A few classes ago in science we did a strawberry DNA extraction lab which was really fun because we haven’t done a lab in a while. We started off by coming up with a hypothesis for the lab about what we thought would happen and how to extract the DNA from the strawberry. In our hypothesis we started by saying we would use the materials including the ethanol, soap and salt to extract the DNA from the strawberry.
This is the sheet we filled out for the lab:
Our next step was to take the materials including 1 strawberry, 5ml of dish soap, 2.5ml salt, and 25ml water and crush them in a plastic bag until smooth. We then put the liquid into a test tube and added 10ml of ice cold ethanol. The reason we crush up the strawberry is to break down the plant cell wall of the strawberry which allows the ethanol to reach the DNA in the nucleus. When the DNA was taken out of the strawberry it formed a white string like thing between the alcohol and the strawberry solution. It was very interesting to watch. We then used a paperclip to pull out the DNA and observed it under a microscope.
Here is a photo:
Here is a video of the whole process:
This was a fun project to do. Another interesting thing we have done recently in science class was learn about genes and DNA. We did this by making a chart that had six different traits that would define our characteristics and the genes that have been passed down to us. We had six categories of traits to look at including earlobes attached or not attached, hairline widow’s peak or straight hairline, thumb hitchhiking or straight, ability to curl your tongue or not curl your tongue, dimples or no dimples and finally having hair on the middle joint of your fingers or the absence of hair on the middle joint of your fingers. After writing all these categories down, we then asked different people in the class if they had that certain characteristic or not. In the end of this activity we found the most common and least common categories. Some of the least common traits included not being able to curl your tongue and having a widows peak.
After this activity, we split off into groups and made a model to represent the DNA. We also learned about the two base pairs on the DNA including AT and CG which always pair with each other. My group’s DNA model turned out ok but it wasn’t very pretty. However it helped us learn about DNA in a different way than just reading out of the textbook.
Here is our model:
Overall, these past few classes have been interesting and fun where we learnt about DNA and genes as well as having a revision of the cell.