Joints, Muscles

• Function: amount of movement
• or
• Structure: material that binds the bones together

• 1) Synarthroses
• 2) Amphiarthroses
• 3) Diarthroses

Functional Classification of Joints. Synarthroses are immovable joints.

Functional Classification of joints. Amphiarthroses are slightly moveable joints.

• Functional Classification of Joints.
• Diarthroses are freely moveable joints. Predominant in the limbs.

• 1) Fibrous
• 2) Cartilaginous
• 3) Synovial

Bones are connected by fibrous tissue, mainly DRCT. No joint cavity present. Most are immoveable. Sutures, syndemoses (interosseous membrane between radius and ulna), gomphoses (tooth).

Articulating bones are united by cartilage. Lack a joint cavity, not highly moveable. Two types: Synchondroses (hyaline cartilage unites bones) and symphyses (epiphyseal plates).

• "Joint Eggs"
• Most moveable joints of the body. Contains a fluid filled joint cavity.

• 1) Articular cartilage
• 2) Joint cavity
• 3) Articular Capsule
• 4) Synovial Fluid
• 5) Reinforcing Ligaments
• 6) Nerves and Vessels

• 1) Shapes of articular surfaces
• 2) Number and position of stabilizing ligaments
• 3) Muscle tone

• Bursa is a flattened fibrous sac lined with synovial membrane. Occures where ligaments, muscles, skin, tendons or bones overlie each other.
• Tendon Sheath is an elongated bursa that wraps around a tendon like a bun around a hot dog.

• 1) Gliding, such as in carpals and tasals and between the flat articular processes of the vertebrae.
• 2) Angular Movements, increase or decrease the angle of two bones. Includes flexion, extension, absuction, adduction and cicumduction.
• 3) Rotation, turning mocement of a bone, such as between the first two cervical vertebrae.

• Supination and Pronation refer to movements of the radius and ulna.
• Supination occurs when forearm ratates laterally so that the palm faces up. "Sup, give me five" (haha)
• Pronation occurs when forearm rotates medially so palm faces down.

Synovial joint where the articular surfaces are flat planes.

• Synovial Joint
• Cylindrical end of one bone fits into trough shaped surface on other bone.
• Elbow and Ankle

• Synovial Joint
• Rounded end of one bone fits into a ring that is formed by another bone plus an encircling ligament.
• Example: joint between atlas and the dens of the axis.

• Synovial joint
• Egg shaped articular surface fits into oval concavity. Allows bone to travel 1) side to side 2) back and forth.

Synovial Joint with both convex and Concave areas like a saddle.

• Synovial Joint
• Spherical head of one bone fits into a round socket of another.

• 1) Movement
• 2) Maintenance of posture
• 3) Joint Stabilization
• 4) Heat Generation

• 1) Skeletal Muscle
• 2) Cardiac Muscle
• 3) Smooth Muscle

• 1) Epimysium - Overcoat of DICT
• 2) Perimysium - Surrounds each fascicle (muscle fibers grouped into bundles of 'sticks')
• 3) Endomysium - Within a fascicle, each muscle fiber is surrounded bu a fine sheath of CT reticular.

Striations of long rod shaped organelles called Myofibrils within the sarcoplasm. Myofibrils are unbranched cylinders.

• Sarcomeres are repeating segments in a myofibril.
• The Sarcomere is the basic unit of contraction in teh skeletal muscle.

I bands

A bands

Z discs

H zone

Thin (actin) filament

Thick (myosin) filament

Elastic (titin) filaments

Z discs

M line

• Describes the mechanism of skeletal muscle contraction.
• Myosin heads of the thick filaments attach to thin filaments at both ends of the sarcomere and pull the thin filaments towards the center of teh sarcomere. Myosin will "hinge", then it will "recock" and bing to the thin filament farther along its length.

Spring like molecure in sarcomeres that resists overstretching.

Deep invaginations on the sarcolemma that run between the cisternae of the sarcoplasmic reticulum.