Specialized Plant Cells and Modifications

Specialized Cells in Plants

• Guard Cells: Control transpiration by regulating stomatal openings; possess cell walls of varying thickness for flexibility.
• Root Hair Cells: Maximize absorption of water and minerals from soil with elongated, thin structure and large surface area.
• Photosynthetic Cells: Conduct photosynthesis to produce food; characterized by a high number of chloroplasts for efficient light capture.
• Xylem Vessels: Facilitate water and mineral transport from roots upwards; contain lignin for structural support and lack protoplasm, creating a continuous flow.

Cell Modifications

• Adaptations acquired post cell division enhance functionality and efficiency.

Types of Cell Modifications

• Apical Modifications: Enhance absorption, secretion, or movement; examples include microvilli (increase surface area) and cilia (aid in movement).
• Basal Modifications: Improve attachment and transport within tissues; features include hemidesmosomes and basal infoldings for stability.
• Lateral Modifications: Promote cell adhesion and intercellular communication; include tight junctions, desmosomes, and gap junctions for structural integrity and signaling.

Cilia

• Hair-like organelles extending from cell surfaces, involved in movement or sensation.
• Two types:
  • Non-motile Cilia: Serve primarily as sensory receptors.
  • Motile Cilia: Assist in locomotion by creating movement.

Flagella

• Long, whip-like structures composed of protein filaments; crucial for motility in various cells.

Villi or Microvilli

• Tiny, finger-like projections that increase surface area for absorption, playing a key role in nutrient uptake.

Pseudopods

• Temporary cytoplasmic extensions known as "false feet"; facilitate movement and the ingestion process in certain cells.