Cell organisation in plants

WHAT IS THE FUNCTION OF:FLOWERSTEMLEAFROOTS

WHAT ARE THE CELLS INSIDE THOSE PARTS OF PLANT?

Cell organisation in plants

TISSUES 1. Meristematic tissues

2. Permanent tissues

Small cells – thin walls, large nuclei, dense cytoplasm and no vacuole

Young, cell divide actively but not undergo differentiation

at the tips of roots

Epidermal tissues

Ground tissues

Vascular tissues

Permanent tissues

1.Epidermal tissue• Outermost layer – covers the stems, leaves

and roots of young plants.• Flat and has large vacuole• Wall - covered with cuticle• Root – has root hairs• Chloroplast – guard cells

Epidermal tissue

Permanent tissue

2. Ground tissue• parenchyma – thin primary walls and large vacuole ; store sugar and starch ; gives support and shape to herbaceous plants.(leaf)• collenchyma – unevenly thickened cell walls; supports non-woody plants, young stems and petioles.(stem)• sclerenchyma – cell walls uniformly thickened by lignin and may be dead; give support and mechanical strength.(root)

Parenchyma tissue

Collenchyma tissue

Thickened cell wall

Sclerenchyma tissue

Vascular tissue

Organs and systems in plants

Regulating the internal environmentDefinitionWhy need to maintain an optimal

internal environment?Factors that affect the internal

environment?Homeostasis??

- system that regulates its internal environment so as to maintain a stable, constant condition

Homeostasis