Biology Project

COLLENCHYMA

Annabelle Edwards

Photograph

Diagram

Unique Structural Features• The cell wall structure is a unique feature, The

thickenings are deposited unevenly; thickenings are present at the corners of the cells, and contain cellulose and pectin, collenchyma cells show thin and thick wall portions depending on the direction of the cut.

• Inter cellular spaces are absent• A few chloroplasts may be present in the cells• Collenchyma cells are considerably elongated• Their cell walls don't contain lignin

Where is it found?

Collenchyma tissues are mainly found under the epidermis in young stems in the large veins of leaves. The cells are composed of living, elongated cells running parallel to the length of organs that it is found in.

What do they do?

Collenchyma is primarily a mechanical tissue adapted for support of grow ing organs. The thick walls and close packing, make it a strong tissue and because their cell walls don't contain lignin, they are stretchy and can change size so as a young leaf grows, collenchyma cells can elongate and still give the leaf structure

Features linked to Function

• The cells are composed of living, elongated cells running parallel to the length of organs that it is found in. the cells have thick cellulose cell walls which thickened at the corners. This makes the plants more structure of the plant flexible whilst still holding desired structure.

• Intercellular air spaces are absent or very small to make them more closely packed increasing strength

• The cells contain living protoplasm and they sometimes contain chloroplasts so that photosynthesis can take place.