The effect of osmosis in potato cells with different concentrations of

The effect of osmosis in potato cells with different concentrations of sucrose solution Aim: To test the effect of different concentrations of sucrose solution to osmosis in a potato cells by putting potato pieces in test tubes of water containing different concentrations of sucrose solution. Scientific Theory: Osmosis is defined as the movement of water molecules across a partially permeable membrane from a region of high water concentration to a region of low water concentration. In a high concentration of water the amount of solute (e.g. sugar) is low. This could be called a weak or dilute solution. In a low concentration of water the amount of solute (e.g. sucrose) is high. This could be called a strong or concentrated solution. When two such solutions are divided by a partially permeable membrane the water will move from the area of high concentration to the area of low concentration, until both sides are equal (have reached equilibrium). Knowing that osmosis will occur across a partially permeable membrane whenever there is a difference between the water concentrations on the two sides of the membrane, and knowing that when this happens to cells they will either become turgid if water flows into them, or flaccid if water flows out of them, and thus change their volume, we want to test the hypothesis that: If the concentration of a solution into which a cylinder of potato is placed is greater than a certain level the cylinder will contract, and if the concentration is less than that level it will expand. The cell membrane in cells is partially permeable and the vacuole contains a sugar/salt solution. So when a cell is placed in distilled water (high water concentration) water will move across the partially permeable membrane into the cell (lower water concentration) by osmosis, making the cell swell. This cell is now referred to as turgid. If done with potato cells the cells would increase in volume and mass because of the extra water. If these potato cells were placed in a solution with a low water concentration, then the opposite would happen. Water would move out of the cell into the solution. In extreme cases the cell membrane breaks away from the cell wall and the cell is referred to as flaccid. The potato cells will have decreased in volume and mass. The greater the concentration of water in the so... ... for example, with a carrot or an apple to see if osmosis affects them in the same way as it does potato. I would also widen the range of sugar concentrations to include 1.1M 2M. Moreover, I would like to see if and when the cells reach a maximum and minimum weight. Temperature could also be changed, for example the samples could be placed in different test tubes at different temperatures to see if temperature played its part in the osmosis of potatoes. 5 sets of 3 potatoes could be placed in test tubes at 10oC, 20oC, 30oC, 50oC and 60oC. Then leave them for 24 hours making sure all the variables in the first experiment still apply however just using one molar solution. Then after 24 hours re-weigh the samples and record the result. I would expect that at high temperatures the potato samples would gain the most weight. This is because at high temperatures the water molecules would move faster and therefore equal the concentration faster. A preliminary experiment could be set up beforehand to find out how long the experiment should be kept going because if the concentration of the potatoes equalises then the weight of the potatoes will be almost exactly the same.

Disabled by Wilfred Owen Essay

When you hear ‘death’ you think of pain and suffering. The poem Disabled by Wilfred Owen shows that he regrets some major decisions he made in his very short life; such as going to war. Throughout the poem he states how much he regret going to war. He used lots of terms to describe his pain and suffering in the war and also after coming home from the war. How he is against all wars. He informs young men on how the war really is. Another source I looked at was the movie Gallipoli. The protagonist was so eager to go to war. He was so excited thinking it was going to be fun and above all he was out into the light horse category. He was constantly saying that he wanted to get home and share his experiences with his family, only little did he know that is was the last time he was going to see them. Good afternoon fellow students and Ms Dadd/Fegatilli. We have all been studying war stories for a week or two. The 2 forms of writing we have been studying are Disabled by Wilfred Owen and some of us have been studying the movie Gallipoli. The protagonist in â€Å"Disabled† speaks about how he misses all of the wonderful memories that he had only last year, before he lied his way to go to war underage to show off, only to lose limbs and become an old man who is only about 19 and has aged as though until he looks and feels elderly. He has lived in an institute for most of his life after he came back from the war. This teaches us that you must cherish what you have and not to show of how good you can be. You never know when you suddenly lose important things to you because of the decisions you have made before. Wilfred Owen uses repetition throughout the poem to try and bring these messages of regret across, such as â€Å"Now he will never feel again† and â€Å"Now, he is old; his back will never brace;† to emphasis what he will never have again and how much he has lost. Wilfred Owen sets the mood to match the theme. The theme of this poem is a look at what has become of a man who made wrong choices in life then to later regret it. In Disabled, he has used emotive language and powerful words to emphasize the theme. The second source I looked at was the movies Gallipoli. The protagonist is so keen of the idea to go to war, that he doesn’t think of how it will affect others and how it will affect himself. So he signs the form; which proudly states his is over 21. The film Gallipoli shows that men back in those days didn’t take it seriously. They thought it was all fun and games right until they were in the trenches about to shoot people or possibly even go over when they were commanded to. So as you can see, not many people made it out alive. They thought it was going to be all fun and games but they were very mistaken. So throughout this speech I have mentioned the effects that both protagonists have to deal with. Death brings pain and suffering but in this case it was the war. Thank you for listening to my speech.

Polonium Facts - Element 84 or Po

Polonium (Po or Element 84) is one of the radioactive elements discovered by Marie and Pierre Curie. This rare element has no stable isotopes. Its found in uranium ores and cigarette smoke and also occurs as a decay product of heavier elements. Although there arent many applications for the element, it is used to generate heat from radioactive decay for space probes. The element is used as a neutron and alpha source and in anti-static devices. Polonium has also been used as a poison to commit assassinations. Although the position of element 84 on the periodic table would lead to categorization as a metalloid, its properties are those of a true metal. PoloniumBasic Facts Symbol: Po Atomic Number: 84 Discovery: Curie 1898 Atomic weight: [208.9824] Electron configuration: [Xe] 4f14 5d10 6s2 6p4 Classification: semi-metal Ground level: 3P2 Polonium Physical Data Ionization potential: 8.414 ev Physical form: Silvery metal Melting point: 254Â °C Boiling point: 962Â °C Density: 9.20 g/cm3 Valence: 2, 4 References: Los Alamos National Laboratory (2001), Crescent Chemical Company (2001), Langes Handbook of Chemistry (1952), CRC (2006)