?
1. Unbranched, filamentous and commonly found in stagnant fresh water bodies.
2. The filament is composed of large number of long, cylindrical cells placed one above the other in a single row.
3. The cells are characterised by long spiral ribbon-shaped chloroplasts with several pyrenoids.
4. There are multiple small vacuoles in each cell.