GENERAL HISTOLOGY

Detailed explanation-1: -A muscle contracture, also known as a contracture deformity, is a permanent shortening and tightening of muscle fibers that reduces flexibility and makes movement difficult. It is caused when a muscle loses elasticity. If a muscle cannot move and be stretched, the nearby joints also lose mobility and become painful.

Detailed explanation-2: -Sliding filament model of contraction. For a muscle cell to contract, the sarcomere must shorten. However, thick and thin filaments-the components of sarcomeres-do not shorten. Instead, they slide by one another, causing the sarcomere to shorten while the filaments remain the same length.

Detailed explanation-3: -A concentric contraction causes muscles to shorten, thereby generating force. Eccentric contractions cause muscles to elongate in response to a greater opposing force. Isometric contractions generate force without changing the length of the muscle.