Nervous And Connective Tissue

1. Nervous Tissue

Nervous tissue, forming the brain, spinal cord, and nerves, specializes in transmitting electrical messages throughout the body.

1.1 Components of Nervous Tissue

  • Neurons: Basic units transmitting electrical signals.

    • Parts: Cell Body (controls activities), Dendrites (receive impulses), Axon (carries impulses away), Myelin Sheath (insulates, speeds transmission), Synapse (junction for transmission).

  • Neuroglia: Support cells that protect, nourish, and insulate neurons without transmitting impulses.

1.2 Functions of Nervous Tissue

  • Transmits electrical signals rapidly for communication, coordination, and control, allowing the body to respond to stimuli.

2. Connective Tissue

Connective tissue provides support, connection, and protection, being the body's most abundant tissue.

2.1 General Characteristics

  • Cells: Widely scattered within an extracellular matrix.

  • Extracellular Matrix (ECM): Composed of Ground Substance (fluid/gel material) and Fibers (Collagen for strength, Elastic for stretch, Reticular for networks).

2.2 Functions of Connective Tissue

  • Binds tissues, provides structural support, protects organs, insulates (adipose), transports substances (blood), and stores energy/minerals.

2.3 Types of Connective Tissue

  • Loose Connective Tissue: Includes Areolar (binds skin/organs) and Adipose (stores fat, insulates, cushions).

  • Dense Connective Tissue: Densely packed fibers.

    • Dense Regular: Parallel fibers (tendons, ligaments) for strength in one direction.

    • Dense Irregular: Irregularly arranged fibers (dermis) for strength in multiple directions.

  • Specialized Connective Tissue: Includes Bone (support, protection, mineral storage), Cartilage (support, flexibility), and Blood (transports substances).