Plant tissues, organs and organ systems

• Name six plant tissues.

  Epidermal, palisade mesophyll, spongy mesophyll, xylem, phloem, meristem
• What is the function of epidermal tissue?

  To cover and protect the leaf
• What is the function of palisade mesophyll tissue?

  The site of photosynthesis
• What is the function of spongy mesophyll tissue?

  The site of gas exchange and photosynthesis
• What is the function of xylem tissue?

  Transport of water and dissolved ions
• What is the function of phloem tissue?

  Transport of sugars made in photosynthesis
• What is the function of meristem tissue?


  To divide into cells at the growing tips of shoots and roots
• Name three plant organs

  Leaf, stem, roots
• What is transpiration?


  The movement of water from the roots to the leaves, eventually leaving the leaves via evaporation
• Name four factors which affect the rate of transpiration in plants.

  1. Temperature
  2. Humidity
  3. Air movement
  4. Light intensity
• What is translocation?


  The movement of sugars from the leaves to the rest of the plant
• Describe the adaptations of xylem tissue

  Hollow tubes strengthened by lignin in the walls
• Describe the adaptations of phloem tissue

  Elongated cells with pores in the end cell walls to aid the movement of dissolved sugars
• What is the role of stomata and guard cells?

  To control gas exchange and water loss