Biology Topic 2

The body - the vena cava - the right atrium - the right ventricle - the tricuspid valve - semi-lunar/pulmonary valve - pulmonary artery - the lungs - the pulmonary veins - bicuspid valve - the left ventricle - semi-lunar/aortic valve - the aorta - the body. 

Word equations

Respiration-   Carbon Dioxide + Water = Oxygen + Glucose 

Photosynthesis- Oxygen + Glucose = Carbon Dioxide + Water

Balanced symbol equations

Respiration- C02 + H20 = O2 + C6H12O6  

Photosynthesis- O2 + C6H12O6 = CO2 + H20 

(Highlighted numbers are small numbers after the chemical symbol)

• Veins carry the deoxygenated blood into the heart - Vein enters through the vena cava 
• Larger veins have valves to ensure the blood flows in one direction
• Although most veins carry deoxygenated blood the pulmonary vein and the umbilical vein carry blood that is high in oxygen 
• The blood in veins is dark red but can appear to be blue because of the scattering of light through the skin. 

• Deliver oxygenated blood to the body from the heart
• Are a muscular tube with smooth tissue and has got three layers
• Carry blood away from the heart - Arteries=away  
• The only arteries that do not carry oxygenated blood are the pulmonary artery and the umbilical artery (in a fetus)
• Blood in the arteries is under high pressure

• It is a very small blood vessel that has a cell wall that is one cell thick
• Their function is to allow food and oxygen to diffuse to the cells while the waste is diffused from the cells  
• They are the smallest blood vessels in the body 
• They take oxygen from the arteries and take it to the tissues and they then take the waste products, such as deoxygenated blood, to the veins.