8. Transport in mammals

8.1 The circulatory system

1. state that the mammalian circulatory system is a closed double circulation consisting of a heart, blood and blood vessels including arteries, arterioles, capillaries, venules and veins

2. describe the functions of the main blood vessels of the pulmonary and systemic circulations, limited to pulmonary artery, pulmonary vein, aorta and vena cava

3. recognise arteries, veins and capillaries from microscope slides, photomicrographs and electron micrographs and make plan diagrams showing the structure of arteries and veins in transverse section (TS) and longitudinal section (LS)

4. explain how the structure of muscular arteries, elastic arteries, veins and capillaries are each related to their functions

5. recognise and draw red blood cells, monocytes, neutrophils and lymphocytes from microscope slides, photomicrographs and electron micrographs

6. state that water is the main component of blood and tissue fluid and relate the properties of water to its role in transport in mammals, limited to solvent action and high specific heat capacity

7. state the functions of tissue fluid and describe the formation of tissue fluid in a capillary network

8.2 Transport of oxygen and carbon dioxide

1. describe the role of red blood cells in transporting oxygen and carbon dioxide with reference to the roles of:

• haemoglobin

• carbonic anhydrase

• the formation of haemoglobinic acid

• the formation of carbaminohaemoglobin

2. describe the chloride shift and explain the importance of the chloride shift

3. describe the role of plasma in the transport of carbon dioxide

4. describe and explain the oxygen dissociation curve of adult haemoglobin

5. explain the importance of the oxygen dissociation curve at partial pressures of oxygen in the lungs and in respiring tissues

6. describe the Bohr shift and explain the importance of the Bohr shift

8.3 The heart

1. describe the external and internal structure of the mammalian heart

2. explain the differences in the thickness of the walls of the:

• atria and ventricles

• left ventricle and right ventricle

3. describe the cardiac cycle, with reference to the relationship between blood pressure changes during systole and diastole and the opening and closing of valves

4. explain the roles of the sinoatrial node, the atrioventricular node and the Purkyne tissue in the cardiac cycle (knowledge of nervous and hormonal control is not expected)