EDEXCEL UNIT

2 PLANT STRUCTURE  AND FUNCTION 

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PARENCHYMA

1. Live cells

2. They function in storage, photosynthesis, and as the bulk of ground and vascular tissues.

3. Palisade parenchyma cells are elongated cells located in many leaves just below the epidermal tissue.

4. Spongy mesophyll cells occur below the one or two layers of palisade cells.

5. Parenchyma cells also occur within the xylem and phloem of vascular bundles.

COLLENCHYMA

1. Live cells

2. These cells are isodiametric and elongated

3. Cell walls are unevenly thickened.

4. Has only primary cell wall

5. It provides mechanical support to the growing parts of the plant.

SCLERNCHYMA

1. Sclerenchyma cells support the plant.

2. They often occur as bundle cap fibers.

3. Sclerenchyma cells are characterized by thickenings in their secondary walls. .

4. A common type of schlerenchyma cell is the fiber.

5. Sclerenchyma is composed of dead cells with extremely thick secondary walls

6. Cell walls composed of cellulose and lignin