Movement

Tendons and ligaments

Tendons carry tensile forces from muscle to bone. They carry compressive forces when wrapped around bone. Tendons contain collagen fibrils, a proteoglycan matrix and fibroblasts cells arranged in parallel rows. They have blood supply. Ligaments connect bone to bone, and hold bones together.

Focus more on these understandings, applications and skills:

• Muscle fibers contain many myofibrils
• Each myofibril is made up of contractile sarcomeres
• The contraction of the skeletal muscle is achieved by the sliding of actin and myosin filaments
• ATP hydrolysis and cross bridge formation are necessary for the filaments to slide
• Calcium ions and the proteins tropomyosin and troponin control muscle contractions
• Antagonistic pairs of muscles in an insect leg
• Drawing labeled diagrams of the structure of a sarcomere
• Analysis of electron micrographs to find the state of contraction of muscle fibers

Questions related to these are:

• Describe the structure of a sarcomere.
• Explain the sliding filament theory.