1103 6 Tissue Structure & Function

Tissues Overview

  • Definition: Groups of cells with similar structure, function, and embryonic origin.

  • Importance: Tissue organization enhances efficiency and speed of body processes.

Categories of Tissues

  1. Epithelial Tissue

    • Covers body surfaces, lines cavities, forms glands.

    • Functions: Protects surfaces, secretes products, regulates material movement.

    • Structure: Cells show polarity (apical and basal surfaces).

  2. Connective Tissue

    • Connects tissues and organs, found throughout the body.

    • Components: Cells, matrix (ground substance), protein fibers.

    • Functions: Binds and supports tissues, protects organs, transports.

    • Types of Connective Tissue: Loose, dense, supportive (e.g., cartilage, bone), fluid (e.g., blood).

  3. Muscle Tissue

    • Enables movement.

    • Types:

      • Skeletal: Voluntary, striated, multiple nuclei.

      • Smooth: Involuntary, non-striated, spindle-shaped.

      • Cardiac: Involuntary, striated, branched, with intercalated discs.

  4. Nervous Tissue

    • Receives and processes information.

    • Components:

      • Neurons: Conduct electrical signals.

      • Neuroglia: Support neurons.

Structural Levels of Organization

  • Chemical Level: Atoms combine to form molecules.

  • Cellular Level: Cells consist of organelles and molecules.

  • Tissue Level: Similar types of cells form tissues.

  • Organ Level: Different tissues form organs.

  • Organ System Level: Organs work together in systems.

  • Organismal Level: Human body consists of multiple organ systems.