Plant structures

What is the order of organisation in a plant cell

Cells→tissues→organs→organ systems→organisms

What are the main plant organs involved in transport

Roots, leaves, stems

Give an example of a plant organ

Leaf

What do leaves need for photosynthesis

Light energy, carbon dioxide and water

Where does water come from in plants

soil

What tissue transports water

Xylem

Direction of xylem transport

Roots→stem→leaves

How does carbon dioxide enter the leaf

Diffusion through the stomata

Where are most stomata found

Lower epidermis

Why are there many stomata

To allow gas exchange for photosynthesis

What is the function of the spongy mesophyll

Contains air spaces to help gasses diffuses

What is the function of the palisade mesophyll

Main site of photosynthesis, packed with chloroplasts

Why is the upper epidermis transparent

To allow light to reach palisade cells

What does the phloem transport

Sugars (product of photosynthesis)

Direction of Phloem transport?

Leaves→ rest of the plant

What is the main problem leaves face

Water loss due to evaporation

What is the waxy cuticle

Waterproof lipid layer that reduces water loss

What is a stoma

Gap between two guard cells

Why are stomata important

allows gas exchange

What happens when guard cells are turgid

Stomata opens→more Carbon dioxide enters

What happens when guard cells are flaccid

Stomata closes→less water loss

Why do guard cells become flaccid

Loss of water via osmosis

What happens to stomata at night

They close

Why are most stomata located on the underside of the leaf

Cooler and shader→less evaporation

Where is meristem tissue found

Tips of roots and shoots

What is the function of meristem tissue

Divide and differentiate to allow the plant to grow

Picture of the leaf diagram