Osmosis - how does the concentration of water affect the mass of a potato?
Biology Coursework Osmosis- how does the concentration of water affect the mass of a potato? Abubakar Hatimy Aim: - My aim is to find the percentage change of mass when a small piece of potato is placed in to molar sucrose solution Apparatus: o Molar sucrose solution 0.0 - 0.5 o Potato o Cutting board o Knife o Weighing machine o Glass test tube o Glass test tube holder Plan: - My plan is too find the percentage change of mass of a small piece of potato when placed in to molar sucrose solution by using osmosis. Osmosis is explained below Osmosis Osmosis is the passage of water molecules from a region of their high concentration to a region of their low concentration through a partially permeable membrane. It is best regarded as a form of diffusion in which only water molecules move. For example look at Figure 2. The solute molecules are too large to pass through the pores in the membrane, so the movement of water molecules can only achieve equilibrium. Solution A has the higher concentration of water; so there will be a net movement of water from A to B by osmosis. At equilibrium there will be no further net movement of water. The tendency of water molecules to move from one place to another is measured as the water potential, represented by the symbol
To investigate the effect of varying concentration of glucose solutions on the osmotic activity between the solution and potato slices.
INVESTIGATING OSMOSIS IN PLANT CELLS AIM: To investigate the effect of varying concentration of glucose solutions on the osmotic activity between the solution and potato slices. SCIENTIFIC THEORY: Osmosis is defined as the net movement of water molecules from a region of high concentration to a region of low concentration of water, through a partially permeable membrane, which only lets smaller molecules through. This can also be described as movement down the concentration gradient. The molecules continue to diffuse through the membrane until both sides reach a state of equilibrium. This is also known as the isotonic point when the molecules are equally distributed on both sides of the membrane so that no one area has a higher or lower concentration than the other. Plant cells have a strong cell wall and a partially permeable cell membrane around them. When cells are surrounded by a solution more dilute than their own, (hypotonic solution-with more water than solute molecules), the cell swells up and becomes "turgid". This is because the water molecules diffuse from the solution to the plant to equal out the concentration levels. The strong cell wall prevents them from bursting. Figure 1- A turgid plant cells in more dilute surroundings (from "Biological Sciences Review") When they are surrounded by a solution more concentrated than their own, (hypertonic- less
Investigation to see what effect different concentrations of solution has on osmosis
INVESTIGATION TO SEE WHAT EFFECT DIFFERENT CONCENTRATIONS OF SOLUTION HAS ON OSMOSIS Osmosis is the movement of water molecules across a partially permeable membrane from a region of high water concentration to a region of low water concentration. Aim The aim of the experiment is to investigate what effect different concentrations of solution has on osmosis. Prediction I think that in a more concentrated solution of molar, the potatoe chip will lose more weight, than in a solution less concentrated. In pure water, the potatoes will swell due to water entering their cells by osmosis. However, in rich sugar solution i.e 1 Molar, the potatoe chip will shrink as water is leaving thwe cells by osmosis. Test tube 1, will be for sugar solution, test tube 2 for 0.5 Molar and test tube 3 for pure water solution i.e 0.0 Molar. Apparatus * Test tubes (x3) * Measuring Cylinder * A stop watch * Sieve * Potatoe chips * Weighing scale * Ruler * Knife Fair Test For the results to be the most accurate and reliable they can, I will repeat the experiment four times. For the investigation to be a fair test, the following should and will be considered: * The pieces of potato must be the same width and length, as they must have the same surface area given to the solutions. This means that if one cylinder is given more solution than another cylinder, then the one with the larger
To Investigate the Effect of Light Intensity on The Rate of Photosynthesis
To Investigate the Effect of Light Intensity on The Rate of Photosynthesis Predication As it is seen in figure 1 that in order for any plant to photosynthesis it need three main raw materials: . Water 2. Carbon Dioxide 3. Light These are also known as 'limiting factors' of photosynthesis (another limiting factor that has not been mentioned above is temperature), therefore if the limiting factors are increased the rate of photosynthesis should also increase. Carbon Dioxide + Water Sugar + oxygen Sunlight Figure 1. Formula for Photosynthesis From figure 1 the fact that without light photosynthesis could not happen could also be concluded. This is proven from a previous experiment, which is set up to compare if light is limited would the plant still produce glucose as food. This is done by setting up a plant that had been given all the raw materials to photosynthesis, compared to a plant that had light limited. As the result of this experiment, when iodine solution, which is used to test for glucose, is added to the decolourised plant, which had all the right raw material to photosynthesis, it turned blue-black which mean glucose had been produced. And when iodine solution is added to the decolourised plant with light limited it stayed reddish brown, which showed that glucose had not been produced as. From here a prediction could be made that if the light
To experiment with different variables that effect photosynthesis using a computer simulation, and take measurements accordingly.
Photosynthesis - Science Coursework: Task: To experiment with different variables that effect photosynthesis using a computer simulation, and take measurements accordingly. Prediction: I predict that firstly the increased temperature will generate more oxygen, however this will only apply to a certain degree, probably around 35?C to 40?C in my opinion, where I think the equation will be at its optimum heat capacity. And for the additional experiment, I think that an increased in Carbon dioxide levels will again produce greater amounts of Oxygen. Lastly, a higher light intensity, in my opinion will produce increased levels of Oxygen because as the formula states sunlight is essential for the reaction to take place, therefore it is likely the greater this is the more Oxygen is produced. Method: We first decided to find out how the temperature affects the rate of photosynthesis. Using the computer simulation, we tested from 0?C to 50?C, at 5?C intervals. All other variables were set at one certain measure. Take for instance Light Intensity, which was arbitrary at 50 throughout and NaHCO3, which was at 2%. We then let each individual test run for 10 minutes, and then taken the oxygen level produced, measured in mm. As a secondary experiment we tested for the effect of light intensity to the rate of photosynthesis. Again we fixed the amount of NaHCO3 to 2% and left the
How Does Exercise Effect The Body?
Amandeep Gill GCSE Coursework How Does Exercise Effect The Body? Aim : My aim is to find out how exercise effects the body, particularly looking how your heart rate changes from a stationary position to the after effects of the activity of my choice. The exercises I have chosen to carryout are sprinting, jogging, walking and performing star jumps. Word Equation Formula for Respiration, Glucose + Oxygen Carbon Dioxide + Water + Energy Symbol Equation Formula for Respiration, C6 H12 O6 + 6O2 6CO2 + 6H20 + Energy I will be using the formula for respiration in the latter stages of my experiment and showing how it is related to exercise? Equipment Used, The following is a list of the equipment I will be using for my practical experiment: Stop Clock - Used to time various stages of the experiment, e.g. 30 seconds for stationary pulse. Tape Measurer - Used to measure the twenty- five metre strip used in the majority of the exercises. Pen and Paper - Used to record the results whilst the activities are taking place. Pair of Trainers - Used instead of school shoes, as they can often be painful when running in and this could effect the pace in which the experiment is carried out at. Towel - Used after the practical experiment has taken place. Diagrams of the Equipment, Prediction, From previous scientific knowledge, I predict that when doing
How does Exercise affect the pulse rate
Nazneen Rajabali How does Exercise affect the pulse rate? What is the pulse? The pulse is felt by the beating of the heart or blood vessel. The pulse is specially felt when a finger is put on top of an artery. In an artery, the pulse is felt when the artery expands and contracts. The walls of the artery are made up of elastic walls. The contracting of the heart muscles forces blood into your arteries and because the walls of the arteries are elastic they can take this pressure. They expand and contract as the blood is pushed through and this is what is felt as your pulse. To feel your pulse you need to find a main artery in your body. The most common place to find a pulse is on your wrist or the side of your neck. The resting pulse of an average human is 70 beats per minute. However, during exercise the rate my increase to 200 beats per minute. Prediction I predict that by increasing the amount of exercise I do, my pulse rate will also increase. I have researched and used my scientific knowledge to predict this. I have researched how the body changes during exercise so I know that the more exercise I do my pulse rate will go up: How the body changes during exercise? The body changes during exercise. Firstly, the muscles start to work harder so respiration speeds up in muscle fibers to provide extra energy. When respiration takes place the waste product, carbon
Pigment Chromatography Lab
Pigment Chromatography Lab Sahar Rudgar Mr. Wright SBI4U- Per. 4 Tuesday Mar. 22nd, 2005 Purpose: Separation of plant cell pigments by paper chromatography. Materials: * Chromatography paper * Scissors * Test tube * Chromatography tube and solvent * Pencil * Fresh leaf Procedure: .) A test tube was obtained containing developing fluid (9 volumes of petroleum ether / 1 vol. acetone) and a stopper with a hook. 2.) A 15 centimeter strip of Whatman chromatography strip was cut. 3.) One end to a point was trimmed with scissors. A pencil line was drawn just above the point. 4.) The strip on a hard clean flat surface was laid. A fresh leaf was put over the paper and the tissue was crushed onto the pencil line by rolling the edge of a test tube along the leaf surface. The leaf was moved and this was repeated several times. The line of pigment which has been crushed onto the paper was kept as thin as possible. 5.) The paper was immediately hooked onto the hook of the tube stopper so that the tip of the paper was immersed in the developing fluid. The paper was hanging vertically and not touching the sides of the tube. 6.) The tube stood for about 10 minutes. The movement of the solvent front was observed. When the solvent front was within one centimeter of the hook the paper was removed and a pencil line was drawn at the edge of the front (This was done quickly
To investigate the effect of osmosis.
Osmosis Investigation Planning Experimental Procedures Aim To investigate the effect of osmosis. Background Research In order to attain a working knowledge of osmosis and its effects, I looked through school textbooks together with some information I had obtained at the library. Many substances pass in an out of cells by diffusion. Diffusion is the movement of particles from a region where they are at a higher concentration to a region where they are at a lower concentration. This process does not require energy from respiration. An example of this is the way cells take up oxygen and get rid of carbon dioxide: The greater the difference in concentration betIen the two regions, the faster the rate of diffusion. Small particles also diffuse faster than larger particles. Water passes in and out of cells by a type of diffusion, called osmosis. Osmosis is the diffusion of water in plants, from a dilute solution to a more concentrated solution, across a partially permeable membrane; or from a high concentration to a lower concentration. This is shown below: Put simply, osmosis is the passage of water across a partially permeable membrane from a dilute to a concentrated solution. When a substance, such as sugar, dissolves in water, the sugar molecules attract water molecules and combine with them. The water molecules now combined with sugar molecules are no longer free to
Investigating Osmosis Using Potato Cylinders
Investigating Osmosis Using Potato Cylinders Aim:- The aim of this investigation is to see how the sugar concentration of a solution eventually affects the size of a submerged potato cylinder. I am conducting this experiment to further my understanding of osmosis. The increase or decrease of the size of the potato cylinder can be explained by osmosis. ________________________________________________________________________ Introduction:- The core scientific principle, related to my investigation is that of Osmosis, below I intend to relay information thus. Osmosis:- Osmosis is basically a form of diffusion, but more specifically: it is the movement of water molecules from an area of high water concentration, through a partially permeable membrane to an area of lower water concentration. Partially permeable membrane:- A partially permeable membrane is a membrane, with holes so small that only water molecules are small enough to fit through, bigger molecule, for instance, sugar and salt are not small enough to fit through. In my experiment I will be testing Osmosis with a potato in relation to the solution that it is in, one solution will be pure water, the second will be a 5% glucose concentration, and then the next a 10% glucose concentration, and then a 15% glucose concentration. My hypothesis and the experiment will predominately affected by the type of