MUSCLE PHYSIOLOGY

Detailed explanation-1: -Sarcomeres are considered as the most basic contractile units in muscles. They are made up of the contractile myofilaments (myosin and actin) and a series of structural proteins (e.g., titin, nebulin and desmin).

Detailed explanation-2: -There can be thousands of sarcomeres within a single muscle cell. Sarcomeres are highly stereotyped and are repeated throughout muscle cells, and the proteins within them can change in length, which causes the overall length of a muscle to change.

Detailed explanation-3: -A sarcomere is the basic contractile unit of a myocyte (muscle fibre). A sarcomere is composed of two main protein filaments (thin actin and thick myosin filaments) which are the active structures responsible for muscular contraction.

Detailed explanation-4: -Within the fasciculus, each individual muscle cell, called a muscle fiber, is surrounded by connective tissue called the endomysium.