A
hydathode is a type of
secretorySecretion is the process of elaborating, releasing, and oozing chemicals from a cell, a secreted chemical substance or amount of substance. In contrast to excretion, the substance may have a certain function, rather than being a waste product....
tissueTissue is a cellular organizational level intermediate between cells and a complete organism. Hence, a tissue is an ensemble of cells, not necessarily identical, but from the same origin, that together carry out a specific function...
in
leavesIn botany, a leaf is an above-ground plant organ specialized for photosynthesis. For this purpose, a leaf is typically flat and thin. There is continued debate about whether the flatness of leaves evolved to expose the chloroplasts to more light or to increase the absorption of carbon dioxide. In...
, usually of Angiosperms, that secretes water through
porePore may refer to:In animal biology and microbiology:* Sweat pore, an anatomical structure of the skin of humans used for secretion of sweat...
s in the
epidermisThe epidermis is a single-layered group of cells that covers plants leaves, flowers, roots and stems. It forms a boundary between the plant and the external world. The epidermis serves several functions, it protects against water loss, regulates gas exchange, secretes metabolic compounds, and ...
or margin of leaves, typically at the tip of a marginal tooth or serration. They probably evolved from modified stomata. It is involved in
guttationGuttation is the appearance of drops of xylem sap on the tips or edges of leaves of some vascular plants, such as grasses. Guttation is not to be confused with dew, which condenses from the atmosphere onto the plant surface.- Process :...
, where water is released from the top in order to transport the nutrients in the water from the
rootIn vascular plants, the root is the organ of a plant that typically lies below the surface of the soil. This is not always the case, however, since a root can also be aerial or aerating . Furthermore, a stem normally occurring below ground is not exceptional either...
s to the leaves. Hydathodes are connected to the plant vascular system by a vascular bundle.
Since the liquid being extruded is from the xylem it also contains salts, sugars, and organic compounds dissolved in water and this is sometimes seen to crystalize on evaporation, forming a white powdery substance on the leafs edge.
A
hydathode is a type of
secretorySecretion is the process of elaborating, releasing, and oozing chemicals from a cell, a secreted chemical substance or amount of substance. In contrast to excretion, the substance may have a certain function, rather than being a waste product....
tissueTissue is a cellular organizational level intermediate between cells and a complete organism. Hence, a tissue is an ensemble of cells, not necessarily identical, but from the same origin, that together carry out a specific function...
in
leavesIn botany, a leaf is an above-ground plant organ specialized for photosynthesis. For this purpose, a leaf is typically flat and thin. There is continued debate about whether the flatness of leaves evolved to expose the chloroplasts to more light or to increase the absorption of carbon dioxide. In...
, usually of Angiosperms, that secretes water through
porePore may refer to:In animal biology and microbiology:* Sweat pore, an anatomical structure of the skin of humans used for secretion of sweat...
s in the
epidermisThe epidermis is a single-layered group of cells that covers plants leaves, flowers, roots and stems. It forms a boundary between the plant and the external world. The epidermis serves several functions, it protects against water loss, regulates gas exchange, secretes metabolic compounds, and ...
or margin of leaves, typically at the tip of a marginal tooth or serration. They probably evolved from modified stomata. It is involved in
guttationGuttation is the appearance of drops of xylem sap on the tips or edges of leaves of some vascular plants, such as grasses. Guttation is not to be confused with dew, which condenses from the atmosphere onto the plant surface.- Process :...
, where water is released from the top in order to transport the nutrients in the water from the
rootIn vascular plants, the root is the organ of a plant that typically lies below the surface of the soil. This is not always the case, however, since a root can also be aerial or aerating . Furthermore, a stem normally occurring below ground is not exceptional either...
s to the leaves. Hydathodes are connected to the plant vascular system by a vascular bundle.
Since the liquid being extruded is from the xylem it also contains salts, sugars, and organic compounds dissolved in water and this is sometimes seen to crystalize on evaporation, forming a white powdery substance on the leafs edge. This crystallisation is very obvious in
halophyteA halophyte is a plant that naturally grows where it is affected by salinity in the root area or by salt spray, such as in saline semi-deserts, mangrove swamps, marshes and sloughs, and seashores. An example of a halophyte is the salt marsh grass Spartina alterniflora . Relatively few plant species...
s, plants adapted to live in high salt environments, and consequently the hydathodes are known as salt glands in those species.
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