Cell Specialisation and Stem Cells

• What is differentiation in cell biology?

  The process by which a cell changes
• When do most animal cells lose the ability to differentiate?

  At an early stage
• Which type of cells never lose the ability to differentiate?

  Many plant cells
• What are the five types of specialised cells?

  1. Sperm cell — reproduction
  2. Nerve cell — rapid signalling
  3. Xylem and phloem — transporting substances
  4. Muscle cell — contraction
  5. Root hair cell — absorbing water and minerals
• What is the function of a sperm cell?

  Reproduction
• How is a sperm cell adapted for its function?

  Long tail and streamlined head
• What is the function of a nerve cell?

  Rapid signalling
• How is a nerve cell adapted for its function?

  Long and branched for connections
• What do xylem and phloem cells do?

  Transport substances
• What is the function of muscle cells?

  Contraction
• How are muscle cells adapted for their function?

  Long with many mitochondria
• What is the function of root hair cells?

  Absorbing water and minerals
• How are root hair cells adapted for their function?

  Large surface area for absorption
• Why are xylem cells hollow?

  To allow substances to flow through
• Why do phloem cells have few subcellular structures?

  To allow substances to flow through
• What are stem cells?

  Undifferentiated cells that can divide
• What can stem cells differentiate into?

  Many other types of cell
• Where can stem cells be obtained from?

  Adult bone marrow, human embryo, plant meristem
• What is a potential use of stem cells in medicine?

  Treating paralysis with nerve cells
• What is therapeutic cloning?

  Creating an embryo with the same genes as the patient
• What is a risk associated with using lab-grown stem cells?

  They could get a virus
• How can stem cells be used in plants?

  To produce clones of whole plants
• Why are stem cells useful for cloning crops?

  They grow plants quickly and cheaply
• What is an example of using stem cells in agriculture?

  Cloning crops with desired features
• What are the advantages and disadvantages of using stem cells in medicine?

  Advantages:

  • Can treat various diseases
  • Can regenerate damaged tissues

  
  

  Disadvantages:

  • Risk of infection
  • Ethical concerns