muscles in mammals

• Muscle fibers have a striated appearance due to their arrangement into sarcomeres.
• Sarcomere is the basic contractile unit of muscle, consisting of thick myosin filaments and thin actin filaments arranged in parallel.
• The sliding filament theory explains how contraction occurs through the interaction between myosin heads and actin binding sites.
• Myofibrils are made up of repeating units called sarcomeres, which contain thick (myosin) and thin (actin) filaments.