Circulatory systems
Introduced| English | Meaning |
|---|---|
| circulatory system/ˌsɜːkjʊˈleɪtəri ˈsɪstəm/ | The heart, blood and blood vessels that transport substances around the body. |
| double circulation/ˈdʌbl ˌsɜːkjʊˈleɪʃn/ | A system in which blood passes through the heart twice in a complete journey through the lungs and body. |
| pulmonary/ˈpʌlmənəri/ | pulmonary |
| systemic/sɪˈstemɪk/ | systemic |
The body's delivery network
- Your cells need a constant supply of oxygen and food, and a way to remove waste.
- The circulatory system 循环系统 — heart, blood and vessels — delivers it all.
In a double circulation, blood passes through the heart:
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Double circulation means two passes through the heart.
A double circulation 双循环
- Humans have a double circulation: blood passes through the heart twice per full circuit.
- One loop goes to the lungs (to pick up oxygen); the other goes to the body.
In a double circulation the blood passes through the heart twice on each trip round the body
Double circulation
Mammals have a double circulation — blood passes through the heart TWICE on each full trip round the body.
The pulmonary circulation carries blood between the heart and the:
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Pulmonary = to the lungs for oxygen.
The circulation that carries blood to the body (not the lungs) is the ______ circulation.
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Systemic = to the body; pulmonary = to the lungs.
The two loops
- Pulmonary 肺的 circulation: heart → lungs → heart (gets oxygen).
- Systemic 体循环的 circulation: heart → body → heart (delivers oxygen).
A benefit of double circulation is that blood reaching the body is:
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Re-pressurising the blood speeds delivery.
Fish have a double circulation, while mammals have a single circulation.
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False. It is the other way round: fish have a single circulation, while mammals pump blood through the heart twice per circuit (double circulation).
Why double is better
- A double circulation lets blood be re-pressurised before going to the body.
- This delivers oxygen faster — important for active animals like mammals.
Fish have a single circulation; mammals have a double one. In a double circulation blood is pumped twice, keeping pressure high to the body. This supports a faster, more active lifestyle.
You've got it
- the circulatory system delivers oxygen/food and removes waste
- humans have a double circulation (blood through the heart twice per circuit)
- pulmonary loop = lungs; systemic loop = body; double = higher pressure, faster delivery
Write from two passes through the heart
- Blood from the body enters the heart and is sent to the lungs.
- It returns to the heart before it is sent to the body again.
What kind of circulation is this, and what is the lung loop called?
Two loops mean two visits to the heart.
Which loop sends blood to the lungs?
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Pulmonary means the lung circuit.