Plant Tissues, Organs and Systems

• How is epidermal tissue adapted to its function?

  Epidermal tissue covers the entire plant. It has a waxy cuticle which reduces water loss from the leafs surface.
• Label the structure of a leaf

  Label.

  A) Cuticle

  B) Epidermis

  C) Palisade Mesophyll

  D) Vein

  E) Lower Epidermis

  F) Spongy Mesophyll

  G) Stomata

  
• How is spongy mesophyll adapted to its function?

  Spongey mesophyll has lots of air spaces which allows gases to diffuse in and out
• How is xylem adapted to its function?

  Made up of dead cells which form a continuous hollow tube - allows the movement of water and mineral ions

  Strengthened by Lingin - makes the vessel strong and waterproof

  Has bordered pits which allows minerals to be transported to specific places.
• How is the phloem adapted to its function?

  Made up of elongated living cells

  Cells have sieve plates that connect them - cell sap can move through plates into other cells

  Sieve tubes have few organelles to allow efficient transport of substances.
• How is the meristem adapted to its function?

  Made up of stem cells which can differentiate into many different types of cells allowing plant growth.
• What is the function of the guard cells?

  Regulate stomata opening and closing.
• How are stomata adapted to their function?

  More stomata on the base of the leaf - minimises water loss as this side is more shaded and cooler

  Has Guard cells which open and close the plant
• How are root hair cells adapted to their function?

  Large surface area - maximises the rate of absorption

  Contains lot of mitochondria - allows energy for active transport of mineral ions
• What is translocation?

  The movement of dissolved sugars from the leaves to other parts of a plant.
• What is transpiration?

  Transpiration is the process by which plants release water vapour into the atmosphere through their leaves.
• How does transpiration work?

  Water evaporates from the leaf via stomata

  Water molecules cohere together and more water is pulled up by the xylem in an unbroken column

  More water is taken in from the soil - creating a continuous evaporation stream
• How does temperature affect the rate of transpiration?

  As temperature increases, the rate of transpiration generally increases due to the increased evaporation of water from plant leaves and increased diffusion.