Every living thing is unique—no two things are exactly alike (except for identical twins). We know this is true because of deoxyribonucleic acid. That’s a HUGE word, so don’t worry about using it. You can call it DNA like all scientists and medical professionals do.
DNA molecules look like a twisted ladder and are made from our genes. DNA decides what we look like if we will have diseases or handicaps, and many other things about why we act and look the way we do.
How do we get our DNA?
Our DNA comes from our parents. They get their DNA from their parents (our grandparents) and they get theirs from…
This is why people in the same family look like their parents, siblings, grandparents, cousins, or other family members.
DNA is also the reason people groups look similar. In other words, DNA is why people from China look different from people in Mexico and people in China and Mexico don’t look like people from Greece.
What does DNA look like
Doctors and scientists can look at a person’s DNA by looking at a person’s hair or skin cells under a microscope. They can even see a person’s DNA in their spit.
Since you aren’t a doctor or scientist and since you don’t have a microscope that is powerful enough to see DNA inside the cells of the hair, skin, or spits, let’s take a look at DNA that we can see.
Let’s look at the DNA inside spinach.
Here is what you need:
- ½ cup fresh spinach,
- Rubbing alcohol
- 2 T dish soap
- About 1/8 teaspoon of meat tenderizer
- ¼ teaspoon salt
- Clear glass measuring cup
Here is what you do:
- Blend the water, spinach, and salt in the blender until soupy.
- Carefully pour the mixture through the strainer into the clear glass measuring cup
- Add the dish soap and set the timer for 10 minutes
- When ten minutes have elapsed add the meat tenderizer; stirring slowly and carefully Observe how much liquid is in the measuring cup and carefully add an EQUAL amount of rubbing alcohol. Example: if you have ½ cup liquid add ½ cup rubbing alcohol
- Set the timer for 3 minutes
- When the time has elapsed, look to see what has happened
Here is what is going to happen:
Crushing the spinach broke down the cell structure of the spinach so that its DNA is exposed. The dish soap pulls the DNA out of the cells like it pulls grease off of dishes. The rubbing alcohol mixes with the soap to show the threads of DNA.
Repeat this experiment using any of the following flowers and vegetables:
- Beet tops
- Rose leaves
Were you able to ‘pull’ the DNA from them? What were some of the differences?