Lecture Notes on Specialized Cells

Introduction

• Cells are not uniform; there are many types within both plants and animals.
• Specialized cells are differentiated to perform specific functions.

Plant Cells

Palisade Cell

• Function: Light absorption and photosynthesis.
• Adaptations:
  • Large surface area.
  • Many chloroplasts for photosynthesis.

Animal Cells

Red Blood Cell

• Function: Oxygen transport.
• Adaptations:
  • Biconcave shape for a large surface area.
  • No nucleus in humans, allowing more room for hemoglobin.

Nerve Cell

• Function: Transmitting nerve impulses.
• Adaptations:
  • Long structure for transmitting information over distances.
  • Connections at each end to connect with receptors or other nerve cells.

Sperm Cell

• Function: Fuse with an egg cell (ovum) to produce a zygote.
• Adaptations:
  • Tail for swimming.
  • Many mitochondria for energy.
  • Enzymes in the head within the acrosome.

Ovum (Egg Cell)

• Function: Fuses with sperm to create a zygote.
• Adaptations:
  • Large size and cytoplasm with yolk for energy.
  • Outer layer prevents entry of multiple sperm.

Ciliated Cells

• Function: Moving mucus (trapping dust and pathogens) out of the lungs.
• Adaptations:
  • Hair-like projections (cilia) for movement of mucus.
  • Includes goblet cells that produce mucus.

Root Hair Cells

• Function: Intake of water and minerals from soil.
• Adaptations:
  • Large surface area for efficient absorption.

Xylem Vessel

• Function: Transporting water.
• Structure:
  • Composed of hollowed-out remains of cells.
  • Strengthened with a cellulose wall and lignin.
  • Hollow lumen for water passage.