Plant Cell Organisation

• The leaf is an example of an:

  organ
• The root, stem, and leaves, together make up an: 

  organ system
• A guard cell is an example of a: 

  cell
• The palisade mesophyll layer is an example of a: 

  tissue
• Which structure is highlighted on the diagram above?

  Palisade mesophyll layer

  
• Which structure is highlighted on the diagram 

  Spongy mesophyll layer

  
• Which structure is highlighted on the diagram

  Lower epidermis

  
• What name is given to the cells highlighted on the diagram above?

  guard cells

  
• What name is given to the openings indicated on the diagram

  Stomata

  
• The upper epidermis is transparent so that light can pass through it. This means that as much light as possible can reach the palisade mesophyll cells below, and be used in photosynthesis.
• Which structures help to minimise water loss?

  waxy cuticle

  Guard cells which can close stomata
• 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. At night time there is no light for photosynthesis, so plants don't need to absorb carbon dioxide. This means they can close their stomata and conserve water.
• What is meristem tissue and where is it found?

  Stem cells

  Tips of shoots and roots