Tissue types, components and functions 2/11 L.2
Components of Connective Tissue
Connective tissue has three main components:
Ground Substance
Fibers
Cells
Ground Substance
Comprises water and glycoaminoglycans (sugar-protein molecules).
Plays a vital role in maintaining the structural integrity of connective tissue.
Fibers
Fibers are proteins produced and secreted by cells, found in the extracellular matrix.
Types of fibers include:
Collagen Fibers
Formed from smaller protein subunits that wind together to create a helical structure.
Example: Achilles tendon, which can rupture.
Elastic Fibers
Allow tissue to stretch and recoil, working alongside collagen fibers.
Reticular Fibers
Short fibers that do not form strong or elastic networks.
Function as filters in various tissues.
Importance of Cell Types in Connective Tissue
Cells in connective tissue have distinct physical characteristics, determining their future functions.
The mesoderm layer holds significance as the common link for connective tissue types.
Key Terms
Blast Cells
E.g., chondroblast (produces cartilage), which is mitotically capable.
Differentiate into chondrocytes, located at the cartilage surface, while chondrocytes exist within the cartilage itself.
Bone Types
Two primary types of bone:
Compact Bone
Spongy Bone
Note: "Spongy" does not imply softness; all bone is hard.
Bone hardness results from collagen secretion followed by mineral deposition, cementing the structure.
Embryonic Development
Before birth, mesenchymal cells form embryonic connective tissue rich in ground substance.
Loose connective tissue is produced by fibroblasts, characterized by fibers and abundant ground substance.
Clinical Relevance
Injuries like meniscus tears in the knee often cause pain not from cartilage damage but from the damage to surrounding tissues with nerve endings.