Definitions

Across

• 1. The model of cell membrane structure proposed by Singer and Nicholson – a phospholipid bilayer with proteins ‘floating’ in it. (5, 6, 5)
• 5. An organelle found in plants, which contains chlorophyll and is responsible for photosynthetic activity in the plant. (11)
• 6. Nuclear Division that results in the formations of cells that are genetically identical to the parent cell. (7)
• 7. A water proofing substance that impregrenates the walls of the xylem tissue. Ligin gives wood to its strength. (5)
• 8. A cell in the phloem involved in actively loading sucrose into the sieve tube elements. The companion cell is closely associated with a phloem sieve element, to which it is linked by many plasmodesmata. (9, 4)
• 9. An attractive between substances or particles. (8)
• 10. A chemical system that resists changes in pH by maintaining a constant level of hydrogen ions in solution. Certain chemicals dissolved in the solution are responsible for this (6)