Skeletal Muscle, Synovial Joints, and Cartilage Vocabulary

Vocabulary flashcards based on lecture notes about skeletal muscle architecture, synovial joints, cartilage, and synovial fluid.

Pennation Angle

The angle between the muscle fibers and the line of pull of the muscle. It increases with hypertrophy.

Hypertrophy

Increase in the size of a muscle due to an increase in the size of its cells.

In-Series Sarcomere Addition

The addition of sarcomeres along the length of a muscle fiber. Human Fiber Lengths change ~10-15% changes w/ 2-4w eccentric / concentric training (faster in rats).

In-Parallel Sarcomere Addition

The addition of sarcomeres alongside each other in a muscle fiber, increasing the muscle's cross-sectional area.

Synovial Joint

A type of joint that has synovial fluid, cartilage, a joint capsule, a synovial membrane, and ligaments, allowing for relatively large range of motion (ROM).

Synovial Fluid

A viscous fluid found in synovial joints that lubricates the joint, provides nutrients to cartilage, and contains hyaluronate and lubricin.

Cartilage

A type of connective tissue found in joints that provides a low-friction surface for movement and distributes load.

Chondroblast

A metabolically active cell that produces the matrix of cartilage.

Chondrocyte

A mature cartilage cell with significantly less metabolic activity, that is found within the cartilage matrix.

Articular Cartilage (Hyaline)

A type of cartilage that covers the ends of bones in synovial joints, providing a smooth, low-friction surface for movement.

Extracellular Matrix (ECM)

The network of collagen (type II), proteoglycans, and water that surrounds chondrocytes in cartilage.

Proteoglycans

Components of the extracellular matrix in cartilage that attract and retain water, providing resistance to compression.

Anisotropic Behavior

Having properties that vary depending on the direction in which they are measured, as seen in articular cartilage due to collagen fiber orientation.

Osteoarthritis (OA)

A degenerative joint disease characterized by the breakdown of cartilage.

Thixotropy

The property of synovial fluid that causes it to become less viscous when experiencing shear stress.

Lubricin

A glycoprotein present in synovial fluid that contributes to joint lubrication.