Organs in Plants

Página 1

Plants are multicellular organisms, just like animals.

They also usually contain differentiated cells, tissues and organs.

Tissues

The table shows some examples of plant tissues and their functions.

Epidermal tissue --- Covers the plant

Mesophyll --- Carries out photosynthesis

Xylem and phloem --- Transport of substances around the plant

Organs Examples of plant organs include:

Roots

Stems

Leaves

Leaves Leaves are adapted to absorbing sunlight for photosynthesis.

Adaptations of a leaf:

Chlorophyll ---- To absorb sunlight

Large surface area ---- To absorb more light

Stomata ---- To let carbon dioxide diffuse into the leaf

Thin ---- Short distance for carbon dioxide to diffuse into leaf cells

Network of veins ---- To support the leaf and transport water and carbohydrates

The leaf You should be able to describe the internal structure of a leaf.

Adaptations:

Thin, waxy cuticlemade of wax - To protect the leaf without blocking out light

Thin, transparentepidermis - To allow more light to reach the palisade cells

Layer of palisade cells on the top surface - To absorb light

Many chloroplasts in the palisade cells - To increase absorption of light

Spongy mesophyllinside the leaf - Air spaces allow carbon dioxide to diffuse through the leaf, and increase the surface area

Organs in a plant

The Leaf