The Circulatory System
The circulatory system pumps blood around the body through the heart and blood vessels, delivering oxygen and nutrients.
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The circulatory system pumps blood around the body through the heart and blood vessels, delivering oxygen and nutrients.
- It is a double circulation
- Arteries carry blood away from the heart
- Veins return blood to the heart
🧠 Quick quiz
Three questions. Score 2 or more to complete the topic.
What is The Circulatory System?
Within Biology, which covers cells, the human body, genetics, evolution, plants and ecosystems: the science of living things, this topic explains The Circulatory System. Biology topics show how living things work, from the cell up to whole ecosystems, with models you can explore step by step.
Check that you can explain The Circulatory System in your own words and give one example from everyday life. If you can do that, you have understood the core idea.
Understanding The Circulatory System helps you explain how living things stay alive and respond to their surroundings, which is central to biology exams.
The Circulatory System in detail
The circulatory system transports substances around the body: oxygen, carbon dioxide, nutrients, hormones and waste. Humans have a double circulatory system: the pulmonary circuit takes blood from the heart to the lungs and back, and the systemic circuit takes blood to the rest of the body and back.
A double system keeps oxygenated and deoxygenated blood separate and allows blood to be pumped at high pressure to the body after it has been through the lungs. The heart is the pump, and blood vessels carry blood. Transport allows large animals to supply their cells quickly because diffusion alone would be too slow.
How the interactive helps you understand The Circulatory System
Watch the heart model in the interactive. Use any sliders or buttons it offers to change the values and see how the heart model responds.
Before you change anything, predict the result. Then change one value at a time and check whether your prediction was right. This is a quick way to build a correct mental model of The Circulatory System.
Real-life uses and examples
- Structure a longer answer about The Circulatory System by moving from definition to example to consequence.
- Explain how The Circulatory System helps a living thing stay alive, using a plant or animal example.
- Connect The Circulatory System to health, food and medicine in everyday life.
Common mistakes to avoid
- Listing the steps of a process without saying how one step causes the next.
- Using everyday words, such as “energy” or “bad”, without their scientific meaning.
- Learning the definition without testing it. Use the quiz and the interactive to check that you can apply the idea.
Frequently asked questions about The Circulatory System
What is The Circulatory System?
The circulatory system pumps blood around the body through the heart and blood vessels, delivering oxygen and nutrients.
What are the most important points about The Circulatory System?
The main points are: It is a double circulation; Arteries carry blood away from the heart; Veins return blood to the heart.
Why is The Circulatory System useful?
Understanding The Circulatory System helps you explain how living things stay alive and respond to their surroundings, which is central to biology exams.
How can I practise The Circulatory System?
Open the interactive at the top of this page and change the controls one at a time. Predict the result before each change, then take the three-question quiz. A score of two or more marks the topic as complete on this device.
Which topics are related to The Circulatory System?
Related topics in Biology include Blood and Its Components, The Immune System, Non-Communicable Diseases.