specialisation & differentiation

• Not all cells become specialised
• Cells divide to replace and repair cells
• Energy is transferred by respiration, which mostly takes place in the mitochondria. So any cell that needs lots of energy to do its job will have lots of mitochondria
• Specialised cell


  A body cell that performs a specific function. Most cells in an organism are specialised
• Cell differentiation


  1. The process by which a cell changes to become specialised for its job

  2. As cells change, they develop different subcellular structures and turn into different types of cell
• Specialised cells


  • Nerve cells
  • Muscle cells
  • Root hair cells
  • Phloem and xylem cells
• Nerve cells


  • Long to cover more distance
  • Branched connections at the ends to connect to other nerve cells and form a network throughout the body
• Muscle cells


  • Long so they have space to contract
  • Contain lots of mitochondria to transfer the energy needed for contraction
• Root hair cells


  • Grow into long hairs that stick out into the soil
  • Give the plant a big surface area for absorbing water and mineral ions from the soil
  • Don't contain any chloroplasts as they are underground and don't carry out photosynthesis
• Phloem and xylem cells

  • Form phloem and xylem tubes to transport substances such as food and water around plants
  • Cells are long and joined end to end
  • Xylem cells are hollow in the centre
  • Phloem cells have very few subcellular structures so substances can flow through them
• the advantages of specialisation are that it allows for greater efficiency, increased speed of reaction, better use of resources and improved survival rates.
• differentiation is when cells become more specialised as they develop into tissues, organs or systems
• The disadvantages of specialisation include reduced flexibility, decreased ability to adapt to new conditions and an increase in vulnerability to disease or damage.
• a tissue is a group of similar cells working together to perform a specific task
• organs are groups of tissues which work together to perform a particular function
• During development, stem cells divide by mitosis to produce daughter cells which then undergo differentiation to form specific cell types with their own unique functions.
• Stem cells are undifferentiated cells found in embryos and some adult tissues that have the potential to develop into many different specialized cell types.
• Embryonic stem cells (ESC) are derived from early stage embryos and have the capacity to give rise to all cell types in the body.
• A system is a collection of organs which work together to carry out a major life process
• an organ is made up of two or more types of tissue which work together to perform a particular function
• Differentiated cells are highly adapted to their role within the organism but cannot change roles if required
• An example of this would be the circulatory system which consists of the heart, blood vessels and blood