"Xylem and Pholem are the transporting channels of the plant." Explain
Answers
Answer:
Xylem transports and stores water and water-soluble nutrients in vascular plants. Phloem is responsible for transporting sugars, proteins, and other organic molecules in plants. Vascular plants are able to grow higher than other plants due to the rigidity of xylem cells, which support the plant.
Answer:
Xylem and phloem
Plants have tissues to transport water, nutrients and minerals.
Xylem transports water and mineral salts from the roots up to other parts of the plant, while phloem transports sucrose and amino acids between the leaves and other parts of the plant.
Cross-section of a plant root, showing a vascular bundle of xylem and phloem in the centre.
Xylem and phloem in the centre of the plant root
This table explains what is transported by the xylem and phloem:
XylemWater and mineralsTranspiration stream
PhloemSucrose and amino acidsTranslocation
Xylem
Mature xylem consists of elongated dead cells, arranged end to end to form continuous vessels (tubes).
Mature xylem vessels:
contain no cytoplasm
are impermeable to water
have tough walls containing a woody material called lignin
Phloem
Phloem consists of living cells arranged end to end. Unlike xylem, phloem vessels contain cytoplasm, and this goes through holes from one cell to the next.
Phloem transports sucrose and amino acids up and down the plant. This is called translocation. In general, this happens between where these substances are made (the sources) and where they are used or stored (the sinks).
This means, for example, that sucrose is transported:
from sources in the root to sinks in the leaves in spring time
from sources in the leaves to sinks in the root in the summer
Applied chemicals, such as pesticides, also move through the plant by translocation.