Ok kiddo, have you ever heard of genetically modified organisms or GMOs? No? Well, In science, people can change the genes of plants and animals to make them grow faster or bigger or taste better. But sometimes, these changes can hurt the environment or other living things.
Now, some countries agreed to make rules about changing the genes of plants and animals so that they don't hurt the environment and people too much. That's what the Cartagena Protocol on Biosafety is all about.
It's like a big agreement between countries to protect the environment from any harm that people could cause when they are changing the genes of things.
Just like how you and your friend make rules like, "we can play with blocks, but when we are done, we have to put them back in the box." Each country that agreed to this protocol has to follow these rules too so that nobody gets hurt.
The rules say that if someone wants to bring a genetically modified plant or animal to a new country, they have to make sure it won’t hurt the environment or people there. They have to tell the other country what they want to bring, how they made it, and what they think will happen if they release it into the wild.
The other country can say yes or no, but they have to be careful to make sure that the environment won't be hurt.
So basically, the Cartagena Protocol on Biosafety is a set of rules to make sure that when people change the genes of plants and animals, they don't hurt the environment around them.