Plant Tissues Overview

Types of Plant Tissues

• Meristematic Tissues

  • Composed of undifferentiated cells.
  • Capable of continuous division and growth.
  • Found in regions of growth (roots, shoots).

• Permanent Tissues

  • Differentiated cells that have specific functions.
  • Do not divide (most cases) after maturation.
  • Subdivided into simple and complex tissues.

Functions Of Plant Tissues

• Meristematic Tissues

  • Provide growth in length (apical meristems) and girth (lateral meristems).
  • Aid in forming new organs (roots, leaves).

• Permanent Tissues

  • Support and structure (sclerenchyma, collenchyma).
  • Conduct nutrients and water (xylem, phloem).
  • Store food (parenchyma).
  • Protect against pathogens and physical injury (epidermis).

Plant Tissue Organization

• Simple Tissues
  • Composed of a single cell type.
  • Types: Parenchyma, Collenchyma, Sclerenchyma.
• Complex Tissues
  • Composed of multiple cell types.
  • Types: Xylem (water transport), Phloem (nutrient transport).

Meristematic Tissues

• Apical Meristem

  • Located at tips of roots and shoots.
  • Responsible for primary growth (length).

• Lateral Meristem

  • Includes vascular cambium and cork cambium.
  • Responsible for secondary growth (girth).

• Intercalary Meristem

  • Located at internodes or leaf bases.
  • Contributes to regrowth of plants after cutting.

Permanent Tissues

• Simple Permanent Tissues

  • Parenchyma:
    • Thin-walled, involved in storage and metabolism.
  • Collenchyma:
    • Thick-walled, provides flexible support.
  • Sclerenchyma:
    • Thick-walled, provides rigid support, dead at maturity.

• Complex Permanent Tissues

  • Xylem:
    • Transports water and minerals; consists of tracheids, vessel elements, and fibers.
  • Phloem:
    • Transports sugars; consists of sieve elements and companion cells.

Types of Plant Tissues

• Meristematic tissues consist of undifferentiated cells that can continuously divide and promote growth.
• Found in areas of active growth such as the tips of roots and shoots.
• Permanent tissues are comprised of differentiated cells that perform specialized functions and typically do not divide after maturation.
• Permanent tissues are categorized into simple (one cell type) and complex (multiple cell types) tissues.

Functions Of Plant Tissues

• Meristematic tissues facilitate growth in length through apical meristems and in girth through lateral meristems.
• Permanent tissues contribute to plant support and structure with sclerenchyma and collenchyma.
• They are essential for nutrient and water conduction via xylem and phloem.
• Storage of food occurs in parenchyma, while the epidermis protects plants from pathogens and physical damage.

Plant Tissue Organization

• Simple tissues include parenchyma (storage and metabolism), collenchyma (flexible support), and sclerenchyma (rigid support).
• Complex tissues consist of xylem for water transport and phloem for the transport of nutrients, such as sugars.

Meristematic Tissues

• Apical meristem is located at the tips of roots and shoots, driving primary growth (length).
• Lateral meristem includes vascular cambium and cork cambium, facilitating secondary growth (girth).
• Intercalary meristem is located at internodes or leaf bases, playing a role in regrowth after plant cutting.

Permanent Tissues

• Simple permanent tissues consist of parenchyma (thin-walled and involved in storage), collenchyma (thick-walled for flexible support), and sclerenchyma (thick-walled, providing rigid support, and dead at maturity).
• Complex permanent tissues are comprised of xylem, which transports water and minerals through tracheids, vessel elements, and fibers, and phloem, responsible for sugar transport through sieve elements and companion cells.