Specialised cells

• Red Blood Cells


  → They have no nucleus - carry more oxygen

  → Bi-concave shape - dimpled surface which increases the surface area for oxygen uptake
• Sperm Cells


  → Large nucleus - contains half the genetic information

  → Contain digestive enzymes at the tip of the head

  →Many mitochondria to generate energy for swimming

  → Long tail (flagellum) and streamlined shape
• Muscle Cell

  → Elongated spindle shaped cells

  → Contain many mitochondria

  → Can contract - can pull our bones around. This requires a lot of energy.
• Nerve Cell

  → Long and thin

  → Form connection with other neurones via the Branched endings

  → carry electrical impulses in one direction, very quickly

  → Insulated with a fatty material called Myelin

  → Release neurotransmitter chemicals across synapses
• Palisade Cell

  → Found in the upper layer of a leaf

  → Large surface area

  → Contains lots of chloroplasts for photosynthesis
• Phloem Cell


  → Found with cells in the veins

  → They are made up of living cells

  → At the end of each cell there a perforated sieve plate which allows dissolved substances to flow through the cytoplasm of each cell

  → Phloem carry sugars around the plants
• Xylem Cell


  → found within the stems of plants

  → originally living cells stacked end to end

  → the cells die and the contents disappear to form a continuous hollow tube to transport water up the stem
• Root Hair Cells


  → Found in the Roots of plants

  → No chloroplasts - no light for photosynthesis underground

  → Elongated ‘hair’ - projects into soil and increases the surface area for absorbing water and minerals

  → Two sausage-shaped cell on either side of the stomata on the underside of a leaf

  → They are able to change shape to open and close the stomata