The term lacquer is used for a number of hard and potentially shiny finishes applied to materials such as wood. These fall into a number of very different groups.
Cardiac Muscle Tissue. Cardiac muscle tissue is an extremely specialized form of muscle tissue that has evolved to pump blood throughout the body. In fact, cardiac muscle is only found in the heart and makes up the bulk of the heartâs mass. The heart beats powerfully and continuously throughout an entire lifetime without any rest, so cardiac muscle has evolved to have incredibly high contractile strength and endurance.
Layers of the Heart. The heart consists of three layers in all. This Buzzle article explains the structure and function of each of these layers. The heart is one of the most important organs present in the human body. This organ is responsible for pumping blood to all parts of the body. Thus, it is considered as the main organ of the circulatory system. The heart is made up of specialized, smooth muscle tissue known as cardiac muscles or myocardium.