cell specialisation 1.1.3

• cells can be specialised to carry out a particular function
• sperm cells are specialised for reproduction
• the function of a sperm is to get the male DNA to the female DNA
• the sperm has a long tail and streamlined head to help it swim to the egg
• there are lots of mitochondria in the sperm cell to provide the energy needed
• the sperm also carries enzymes in its head to digest through the egg cell membrane
• nerve cells are specialised for rapid signalling
• the function of nerve cells is to carry electrical signals from one part of the body to another
• the nerve cells are long (so they have space to contract) and contain lots of mitochondria to generate the energy needed for contraction
• root hair cells are used for absorbing water and minerals
• root hair cells are the cells on the surface of plant roots, which grow into long 'hairs' that stick out into the soil
• the surface are of the plant is therefore big due to all the root hair cells, to increase absorption of water and mineral ions from the soil
• xylem and phloem cells are for transporting substances
• xylem and phloem cells form phloem and xylem tubes to transport substances such as food and water around plants
• to form the xylem and phloem tubes, the cells are long and joined end to end
• xylem are hollow and phloem cells have very few subcellular structures, so stuff can flow through