Precipitin reaction
Ok little one, have you ever seen a detective show where they use a magnifying glass to find clues? Well, scientists use something like that to find out which animals or humans might have left something behind, like blood or saliva.
This magnifying glass is not like a regular one, it's called a microscope. It can see things that we can't see with our eyes. This way, scientists can zoom in and see the tiny particles that are left behind, and they can figure out what kind of animal or human the particles came from.
Now, sometimes scientists want to see if a sample they found came from an animal or a human. To do this, they use something called a precipitin reaction. This is like a test that helps them figure out which animal or human the sample comes from.
The test works like this. Scientists take two things: the sample they found, and something that's called an antibody. Now, an antibody is like a key that fits only one lock. It's made to recognize just one kind of animal or human.
So, if the sample comes from a dog, the antibody that fits the lock of dog's blood or saliva is added to the sample. If the sample comes from a human, the antibody that fits the lock of human's blood or saliva is added to the sample.
When the right antibody is added to the sample, something happens if the sample is from the animal or human that the antibody was made for. A cloudy, or white reaction, called a precipitin reaction, appears. This tells the scientist that the animal or human that the sample came from was a match for the antibody.
Pretty neat, huh? Now you know how scientists figure out which animals or humans left something behind!
This magnifying glass is not like a regular one, it's called a microscope. It can see things that we can't see with our eyes. This way, scientists can zoom in and see the tiny particles that are left behind, and they can figure out what kind of animal or human the particles came from.
Now, sometimes scientists want to see if a sample they found came from an animal or a human. To do this, they use something called a precipitin reaction. This is like a test that helps them figure out which animal or human the sample comes from.
The test works like this. Scientists take two things: the sample they found, and something that's called an antibody. Now, an antibody is like a key that fits only one lock. It's made to recognize just one kind of animal or human.
So, if the sample comes from a dog, the antibody that fits the lock of dog's blood or saliva is added to the sample. If the sample comes from a human, the antibody that fits the lock of human's blood or saliva is added to the sample.
When the right antibody is added to the sample, something happens if the sample is from the animal or human that the antibody was made for. A cloudy, or white reaction, called a precipitin reaction, appears. This tells the scientist that the animal or human that the sample came from was a match for the antibody.
Pretty neat, huh? Now you know how scientists figure out which animals or humans left something behind!