The cardiovascular system
There are four major functions of the cardiovascular system, these include: the transportation of nutrients, gases and waste products around the body, the protection of the body from infections and blood …show more content…
To achieve this, the cardiovascular system is divided into two circuits- the pulmonary circuit and the systemic circuit. The pulmonary circuit consists of the heart, lungs and pulmonary veins and pulmonary arteries. This circuit’s role is to pump deoxygenated blood to from the heart to the lungs; it then becomes oxygenated blood and returns to the heart. It then pumps the oxygenated blood to the body’s tissues, muscles and organs which provides them with nutrients. Once the oxygenated blood has been delivered the systemic circuit it removes the carbon dioxide which becomes deoxygenated blood. It enters the lungs where it meets the pulmonary circuit to become oxygenated …show more content…
Internal respiration can be carried out inside the body cells by the respiratory system.
The respiratory system is responsible for controlling breathing. The thorax (chest) includes the lungs and their associated tubes, the bronchi and the heart, which are held in an airtight box. The air for breathing comes in contact with the thorax by the nose or the mouth. The nose is adapted for this function as well it is the recommended route.
The nose consists of fine bones which are placed on the side walls; they are a curled shape and are coated with a moist mucous membrane. These curled shape bones are rich in blood capillaries. This structure gives a large surface area for air to smoothly pass over, this makes well adapted to its function. The moist mucous membrane warms the air as it comes through the air passages, as it reaches the throat the air has almost become body temperature and has become moistened to the saturation point. The ciliated cells have filtered out most of the foreign bodies from the