Biology Experiment: Osmosis

On Monday 11th April, we changed science classes to biology and agricultural science with Ms Gorman. Our first experiment with her was to show osmosis across a semi permeable membrane. Osmosis is the movement of water across a semi permeable membrane from a level of high water concentration to a level of low water concentration. The experiment used visking tube which like a thin plastic tube that only allows water through. We also had beakers, concentrate sucrose solution, deionised water and an electric balance. We had to cut the tubing the same length and put it under the water to soften it. It was difficult to open the tube as it was so thin plastic! We then half filled one of the tubes  with the deionised water and the other with the sucrose solution. After that, we tied and weighed them and placed them in beakers full of water so that the tube was fully submerged. After the experiment, we left it for a few days for he reaction to happen. Mr Kelly also set up an experiment where he put eggs in beakers of vinegar. he left them for a few days, by which time the egg shell had dissolved. He put salt water in the beaker and this absorbed all the content in the egg. After that, he added coloured water and the egg absorbed the water. After we had come back to the osmosis experiment, the tube with the sucrose solution had a higher mass as it has absorbed more water and the deionised water had stayed the same mass. 

Science Experiments in the Gaelscoil

On Monday the 14th  March, we went to the Gaelscoil in Ballyshannon to show science experiments to the senior classroom. My group was made up of me, Caroline, Róisín, Eva and Emma. We did the food colouring in milk experiment first to show how the food colouring separated when the soap was added because of the fat in the milk. We then did an experiment to show how if you added water to a balloon and lit a candle undeerneath it, the balloon would not pop. We had to prepare for the experiments a few weeks in advance so that we knew the reason behind the experiments and so that we had a work sheet to give to the children. We also had to ask them a science question. We asked how many planets are in the solar system ( including Pluto) and to name them. The day was great fun and all the children seemed to enjoy it, especially the Van Der Graaf generator! 

Physics experiment

At the moment in Physics, we are talking about the speed of sound in air and, on Monday 11th January, we did an experiment to prove the speed of sound in air is around 340m/s. The experiment meant that we had to use a graduated cylinder part- filled with water and with a resonance tube and tuning forks, find 1/4 of the wavelength of sound. We hit each tuning fork off a block of wood, then placing it above the graduated cylinder, we moved the tuning fork up and down until it gave the loudest noise. We then recorded this height from the top of the water. We then had to multiply using the formula; λ= 4(l+0.3d). After we had found the length of the wavelength, we then had to find the speed of the wavelength using the formula; c=fa. It was an interesting experiment and although our result average was 402m/s we still found how to prove the speed of sound.

Circuit experiment

This is similar to our experiment

For World Science we have begun to study Physics with Mr McPhelim and have started to do circuits. The experiment we did last week was to create a basic circuit and to measure the resistance of a copper coil as you increase the voltage output. We had to record our results and place them on a straight line graph. In the experiment we had to measure the current we were placing through the coil using an ammeter as well as measuring the resistance of the coil using and ohmmeter. We used a variable resistor to change the current going through the coil and by measuring the resistance after it had gone through the coil, we could measure the resistance of the coil- r=v/a

The Heart

On Monday 5th October, TY4 dissected lambs hearts as part of our study of the circulatory system. I was paired with Roisin Maguire and she used the scalpel to cut into both sides of the heart. We looked at the different chambers of the heart as well as the veins and arteries like the aorta and the pulmonary vein. It was interesting to look at an actual heart instead of just diagrams and gave me a better insight into what the heart looked like. We also had to do a poem, song or rap including all the different parts of the heart. My team’s poem was:

Through the vena the blood flows,

Into the right atrium you know.

The right ventricle are next hand in hand,

The gases exchange in the lungs so it can.

So from the lungs to the pulmonary vein in a beat,

To the left atrium and ventricle in a leap,

The aorta is last but not least.