MINISTRY OF DEFENCE

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  MINISTRY OF DEFENCE. Establishment Of National University In Islamabad Total position. 29 Domicile , All over Pakistan    Qualification  intermediate to bachelor positions . Project Engineer(Civil) account Officer  supervisor assistant office boy     How to apply.   Apply online through the link https://www.fgei-cg.gov.pk/nup-rec.php   Last date to apply  02 April 2023. No TA/DA Fo Interview 
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Hydrophytes,Halophytes,Mesophytes,xerophytes

Hydrophytes

These plants grow in water,founds in ponds,streams or lacks.these plants mostly under water but in some plants leaves are above water.

Characteristics.

I) Soft body without cuticle.
ii) Roots are absent (in some plants poorly present.
iii) whole body may perform function of absorption of water.
iv) upper leaves (above the water) contain stomata through which transpiration takes place.
v) those plants which are present underwater contain hydathodes(opening without guard cells) for removal of water.

Example: Hydrilla,lotus,Lilly plants

Halophytes:
                  These plants grow in marshy soil or salty soil.(near sea)(water extra,oxygen disappear,salts extra),these plants produced special roots in air to absorb oxygen,called respiratory rotes
Characteristics:
I) the amount of minerals in the soil is high and active transport occurs,roots absorb water from the soil.
iii) salt glands are present in the leaves which help to excrete salt and water from the body.

Mesophytes:
                 these plants grow in those soil which contain sufficient amount of water,these are the land plants with temperate regions.

Characteristics

I) Their roots are well developed.
ii) Body is covered by cuticle,which prevents transpiration
iii) have stomata for evaporation of extra amount of water. e.g. Mango,rose
iv) Some of rainy regions contain Hydathodes (Opening without guard cells),through which water is removed in the form of drops,process is called Guttation.

Xerophytes...

These plants grow in dry soil (contain less amount of water,deserts steep steep hills)
Ephimeral Plants.
Some plants do not face dry condition They pass this dry condition in the form of seeds,called ephimeral plants.
I)their roots are well developed,which absorb water from the deep.
ii) Desert plants like cactus produce roots on the surface of the soil to absorb rainy water very rapidly.
iii) Leaves and branches are modified into spines in some plants for preventing transpiration.
iv) Stem and leaves are covered by cuticle,some time leaves are decreased in size to prevent transpiration.


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