. how many parts is the human heart divided into?
With the average heart rate of 72 beats per minute the heart will pump about 5 litres per ventricle, or about 10 litres total per minute. This is called the cardiac output. In a trained athlete the total cardiac output is about 20 litres. If we multiply the normal, non-athlete output by the average age of 70 years, we see that the cardiac output of the average human heart over a life time would be about 1 million litres, or about 250,000 gallons(US)! The heart functions as a pump in the circulatory system to provide a continuous circulation of blood throughout the body. This circulation consists of the systemic circulation to and from the body and the pulmonary circulation to and from the lungs. The resting heart rate of a newborn can be 120 beats per minute (bpm) and this gradually decreases until maturity and then gradually increases again with age. The adult resting heart rate ranges from 60 to 100 bpm. That is, each time the heart contracts it does so with all its force. In skeletal muscles, the principle of gradation is present. The pumping of the heart is called the Cardiac Cycle, which occurs about 72 times per minute. This means that each cycle lasts about eight-tenths of a second. Make-up of the Heart. The walls of the heart are made up of three layers, while the cavity is divided into four parts. There are two upper chambers, called the right and left atria, and two lower chambers, called the right and left ventricles. The heart is a muscular organ in humans and other animals, which pumps blood through the blood vessels of the circulatory system. Blood provides the body with oxygen and nutrients, and also assists in the removal of metabolic wastes. The heart is located in the middle compartment of the mediastinum in the chest. Chambers and Valves. The heart is divided into four chambers: (see Figure 2). 1  right atrium (RA). 2  right ventricle (RV). 3  left atrium (LA). 4  left ventricle (LV). Commonly the right atrium and ventricle are referred together as the right heart and their left counterparts as the left heart. Fish in contrast have two chambers, an atrium and a ventricle, while reptiles have three chambers. It opens into the left ventricle and again is a one way valve. The left ventricle pumps the blood throughout the body. It is the Aorta, the largest artery in the body, which originates from the left ventricle. The Heart works as a pump moving blood around in our bodies to nourish every cell. 1 The tricuspid valve is at the exit of the right atrium. 2  The pulmonary valve is at the exit of the right ventricle. 3  The mitral valve is at the exit of the left atrium. 4  The aortic valve is at the exit of the left ventricle.
The heart is divided into four chambers.