plant organistation

• Name a plant organ

  leaf
• name a plant cell

  guard cell
• Why is the upper epidermis transparent?

  So that light can pass through it to the palisade layer
• Which structures help to minimise water loss.

  waxy cuticle

  Guard cells which can close stomata
• what happens when the plant has lots of water?

  If there is plenty of water in the leaf, guard cells become turgid, which opens the stomata. This allows carbon dioxide to enter the leaf, but also allows water to escape.
• At night time, when photosynthesis can't take place, are the stomata normally open or closed?


  closed
• what is meristem tissue and where is it found?

  Meristem tissue is made up of plant stems cells. It's found in the growing parts of the plant such as the tips of shoots and roots.
• function of the xylem

  Transports water and minerals up the plant
• function of phloem

  transport sugar
• function of the stomata

  holes in the leaf for gas exchange
• Function of spongy mesophyll

  has air spaces for faster diffusion
• Function of waxy cuticle

  prevent water loss, thin and transparent to allow light into the palisade cells.
• Function of Palisade layer

  Packed with chloroplasts, main site of photosynthesis
• function of the upper epidermis

  allows light to the palisade mesophyll below and produces the waxy layer