transport system[10]
8:11 AM
After learning such a great deal about the transport system in plants, let me add on to some other findings on xylem and phloem tubes:
xylem:
- made of dead cells
- thick cell walls
- cell walls made of lignin (a hard cellulose-like substance which gives rigidity to plant tissues)
- impermeable
- cross walls absent
- no cytoplasm
- transport of water and minerals
- carried to leaves
- upward flow
- tissue has fibres
phloem:
- made of living cells
- thin cell walls
- cell walls made of cellulose
- permeable
- has perforated cross walls called sieve plates
- cells lined with cytoplasm strands
- transport of food
- carried to growing parts and storage organs
- upward and downward flow
- tissue has companion cells
Ok, this marks the end of my biology journal. i hope that all of you will take away some valuable knowledge with you after reading my entries. thank you(: