Muscle cells in the heart
The heart is made up of cardiac muscles, which means that the heart will never get tired. The heart contains myocytes cells. The function of the myocytes is to contract and pump the blood from the heart to the lungs. Located at the right atrium of the heart, there is a group of cells, which is called the Sino atrial node. The Sino atrial node produces and releases electrical impulses, which ensure that the heart contracts and pumps the blood to the whole circulatory system. This happens by the myocytes cells contracting. The cardiac muscle cells contain intercalated discs, which allows multiple cardiac muscle cells to contract. The cardiac cells also contain ions such as potassium and calcium; these ions would usually be exchanged by one ion getting replaced with a similar ion. These ions help regulate the duration and strength of the contractions that occur in the heart.
The cardiac muscle cells also have a unique shape, the shape the cardiac muscle has is a y shape. This is because the cardiac muscle has branches and fibers that are striated. These cells contain nuclei. When compared to the smooth muscles, the smooth muscles are linear whereas the cardiac muscle cells have a network of fibers. The main reason why the fibers of the cardiac muscle cells are all joined together is because they form a mesh which enables the it to squeeze the blood out of the heart to the rest of the circulatory system and the rest of the body. If the mesh stops function such as the contractions stopping then this will result in the individual suffering from cardiac arrest.
The muscle cells in the arms and legs
The body has skeletal cells, which are all around the body, this includes the arms and the legs. If a muscle provides movement then also another muscle provides opposite movement. For example, when you are curling your arm up towards your shoulder, your biceps will be moving but also the triceps would be too. There are two main muscle movements, antagonistic and agonist. Antagonist movement is when a muscle is relaxed while the opposite muscle contracts. Agonist movement is when a muscle contracts. For example, when you tense your bicep, the bicep is agonist and the triceps is antagonist. The main features of the antagonist muscles help stabilize and control the motion when the movement occurs. The triceps consists 3 tendons which one is attached to the scapula like the bicep and the other 2 are attached to the back of the humerus, the humerus is a bone which holds the bicep and triceps.
The bicep is attached...