The Role Of Cardiac Muscles In The Human Body

The heart is one of the strongest muscles in the human body. It is mostly made up of cardiac muscle, which causes the contractions of the heart, or heartbeat. The cardiac muscle works constantly to pump blood throughout the body and is one of the three major types of muscle. The cells in the heart are closely connected so that they all beat at the same time, and they form the thick middle layer of the heart, in between the outer epicardium and the inner endocardium layers. There are two main functions of cardiac muscle cells. They are cardiomyocytes and cardiac pacemaker cells. Cardiomyocytes make up the atria and ventricles, where blood is brought into the heart, collected, and moved out of the heart. They are able to stretch to allow the muscle to contract. Pacemaker cells are responsible for the beating heart. They are able to receive electrical impulses from the brain and move them throughout the heart cells, causing cardiomyocytes to contract, and the heart to beat. Pacemaker cells receive signals from the nervous system telling them to cause the heart rate to increase or decrease depending on what the body needs. They move electrical impulses through the heart about 70 times a …show more content…
The cells contain one nucleus, but many mitochondria. That is because the heart beats constantly from birth until death, if no complications occur, and that uses an incredible amount of energy. The mitochondria provide energy, ATP, to the cells so that they are able to function at the necessary rate. At the end of each cell is an area of extensions of the membrane, called intercalated disks. These disks create tight junctions so that the cells cannot separate under the strain of contracting and pumping blood. The gap junctions in the heart exist so that the electrical impulses can be transmitted rapidly throughout the