We are studying the structure of DNA.
DNA extraction from strawberry.
Materials needed: Zip lock bag, two strawberries, 30 ml water, teaspoon dishwashing liquid (detergent), 2 ml salt, sieve
Step 1: Place strawberry in zip lock and squish.
Step 2: Mix salt, water and detergent. Add to zip lock. Mix with strawberry mush.
The detergent dissolves the phospholipid layers of the membranes. The salt makes the DNA less hydrophilic.
Step 3: Filter the liquid into the glass beaker using the sieve.
Add approximately 2 cm cold methylated spirits slowly on top of the strawberry extract.
Use toothpicks to twirl the DNA out of the methylated spirits.
Building a DNA model
The passive movement of molecules or particles along a concentration gradient, or from regions of higher to regions of lower concentration.
It took approximately 1 hour for the colours in the beakers 1, 3 and 5 to diffuse into beakers 2 and 4. The Red and yellow turning orange and the yellow and blue turning green.
The diffusion of the colour pigments on smarties in water takes about 1 minute
08:00 Monday morning 9 May 2016 we covered a branch of a tree still covered in leaves with a zip lock bag and tied it off with an elastic band.
After 2 hours water vapour was clearly visible on the sides of the plastic bag.
We decided to leave the bag on for 24 hours to determine the volume of water that had been released.
From left to right
- Ntwayabokona, Maumakwe, Abdul Gafar, de Vos, Ditibane, Morebodi, Ledula
- Kaker, Mothoagae, Carrim, Louw, Sesoai, Mahapela
- Voyi, Modise, Radebe, Crater, Molekane, Scheepers, Ochieng
More than 250 projects were presented at schools in the region this year of which educators had to choose the best to enter the Area expos. The Klerksorp expo took place on 30 July at Klerksdorp Library and the Potchefstroom expo at Laerskool Mooirivier on 23 July. The best 120 projects were selected to participate in the Regional expo. We (Potch Boys High) entered 10 projects (20 learners) and all the projects were selected for the Regionals.
The Regional expo was held on 25 August at the Banquet Hall in Potchefstroom. We were very successful here.
P Mahapela received bronze for his project The effect of various chemicals on seed germination’,
O Motoagae and L Ntwayabokone received bronze fro their project ‘Skyscrapers’
Silver medals were awarded to
- F Abdul-Gafar and S Radebe ‘Organic Life support’
- L Seeletse and M Zuze ‘ Different water solutions and plant growth’
- T Ledula and O Ochieng ‘Wireless electricity’
- U Carrim and M Voyi ‘Effect of cellphone radiotion on plant growth’
F Abdul-Gafar and S Radebe were selected as part of a team of 22 projects from the NortWest Province to participate at Nationals hosted at Birchwood hotel in Boksburg, held from 6 to 8 October 2011. They competed against 200 projects from all over the country fro various prizes and bursaries. The boys worked hard to improve on their project and were duly awarded a silver medal. We all look forward to the 2012 event.