What a smell!

2001/10/01 Ares, Felix Iturria: Elhuyar aldizkaria

• Anatomia/Fisiologia

The secret lies both in the smell of the female and in the nose of the male. The perfume that females emit to attract males is called pheromone. In fact, pheromones are emitted by many animal species, but the butterfly in particular is called ‘bambicol’.

Dogs are able to track people's footprint even if the person has spent several hours before. This is no wonder if we consider that dogs have 200 million odour cells. People have only five million.

It is said that hyenas are able to smell what is in a closed can. Do you think you could do something similar?

I propose an experiment for you to try! Put something odorous into a balloon and make a knot at the end so that no air comes out. Do you think you would be able to smell what is inside the globe?

The answer is yes, but it has a trick. Later I will explain what it is. To perform the test you need something smelling, a balloon and a box with lid. We have used vanilla powder, but you can use anything else in the house, such as aromatic herbs, perfumes... The box with lid can be the last purchased shoes. No matter the origin of the box.

To begin the experiment, take some odor substance and put it into the balloon. Inflate a little and make the knot at the end so that no air comes out.

Then clean the balloon, especially its face, to remove all signs of smell.

Then put the balloon inside the box and close it properly.

Wait about an hour. Open the lid of the box and smell the inside. Are there smells?

Close the box again and take it to another (parents or friends). Open the box a little and let them say what smells burn.

You will also be surprised, but you will see how all of you will have what is inside the globe, you too. How is it possible if the balloon is closed and you have cleaned the end? Would you smell what is inside a closed can like a hyena? No, our five million cells are insufficient. As we said before, there is a trick.

The problem is that the balloon is not completely airtight. In fact, on the surface of the globe there are invisible holes (pores) from which little by little the air particles and odorous matter go outside. That is why balloons are emptied.

The smell that has come out of the globe stays inside the box for a while, so you can smell and know what is inside the globe when opening the lid of the box.