why do we have two kidneys so that we can only live with one?

Curious Kids is a children's series. If you have a question that you would like an expert to answer, send it to [email protected] You might also like the Imagine This podcast, a coproduction between ABC KIDS Listen and The Conversation, based on Curious Kids.

Why do we have two kidneys so that we can only live with one? – Question from Ms. Morris Grade 5 students, Ringwood North Elementary School, Victoria.

This is a very good question. The answer is that scientists are not completely sure but we have some theories. This is often the case with science.

Most of the animals you see above the ground on Earth today, including humans, are the same on both sides. We have two eyes, two ears and even two nostrils. Scientists have given this name a fancy name called "bilateral symmetry".

If you look in the mirror and draw an imaginary line in the middle of your reflection, you will see that you have one arm and one leg on each side. If you had glbades that allowed you to see your interior, you would see that you also have a kidney and a lung on each side.

But it was not always like that. And some animals always have only one kidney.

About 500 million years ago, our long lost parents who lived in the ocean (some of whom probably had only one kidney) decided to leave the water to walk and live on the ground.

This was a very important moment in our history because on the mainland, the animals could change to form a very complicated body with all the important organs that are inside you, including two kidneys.

Read more:
Curious Kids: How does my belly turn food into poop?

Two kidneys better than one?

At the moment, your kidneys are getting rid of everything your body does not need. They do it by "cleaning" your blood.

All this waste will come out of your body when you go to the toilet. But your kidneys do a lot more than just clean your blood. They help your bones stay healthy, tell your body when to make new blood cells, and even help you stay upright when you walk all day taking care of your blood pressure.

With all these important functions, the scientist thinks that having two kidneys must be important for our survival.

Grow with a kidney

That's right you can live with one kidney. Some people are born with one because the other has not grown up well. On other occasions, the two kidneys touch each other when they first grow up and join together, thus forming one of the horseshoe-shaped kidneys. People with this type of kidneys must be very careful because they may fall more easily sick than a person who has two kidneys.

Need an extra kidney

Sometimes our kidneys stop working. When this happens, our blood can not be cleaned and we can become very sick. The only way to stay alive is to connect to a big machine that cleans your blood for you or undergo a kidney transplant.

It happened when my kidneys stopped working properly. My father gave me one of his kidneys. Thank you dad.

Two people are involved in a kidney transplant: a donor who will give their kidney and a recipient who will receive the kidney.

Once the new kidney has been introduced into the recipient, the donor and recipient have only one kidney that is functioning properly. The donor and recipient can live a long and happy life with only one kidney. They simply need to take extra precautions to eat healthily and exercise to stay in shape. A person living in Australia has been using a kidney graft for 45 years!

So while your body is working better when all your organs are inside you and are functioning properly, scientists still do not know exactly why we have two kidneys. However, it is good to know that we have some spare parts without which we can not live.

And if you are an adult reading this, it is good to make sure that you are registered as an organ donor and that you can also chat with your family so that she knows you want to make a Don. You can one day save a life.

Read more:
Curious Kids: Why are burps so strong?

Hello curious children! Do you have a question that you would like an expert to answer? Ask an adult to send your question to [email protected]

Please tell us your name, your age and the city in which you live. We will not be able to answer all the questions but we will do our best.