Identify the types of structural and functional joints

Structural types of joints (based on the structure):
1. Synovial joints - the most common and the most moveable type of joints, characterised by joint capsule around the joint and synovial fluid inside of it )(Examples: shoulder, elbow, wrist, hip, knee...)
2. Cartilaginous joints - connected by hyaline or fibrocartilage and consequently less mobile than synovial joints (Example: intervertebral discs in the spinal cord)
3. Fibrous joints - non-moveable joints made of dense connective tissue (Example: joints between the bones of the skull)

Functional type of joints (based on the degree of movement):
1. Diarthrosis - the most moveable joints
2. Amphiarthrosis - the less moveable joints
3. Synarthrosis - the non-moveable joints

The answer is nucleic acid 

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