Specialised Cells

  1. Understanding Specialised Cells

• Specialised cells are those which have adapted to carry out a specific function efficiently. • These adaptations occur as cells differentiate, allowing them to perform specific roles in the body. • Examples include sperm cells, red blood cells, nerve cells, root hair cells, and muscle cells.

  1. Sperm Cells

• Sperm cells are developed for reproduction. • They have a streamlined shape for ease of movement and a tail that propels the cell forward. • The genetic information is held in the head of the sperm, which also contains enzymes to help penetrate the egg for fertilisation.

  1. Red Blood Cells

• Red blood cells carry oxygen from the lungs to all the cells in the body. • Their biconcave disc shape increases the surface area for oxygen absorption and also helps cells to squeeze through narrow blood vessels. • Red blood cells do not have a nucleus, allowing more room to carry oxygen.

  1. Nerve Cells

• Nerve cells, or neurons, transmit electrical signals around the body. • They have long extensions called axons to carry impulses over long distances, and branched terminations to connect with numerous other neurons. • The cell body contains a nucleus and extends dendrites, which receive signals from other neurons.

  1. Root Hair Cells

• Root hair cells in plants are specialised to absorb water and minerals from the soil. • Each cell has a long ‘hair’ that extends from its surface, dramatically increasing its surface area to improve absorption. • They do not carry out photosynthesis, so they contain no chloroplasts.

  1. Muscle Cells

• Muscle cells are specialised to contract and relax to allow for movement. • They contain protein filaments, actin and myosin, which slide past each other to cause contraction. • Many mitochondria supply the energy needed for these contractions.

  1. Key Points

• Much of an organism’s internal communication, protection and structural integrity depend on the specialisation of its cells. • Specialised cells carry out their functions more efficiently due to their specific adaptations. • Understanding the basic structure and function of these cells can help in understanding more complex biological processes.