Where does this come from, and can I check it?

Sympathetic nerves mobilise the body for action while parasympathetic nerves restore calm. The figure is taken from Encyclopaedia Britannica, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.

Is this really a human body fact?

Yes. It sits on the Human Body shelf, one of 2,600 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.

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The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.

Mondo Knows Facts

The autonomic system has accelerator and brake branches

Sympathetic nerves mobilise the body for action while parasympathetic nerves restore calm Both branches use two neurons in series, with acetylcholine at the first synapse. The sympathetic branch then releases noradrenaline at target organs, speeding the heart and widening the pupils. The parasympathetic branch releases acetylcholine, slowing the heart and promoting digestion. It sits in Mondo's human body collection, one of 200 facts that each trace back to the reference below.

Where this comes from

Encyclopaedia Britannica

Facts that can change over time are reviewed and updated. If something here looks wrong, Mondo would rather know than be confidently incorrect.

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Tags: nerves, autonomic, heart

The autonomic system has accelerator and brake branches: the short answers

Where does this come from, and can I check it?: Sympathetic nerves mobilise the body for action while parasympathetic nerves restore calm. The figure is taken from Encyclopaedia Britannica, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
Is this really a human body fact?: Yes. It sits on the Human Body shelf, one of 2,600 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.
What else can I read about it?: The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.