Connective Tissue
Connective Tissue Cell: A connective tissue cell is one of the four basic cell types (connective tissue, epithelial, muscle cells, and nerve cells). There are many types of specialized connective tissue cells, but their primary role is in supporting, protecting, transmitting force, and exchanging nutrients for other cells in the body. For example, muscle cells are enclosed by a layer of connective tissue known as the "epimysium," bundles of muscle cells known as fascicles are enclosed by a layer of connective tissue known as the "perimysium," and bundles of fascicles are bound to form muscles that are enclosed in a layer of connective tissue known as the "endomysium."
For more information on the epimysium, perimysium, and endomysium, check out:
Examples of Connective Tissue
- Loose Connective Tissue
- Areolar Tissue: Found under the skin, around organs, and surrounding muscle cells , it provides shock absorption and some protection and is a medium for nutrient and waste exchange.
- Adipose Tissue: Adipose tissue, commonly referred to as "fat cells," stores energy, aids in insulating the body, and protects/cushions organs.
- Reticular Tissue: This is connective tissue that creates a supportive framework in soft organs like the liver, spleen, and lymph nodes.
- Dense Connective Tissue
- Dense Regular Tissue: These are strong fibers arranged primarily in parallel and are found in tendons, ligaments, and fascial sheaths
- Dense Irregular Tissue: This is connective tissue with a higher proportion of collagen fibers arranged in a more random pattern, found in the dermis of the skin and the capsules around organ capsules. They add resistance to stretch.
- Elastic Tissue: This is connective tissue that contains a higher proportion of elastin fibers, resulting in more extensibility and elasticity, and can be found in large arteries and the lungs.
- Cartilage
- Hyaline Cartilage is a specialized type of smooth, glass-like connective tissue found on the surfaces of synovial joints , the nose, and the trachea. It permits smooth movement and structural support.
- Elastic Cartilage: This is a flexible type of cartilage found in structures like the ear and epiglottis.
- Fibrocartilage: Fibrocartilage is a dense and strong type of connective tissue found in the intervertebral discs, knee menisci, shoulder labrum, hip labrum, etc. It extends the lip of joint sockets, providing stability and shock absorption for the adjoining bones.
- Bone (Osseous Tissue)
- Bone is a type of specialized connective tissue. The skeleton gives us shape and supports motion, protects organs and other sensitive tissues, and stores calcium and phosphorus.
- Blood
- Blood is also a type of connective tissue cell. It transports nutrients, gases, waste, and is an integral part of the immune system.