Capsule

Capsule (Anatomy)

A capsule in anatomy refers to a membranous structure that encloses an organ, joint, or other body part. Capsules are typically composed of dense connective tissue and serve to protect and support the enclosed structures.

Types of Capsules

Capsules can be classified based on their location and function within the body. The primary types include:

Joint Capsules

Joint capsules, also known as articular capsules, surround synovial joints. They consist of two layers: an outer fibrous layer and an inner synovial membrane. The fibrous layer provides structural support, while the synovial membrane secretes synovial fluid to lubricate the joint.

Organ Capsules

Organ capsules are found surrounding various organs, providing protection and structural integrity. Examples include:

• The renal capsule surrounding the kidneys.
• The Glisson's capsule surrounding the liver.
• The splenic capsule surrounding the spleen.

Bacterial Capsules

In microbiology, a capsule refers to a gelatinous layer surrounding certain bacteria. This capsule helps protect bacteria from phagocytosis and can enhance their ability to cause disease.

Functions of Capsules

Capsules serve several important functions in the body:

• **Protection**: Capsules protect enclosed structures from physical damage and infection.
• **Support**: They provide structural support, maintaining the shape and position of organs and joints.
• **Lubrication**: In joints, the synovial membrane of the capsule secretes synovial fluid, reducing friction and allowing smooth movement.

Related Pages

• Connective tissue
• Synovial joint
• Renal capsule
• Glisson's capsule
• Splenic capsule
• Phagocytosis