B1.5

• Photosynthetic cell adaptations


  Contain chloroplasts that contain chlorophyll that absorbs energy from the sun for photosynthesis.

  Usually arranged in layers on leaves and surface of stems to absorb as much sunlight.

  Large permanent vacuole that maintains cells rigidity via the movement of water in osmosis.This helps keep leaves stretched and stem strong.
• Root Hair cell adaptations

  High surface area increasing water intake

  Many mitochondria to provide energy for active transport.

  Large permanent vacuole that speeds up osmosis of water from soil to the roots.
• Xylem cell adaptations

  Lignin builds up in them and so form long hollow tubes, allowing water and dissolved minerals to move freely.

  Spirals and rings of lignin make them strong enabling them to withstand the pressure of the water.The stem is also supported.
• Phloem cell adaptations


  Cell walls break down to form sieve plates, that allow dissolved food form photosynthesis to move to where it is needed.

  They loose a lot of their internal structures and so rely on companion cells to keep them alive.The energy produced by the mitochondria of the companion cells is transferred to the xylem to aid the movement of food.
• • Many types of plant cells retain the ability to differentiate throughout life.