Reflexes

A reflex happens automatically. When a person touches a candle flame, impulses travel along the nerve to the spinal cord. The message reaches the muscles, which pull the arm back.

📖 In short

A reflex is a quick movement your body makes by itself, without you thinking about it! If you touch something hot, you pull your hand away at once, before you even think. These actions protect you from danger.

🤩 Did you know?

Reflexes are faster than movements we think about.
A baby grips your finger tightly if you put it in its palm, and that's a reflex.
The Russian scientist Ivan Pavlov studied learned responses.
Yawning is one of the things that happen without us meaning to.

🔎 Find out more

🌟 A shortcut

Usually messages travel from the body to the brain, which decides what to do. But in a reflex, the message reaches the spinal cord, which sends the order straight to the muscles, and that's much faster.

🔍 Lots of examples

Your eye blinks if something comes near it, your pupil shrinks in bright light, you sneeze if dust gets in your nose, and you cough if something gets in your throat. They're all reflexes.

💡 The doctor's hammer

Sometimes the doctor taps your knee with a little hammer, and your leg kicks up by itself. That's how they check your nerves are working well.

🎯 Learned responses

Some responses are learned over time. The scientist Pavlov noticed that a dog drools when it hears a bell if it's used to hearing it before food.

🧩 Test yourself

1 What do you do if you touch something hot?

2 Which of these is a reflex?

3 Which picture shows “Reflexes”?