7. Hou are water and consists transported in
plants ?
Answers
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.
Answer:
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.
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.