Our Circulatory System

We started our new topic by discussing which organs are part of our circulatory system and how oxygen, nutrients and water travel around our body: through our blood! 

We learnt that our heart is a pump made up of four chambers. The heart pumps deoxygenated blood, which is returning from the body via the vena cava, through to the lungs via the pulmonary to receive oxygen. The oxygenated blood then travels back to the heart via the pulmonary vein to be pumped around the body via the aorta. 

We then went out onto the playground to practise being the circulatory system ourselves! We learnt very quickly that it's quite hard work, pumping blood around the body! 

We also found out that our blood travels around our body via three main types of blood vessels: arteries, which have thick, elasticated walls and a pulse, and are used to carry blood from the heart to our organs. Veins, which have thinner walls and valves to stop blood from flowing backwards, carry blood back to the heart to be reoxygenated. Capilliaries are very small blood vessels, which travel through our organs.

Did you know? Blood is never actually blue! It is either a bright red when it contains lots of oxygen, or a deeper, purple-ish red when it contains less oxygen and more carbon dioxide.