Types of Joints in the Human Body

Types of Joints

• Cartilaginous Joints: made of cartilage, little to no movement
• Synchondroses: immovable joints, found in epiphyseal plate or joints between ribs and sternum
• Symphysis: slightly movable joints, found in intervertebral discs and pubic symphysis
• Synovial Joints: freely movable joints, characterized by articular cartilage and synovial membrane

Synovial Joints

• Articular cartilage: reduces friction, absorbs shock
• Articular capsule: surrounds joint, has thickenings in fibrous capsule
• Synovial membrane: inner lining of capsule, secretes synovial fluid, brings nutrients to articular cartilage

Types of Synovial Joints

• Saddle joint: one bone is saddle-shaped, the other bone fits into it
• Condyloid joint: oval-shaped projection fits into oval depression, allows for flexion, extension, abduction, and adduction
• Pivot joint: rounded surface of bone articulates with ring formed by 2nd bone and ligament, allows for supination and pronation
• Hinge joint: convex surface of one bone fits into concave surface of 2nd bone, allows for flexion and extension
• Ball and socket joint: allows for rotation, revolve around its own longitudinal axis

Muscle Properties

• Conductivity: ability to propagate electrical signals over membrane
• Contractibility: ability to shorten and generate force
• Extensibility: ability to be stretched without damaging the tissue
• Elasticity: ability to return to original shape after being stretched

Connective Tissue Components of Muscle

• Endomysium: surrounds individual muscle cells
• Perimysium: surrounds bundles of muscle cells
• Epimysium: surrounds the whole muscle

Muscle Fibers

• Sarcolemma: muscle cell membrane, made of lipids
• Sarcoplasmic reticulum (SR): stores calcium, releases it to trigger muscle contraction
• T-tubules: extensions of the sarcolemma, carry sodium ions
• Mitochondria: lies in rows throughout the cells, uses ATP during muscle contraction

Muscle Action Potential

• Excitability: ability to respond to chemicals released from nerve cells
• Muscle action potential: flow of sodium ions through t-tubules

Types of Joints

• Cartilaginous Joints: made of cartilage, little to no movement
• Synchondroses: immovable joints, found in epiphyseal plate or joints between ribs and sternum
• Symphysis: slightly movable joints, found in intervertebral discs and pubic symphysis
• Synovial Joints: freely movable joints, characterized by articular cartilage and synovial membrane

Synovial Joints

• Articular cartilage: reduces friction, absorbs shock
• Articular capsule: surrounds joint, has thickenings in fibrous capsule
• Synovial membrane: inner lining of capsule, secretes synovial fluid, brings nutrients to articular cartilage

Types of Synovial Joints

• Saddle joint: one bone is saddle-shaped, the other bone fits into it
• Condyloid joint: oval-shaped projection fits into oval depression, allows for flexion, extension, abduction, and adduction
• Pivot joint: rounded surface of bone articulates with ring formed by 2nd bone and ligament, allows for supination and pronation
• Hinge joint: convex surface of one bone fits into concave surface of 2nd bone, allows for flexion and extension
• Ball and socket joint: allows for rotation, revolve around its own longitudinal axis

Muscle Properties

• Conductivity: ability to propagate electrical signals over membrane
• Contractibility: ability to shorten and generate force
• Extensibility: ability to be stretched without damaging the tissue
• Elasticity: ability to return to original shape after being stretched

Connective Tissue Components of Muscle

• Endomysium: surrounds individual muscle cells
• Perimysium: surrounds bundles of muscle cells
• Epimysium: surrounds the whole muscle

Muscle Fibers

• Sarcolemma: muscle cell membrane, made of lipids
• Sarcoplasmic reticulum (SR): stores calcium, releases it to trigger muscle contraction
• T-tubules: extensions of the sarcolemma, carry sodium ions
• Mitochondria: lies in rows throughout the cells, uses ATP during muscle contraction

Muscle Action Potential

• Excitability: ability to respond to chemicals released from nerve cells
• Muscle action potential: flow of sodium ions through t-tubules