Phloem
Definition
Phloem is the vascular tissue that transports organic nutrients (mainly sucrose) from leaves to other parts of the plant. It consists of sieve tubes, companion cells, phloem fibers, and phloem parenchyma. Unlike xylem, phloem can transport in both directions (bidirectional).
Key Points for NEET
- 1Transports organic food (sugars) - called translocation
- 2Living cells at maturity
- 3Sieve tubes lack nucleus, controlled by companion cells
- 4Bidirectional transport (source to sink)
- 5Movement explained by pressure flow hypothesis
Example
Sugars produced in leaves transported to growing fruits through phloem
Asked in NEET
Related Terms
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