Specialisation in Animal Cells

Cell Differentiation and Specialization

• Cells differentiate to form specialized cells during organism development.
• Animal cells typically differentiate early, while plant cells can differentiate throughout life.
• Differentiation leads to specialized sub-cellular structures for specific functions.

Observing Specialized Cells

• Key questions:
  • How does the cell's structure differ from a generalized cell?
  • How does this structural difference aid its function?

Nerve Cells

• Function: Carry electrical impulses rapidly.
• Adaptations:
  • Dendrites: Connect to other nerve cells.
  • Axon: Carries the nerve impulse (can be very long).
  • Synapses: Use transmitter chemicals to pass impulses; contain many mitochondria.

Muscle Cells

• Function: Contract and relax.
• Striated muscle cells: Work in tissues to move bones.
• Smooth muscle cells: In digestive system, contract to move food.
• Adaptations (Striated):
  • Special proteins: Slide for contraction.
  • Many mitochondria: Transfer energy for reactions.
  • Glycogen storage: Broken down for cellular respiration.

Sperm Cells

• Function: Fertilize eggs by delivering male genetic information.
• Adaptations:
  • Long tail: Moves sperm.
  • Middle section: Full of mitochondria for energy.
  • Acrosome: Stores digestive enzymes to break down egg layers.
  • Large nucleus: Contains genetic information.

Key Points

• Cell differentiation leads to specialized cells.
• Specialized animal cells gain unique sub-cellular structures.
• Examples: Nerve, muscle, and sperm cells.
• Cells function within tissues, organs, or whole organisms.