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Right then kids, stay close please. We’re here in the park to find out about the human sense of smell. Let’s take a closer look at this fella, shall we?

Now smells are actually made up of tiny odour molecules carried in the air. Once these molecules make their way to a human’s nose, the business of smelling begins.

Careful now, children. Don’t get too close!

Ah, Jamie, what did I tell you!

Well, as long as you’re up there, you might as well take a look around.

All those hairs on the inside of the nose help to filter and clean the air before it goes down to the lungs.

Right at the back of the nose, there’s a small patch of skin covered in special sense receptors, which work in a similar way to the taste buds on the human tongue.

When odour molecules get there, they get trapped in a layer of mucus and dissolve. Once they’re dissolved, different odours cause different receptors to fire off signals to the brain through special nerves. The brain sorts out one smell from another based on whichreceptors have sent it signals.

Humans can usually tell the difference between about 10,000 different smells. But if they’ve got a bad cold, all that snot blocking their nose might stop them from being able to smell at all.

SNEEZING

Good to have you back Jamie! Now, let’s move along, shall we?

Children?

Ah… Well, that rubbish does smell rather delicious. Maybe just a quick rummage!