The Circulatory and Respiratory Systems

Learning Goals By the end of this unit you should be able to: Identify and describe the main functions of the circulatory and respiratory system Identify and describe the different types of blood cells and give examples of their function Identify how the circulatory and respiratory systems affect performance and participation levels Understand how activity and exercise develop and effect the efficiency of the circulatory and respiratory systems Understand the difference between aerobic and anaerobic activity

The Circulatory System The circulatory system involves the heart, blood vessels and blood. Its functions are Transport of oxygen and nutrients. Remove waste Control body temperature Protect and fight disease

The circulatory system The heart is the pump in a double circulatory system. The pulmonary circuit carries deoxygenated blood from the heart to the lungs. The systemic circuit carries oxygenated blood from the heart to the rest of the body.

The Circulatory System There are three types of blood vessels in the circulatory system. ARTERIES – these carry blood away from the heart, work under high pressure and are thick and elastic. Usually carry OXYGENATED blood VEINS – these carry blood to the heart, work at a lower pressure, have valves, thinner walls and are less elastic. Usually carry DEOXYGENATED blood CAPILLARIES – the smallest of all blood vessels with walls one cell thick to allow nutrients to pass through one way and waste another.

The Circulatory System BLOOD Blood is the transport system of the body. It carries materials from one organ to another. It takes oxygen from the lungs to the heart and then to the tissues. It takes carbon dioxide from the tissues to the heart and then to the lungs. It also takes soluble food from the intestines and waste products from the kidneys.

Blood Red blood cells. (Erythrocytes) Millions of cells float in yellowish liquid called plasma. They are disc shaped and orange but in a large mass appear red. The pigment that gives them the red colour is called haemoglobin. This attracts oxygen. It picks up the oxygen in the lungs and delivers it to the tissues. One cubic millimeter of healthy blood contains about 5 million red cells.

Blood Blood Plasma It is pale-straw coloured liquid consisting of 90% water. It contains inorganic salts, glucose, antibodies, urea and other waste products. It also contains substances that are important for maintaining circulation between cells and tissues called plasma proteins

Blood White blood cells. (leukocytes) They have an important function and the defence system of the body as they destroy pathogens which cause disease. Some of these cells completely engulf bacteria or viruses in the blood to digest them others destroy pathogens with chemicals called antibodies

Blood Blood Platelets.   These are tiny specialized particles that are actives whenever blood clotting or repair to vessels is necessary. They are made in the bone marrow and are much smaller than red blood .

Factors that affect blood Living at altitude - . People born at high altitude where there is less oxygen have a higher cell count. This means that when they come down to a lower altitude they are able to transport more oxygen to their muscles. This is beneficial to aerobic sports like long distance running. Anemia - Hemoglobin contains iron and its lack of iron that causes anemia. A low cell count causes you to be breathless and lacking in energy. This will in turn affect how effective you are doing sport. Haemophilia – a hereditary genetic disorder that impair the body's ability to control blood clotting, which is used to stop bleeding when a blood vessel is broken. Being a hemophiliac will restrict participation in sport incase injury occurs.

The Respiratory System The respiratory system involves the air passages, lungs and diaphragm. Its functions are Help get oxygen into the body Remove carbon dioxide and waste products

The Respiratory System Air passages A series of linking tubes that create a pathway for air to get into the lungs. When air enters through the nose it is warmed There are hairs and mucus in the nose which filter the air stopping larger particles of dust getting into the lungs. The nose also moistens the air so it can be absorbed by the alveoli more easily

The Respiratory System The Lungs Positioned in the chest cavity and protected by the ribs. Breathing means that the lungs constantly move in and out. Air enters the lungs from the trachea. This splits into two bronchi which subdivide into smaller bronchioles. At the end of bronchioles are alveoli which are air sacs covered in capillaries. It is here gaseous exchange takes place.

The Respiratory System The Diaphragm A sheet of muscle dividing the chest cavity and abdominal cavity. When we breathe in – inspiration – the diaphragm pulls down enabling air to be sucked in. When we breathe out – expiration – the diaphragm relaxes into a dome position reducing chest size and forcing air out.