leaf structure

• leaf structure

  
• waxy cuticle


  acts as a protective layer ontop of leaf+prevents water from evaporating
• upper epidermis


  thin+transparent to allow sunlight to pass through and reach the palisade layer below
• palisade mesophyll 


  column-shaped cells where chloroplasts are found
• what does the palisade cells being column shaped help with

  it allows them to absorb more light+maximizes photosynthesis
• spongy mesophyll


  has air spaces which increases the SA:vol and allows the diffusion of gases (mostly co2)
• lower epidermis


  contains guard cells+stomata
• guard cells


  absorb/ lose water to open/close the stomata in order to allow co2 to diffuse in and oxygen to diffuse out
• stomata 


  where gas exchange occurs

  • co2 diffuses in from air+oxygen diffuses out
  • water can also evaporate here
  • found at a larger concentration at the underside of leaf to reduce water loss
  • opens during day+closes during night
• vascular bundle 


  consists of the xylem +phloem to transport substances to leaf+take away glucose produced by photosynthesis

  • also helps support leaf's structure
• xylem


  transports water from roots to shoots for:

  • mesophyll cells to use in photosynthesis
  • transpiration from stomata
• phloem


  transports sucrose+amino acids around the plant