xerophyte& hydrophye comment

[ahmedmoseilhy]

 

Xerophytic & Hydrophytic

·

Xerophytic leaf ( T.S in Calamagrostis leaf )

1. The leaf cruled.
2. Lower epidermis has thick cuticle without stomata .
3. Upper epedermis folded into ridges & furrows lined with hairs and sunken stomata .
4. Mesophyll modifiedinto lignified parenchyma .
5. The vascular stem well developed .

·

Xerophytic stem ( T.S in Retama stem )

1. Epidermis folded into ridges & furrows lined with hairs & sunken stomata , Presence of thick cuticle .
2. Presence of stone cellls & sclerenchyma .
3. Cortex narrow & vasicular tissue are situated on aperiphery of wide pith .

·

Hydrophytic stem ( T.S in Elodea stem )

1. Epidermis with thin cuticle & thin walls .
2. Stomata found on the upper surface of floating plant , Immersed plants are usually devoid of stomata .
3. Presence of air chambers .
4. Reduction of supporting & protective tissue .
5. The vascular tissue are much reduced especially the xylem .

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ahmedmoseilhy