Structure of Cardiac Muscle

The labeled diagram of cardiac muscles shows its structure consisting of following points:

• Cardiac muscle fibers are connected by intercalated discs, acting like junctions. They allow for adhesion between cells and the passage of electrical impulses through structures like fascia adherens, desmosomes, and gap junctions.
• Fascia Adherens plays a very important role in the attachment of heart cells together .
• A gap junction forms channels between adjacent cardiac muscle fibers that allow the muscle cells to be electrically coupled, so that they beat in synchrony. The network of electrically connected cardiac muscle cells called a syncytium that enable the rapid transmission of electrical impulses through the network.
• Desmosomes (macula adherens) provide strong attachment by binding to the intracellular intermediate filaments/cytoskeleton during contraction.
• In the cardiac muscle there is also a sarcoplasmic reticulum ( store house of calcium), which is important for muscle contraction and relaxation.
• For the generation of impulses in the heart, pacemaker/ sinus node is present which causes the heart’s chamber to contract.
• From SA node , the impulses are transfers to the AV node and then conducted to the bundle of his , Purkinje fiber which spreads the impulses along the ventricles, causing them to contract.

The diagram of cardiac muscle shows the thick middle layer (myocardium) between the outer layer of the heart wall (the pericardium) and the inner layer (the endocardium). The diagram of cardiac muscle class 9 is often asked in the examinations. This muscle is crucial for pumping blood throughout the body and ensures oxygen and nutrients reach all the tissues and organs.

The diagram of cardiac muscle labeled is given below: