Cell structure

• Cell Membrane


  Separates the cell from its environment; controls entry and exit of substances.
• Cytoplasm


  Jelly-like substance where chemical reactions occur
• Common Structures in Both animal and plant cell

  Nucleus, cytoplasm, cell membrane, mitochondria, ribosomes.
• Organelles in Eukaryotic Cells


  • Nucleus: Contains genetic material.
  • Mitochondria: Site of aerobic respiration.
  • Ribosomes: Site of protein synthesis
• Additional Organelles in Plant Cells


  • Cell Wall: Provides structure and support.
  • Chloroplasts: Site of photosynthesis.
  • Permanent Vacuole: Maintains cell turgidity by storing cell sap.
• Unique to Plant Cells

  • Cell Wall: Made of cellulose.
  • Chloroplasts: For photosynthesis.
  • Large Permanent Vacuole: Stores cell sap and maintains turgor.
• Small Vacuoles in Animal Cells


  Animal cells may have temporary, small vacuoles.
• Cell Differentiation


  Process by which a cell changes to become specialized.
• Specialized Cells Examples

  a

  • Ciliated Cell: Moves mucus in the trachea.
  • Nerve Cell: Conducts impulses; long shape aids communication.
  • Red Blood Cell: Transports oxygen; biconcave shape increases surface area.
  • Root Hair Cell: Absorbs water and minerals; long extension increases surface area.
  • Palisade Cell: Found in leaves; performs photosynthesis with numerous chloroplasts.
• Types of Stem Cells


  • Embryonic Stem Cells: Totipotent, can form any cell type.
  • Adult Stem Cells: Found in bone marrow, mainly forms blood cells.
  • Plant Stem Cells (Meristem): Differentiate into various plant cell types
• Application of stem cells

  Potential to treat diseases like diabetes and paralysis by generating specialized cells for damaged organs.
• Ethical Considerations


  Debate exists over the use of embryonic stem cells due to ethical and social concerns.