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Water evaporates from the mesophyll cells into air spaces in the leaf. If the air surrounding the leaf has less water vapour than the air in the intercellular spaces, water vapour will leave the leaf through stomata.
Xylem vessels are a tube like structure which transport water from the roots to the shoots. They are dead cells which contain no cytoplasm> However their wall is thickened by the substance lignin which supports the cell and prevents collapsing when tension builds up.
xylem vessels have a tube like structure, they carry water from roots to shoots. They are made of dead cells joined together, and on the side they contain lignin which strengthens it. This also provides support to the plant making it straight and not bendy.
Xylem vessels are tube-like structures. Their walls are thickened with a substance called lignin, which helps to support the xylem vessels and stops them collapsing.
Xylem carry water up. They are continous pipes which continue the whole way up. They contain no cytoplasm. Their walls are thickened by with ansubstance called lignin which give support to the cell when the tension builds up.
Xylem vessels are very long, tube-like structures. They contain no cytoplasm. Their walls are thickened with a substance called lignin, which helps to support the xylem vessels and stops them collapsing inwards.
As the cell gets older, the amount of lignin increases. Water and ions move into and put of the vessels through small pores in the walls where lignin isn’t present.
Water evaporates from the mesophyll cells into air spaces in the leaf. If the air surrounding the leaf has less water vapour than the air in the intercellular spaces, water vapour will leave the leaf through stomata.
Xylem vessels are a tube like structure which transport water from the roots to the shoots. They are dead cells which contain no cytoplasm> However their wall is thickened by the substance lignin which supports the cell and prevents collapsing when tension builds up.
xylem vessels have a tube like structure, they carry water from roots to shoots. They are made of dead cells joined together, and on the side they contain lignin which strengthens it. This also provides support to the plant making it straight and not bendy.
Xylem vessels are tube-like structures. Their walls are thickened with a substance called lignin, which helps to support the xylem vessels and stops them collapsing.
Xylem carry water up. They are continous pipes which continue the whole way up. They contain no cytoplasm. Their walls are thickened by with ansubstance called lignin which give support to the cell when the tension builds up.
Xylem vessels are very long, tube-like structures. They contain no cytoplasm. Their walls are thickened with a substance called lignin, which helps to support the xylem vessels and stops them collapsing inwards.
As the cell gets older, the amount of lignin increases. Water and ions move into and put of the vessels through small pores in the walls where lignin isn’t present.