Plant Tissues

• By the end of this video you should be able to describe the roles of the different tissues in a plant
• Photosynthesis takes place in leaves
• The leaf is a plant organ that contains different tissues
• Epidermal cells


  Very thin cells that form the upper and lower epidermis of the leaf
• Upper epidermis


  • Transparent to allow light to pass through
  • Covered with a waxy cuticle to reduce water evaporation
• Lower epidermis


  • Contains tiny pores called stomata that allow carbon dioxide in and oxygen out
  • Has guard cells on either side of the stomata
• Palisade mesophyll


  Packed full of chloroplasts that contain chlorophyll to absorb light energy for photosynthesis
• Spongy mesophyll


  • Full of air spaces that allow carbon dioxide to diffuse to the palisade cells and oxygen to diffuse out
• Xylem


  Transports water and dissolved mineral ions from the roots to the stem and leaves
• Phloem


  Transports dissolved sugars produced by photosynthesis from the leaves to the rest of the plant
• Translocation


  The movement of sugars through phloem tissue
• Meristem tissue


  Contains stem cells that can differentiate into different types of plant tissue
• Meristem tissue is found at growing tips such as shoots and roots
• You will find plenty of questions on plant tissues in the revision workbook