"A comparison of soils (e.g. garden/ school / park / woodland) linked to controlling environmental factors".
Kirby Kruger I.B Higher Biology Group lab test "A comparison of soils (e.g. garden/ school / park / woodland) linked to controlling environmental factors". Planning (a) Introduction and background information Soil is an abiotic factor when considered as a natural surrounding. Different soil types affects individual species of plants and animals. A good example of how soil type affects plant life is to compare two different ecosystems with different soil compositions. The desert plains in central Australia consist of mostly sandy soil. The sand does not retain water well and is very dry and arid, but the plants have adapted so that their life cycles are completed in the 30 days that follow a good rainfall. Only some succulent plants which retain water very well manage to survive throughout the whole year. A comparison may be a peat bog; cold, waterlogged and deficient in nutrients, mosses and plants which obtain minerals through "alternative" methods (carnivorism) thrive here. Soil supports the basis of the Earth's ecosystems, and the agriculture and economy of the world. The three main types of soil include: * Sandy soils, which are light, heat up quickly and retain water poorly. Particles are relatively large with relatively big airspaces. A sample with more than 90% sand particles is just called "sand". * Clay soils and silty soils, which tend to be cold,
"An experiment to investigate how a factor affects the rate of photosynthesis"
BIOLOGY COURSEWORK YEAR 11 BY ABHINAV SARASWAT TITLE: "AN EXPERIMENT TO INVESTIGATE HOW A FACTOR AFFECTS THE RATE OF PHOTOSYNTHESIS" PLANNING EXPERIMENTAL PROCEDURES Photosynthesis is a process in which plants make their own food. Photosynthesis uses carbon dioxide, water light and chlorophyll to produce glucose and oxygen. They do this by taking in the carbon dioxide (CO2) from the air around it. The plant also needs water (H2O) and light (either from the sun or from other sources such as a light bulb). Most of the plants food is made in the palisade cell, which is in the leaf of a plant. Leaves are perfect for photosynthesis because they are flat and thin providing a large surface area for the absorption of light and gases. Photosynthesis happens in the leaf because there are a large number of chloroplasts there, each chloroplast contains the green pigment chlorophyll that gives the leaf its green colour and also captures light energy for use in the process of photosynthesis. In photosynthesis the light absorbed by chlorophyll powers the reaction that converts water and carbon dioxide into glucose and oxygen. Both animals and plants for respiration use oxygen produced by photosynthesis. The word equation for photosynthesis is: Carbon dioxide + Water Glucose + Oxygen The balanced chemical equation for photosynthesis is: 6CO2 + 6H2O
I want to find out if the concentration of the Hydrogen Peroxide affects the speed at which the potato gives off gas.
Catalase Investigation Aim: * I want to find out if the concentration of the Hydrogen Peroxide affects the speed at which the potato gives off gas. Planning Enzymes like catalase are protein molecules that are found in living cells. They are used to speed up reactions within the cell, and so are biological catalysts. Catalysts speed up reactions but they are not changed during the reaction. Enzymes only work on one specific type of substrate that means that there is only one kind of substrate that will fit into the enzyme's active site. Most enzymes optimum working temperature is 37°C (body temperature). Catalase is found in food such as potato that I will be using in my experiment. They are all very specific as each enzyme is used for different jobs. Catalase is used for removing Hydrogen Peroxide from the cells. Catalase is used to speed up the decomposition of the Hydrogen peroxide into water and oxygen. Preliminary experiment First of all I did a preliminary experiment, when we picked 15 potato chips at random and cut them down to the same length using a razor blade, making them even. I then set up the equipment as shown below and injected the hydrogen peroxide solution, and timed how long it took for 1ml of gas to be displaced as the H2O2 is attacked by the enzymes in the potato. ? Fig 1. Equipment setup To do this I will use the following: * * Potato
In this investigation I intend to explore the one of the factors that affects the rate of reactions. My research from textbooks and the Internet suggests that this depends on several factors; temperature, pressure, pH and concentration.
In this investigation I intend to explore the one of the factors that affects the rate of reactions. My research from textbooks and the Internet suggests that this depends on several factors; temperature, pressure, pH and concentration. After research and careful consideration, in my experiment I am going to investigate how a change in temperature could affect the rate of reaction. Using the enzyme in potatoes (peroxidase) reacting with hydrogen peroxide. Rate of reaction increases by: * An increase in temperature * An increase in concentration * An increase in surface area * A catalyst increases the rate but doesn't take part in the reaction The collision theory is when particles of substances collide with each other and there is a reaction. The higher the temperature the more energy the particles have for a faster reaction, more likely that the enzymes/substrates with collide an lock. An increase in temperature increases reactions rates because there is more heat energy in the particles therefore the collisions happens faster. Enzymes work slower at low temperatures because the movement of particles is slower. Molecules have less energy to collide; enzymes and substrates don't find each other and lock. Each enzyme works most effectively at a certain temperature called the optimum temperature. Which is around 50?C, but over this temperature the enzyme rapidly
investigate the effect of carbon dioxide concentration on the rate of photosynthesis.
7/07/2004 Bilawal Ajmal Khan 10A H/W/K Science Investigation Aim: to investigate the effect of carbon dioxide concentration on the rate of photosynthesis. Scientific knowledge: The Elodea (Canadian pondweed) makes bubbles of oxygen when it photosynthesises. The faster it photosynthesises the faster it makes oxygen. The plant uses dissolved carbon dioxide. This can be made by adding hydrogen carbonate solution to the water. The factors which can effect how quickly a plant can make food by photosynthesis include the following. * Carbon dioxide concentration - this can be simulated by changing the volume of hydrogen carbonate solution added to the water. At low concentrations of carbon dioxide the rate of photosynthesis is very slow. As you increase the concentration of carbon dioxide the plant can make food faster and faster. There is a limit however. There comes a time when adding more carbon dioxide does not increase the rate of photosynthesis. The plant is making food as fast as it can under the conditions. * Light intensity - this can be altered by either changing the brightness of the bulb or by moving the bulb further and further away from the plant. Plants need light energy in order to make food. The more light they have the faster they can make food.
Investigating the enzyme 'Catalase'
Year 11 Coursework: Investigating the enzyme 'Catalase' AIM To look at Hydrogen Peroxide (H2O2) being broken down into H2O and Oxygen (O2). We will also investigate the factors that change the rate of reaction. MATERIALS Scalpel White tile 30cm clear plastic ruler Test tubes & rack Stopclock 0ml measuring cylinder 2ml pipette H2O2 Cylinder of potato Goggles Cloth SAFETY The hydrogen peroxide is toxic, and is a bleaching agent therefore if it is spilled it must be cleaned up straight away. You must wear safety goggles to protect your eyes. The scalpel is dangerous, it is very sharp so you must not run and also be very careful while handling a scalpel. METHOD (pilot experiment) ) We will measure out the desired amount of H2O2 and pour it into a test tube 2) We mark and cut out the desired amount of potato with a scalpel. 3) Every 4 minutes we will measure the height of froth produced, to 1 decimal point, from the meniscus. 4) Record results 5) Plot a graph of results We will carry out a pilot experiment to find the best lengths of potato to use for the real experiment. FAIR TESTING To make this a fair test I will: * Monitor the room temperature * Use the same volume of H2O2 & same pH * Same batch/age/brand and freshness of potato * Same diameter of potato * Same ruler * Same person measuring each time, from the same level RATE OF REACTION If we
The Importance of Water in Living Organisms
Matthew Bradfield The Importance of Water in Living Organisms Water has importance inside cells and externally. This may be because it has interesting chemical and physical properties; it can be found naturally in all three of its states. However its molecules are bonded together by hydrogen bonds, this brings up its melting and boiling points, i.e. its boiling point would be -120¢ªC rather than 100¢ªC. Also because it contains slightly negatively charged oxygen atoms and slightly positively charged hydrogen atoms making it polar. Water has been called a universal solvent because of it polarity. This means it can easily ionise substances, many compounds, whether ionic, polar or covalent will dissolve in it, therefore more reactions take place while in solution with water. Often in organisms substances must be in solution and water is the solvent. Plants can only obtain mineral salts in solution and human digestion will only dissolve soluble foods, meaning large starch molecules must be broken down into soluble sugars. Also many organisms living in water spend most of their time underwater, yet they require oxygen to respire, and as water is such a good solvent the required oxygen gas is dissolved in the water. Water is the most abundant component in any organism, the lowest is 20% in seeds, while jellyfish are 99% (hence the transparency). It plays vital roles in
To determine the water potential of a potato tuber cell using varying salt solution.
Aim To determine the water potential of a potato tuber cell using varying salt solution. Introduction Osmosis is the diffusion of water molecules from a region where it has higher water potential to a region where it has lower water potential through a partially permeable membrane1. As osmosis is a type of diffusion the same things that affect diffusion have an effect on osmosis some of theses things are: * The concentration gradient - the more the difference in molecules on one side of the membrane compared to the other, the greater the number of molecules passing through the membrane and therefore the faster the rate of diffusion2. * The surface area - the larger the area the quicker the rate of diffusion * The size of the diffusing particles - the smaller the particle the quicker the rate and polar molecules diffuse faster than non-polar ones3. * The temperature - the higher the temperature the more kinetic energy the particles have and so the faster they move. From the diagram4 we can see the process of osmosis in a simple expression. On the right side there is pure water, which has the maximum water potential of 0. Water potential is the pressure created by water. As you can see from the diagram the pure water is pushing its way through the semi permeable membrane at a high pressure. This is its water potential. Water potential is measured in kilopascals (kPa)
The aim of this experiment is to investigate the movement of water into and out of plant cells by osmosis. The cells chosen for study will be taken from potato tubers as they provide a ready supply of uniform material.
Aim The aim of this experiment is to investigate the movement of water into and out of plant cells by osmosis. The cells chosen for study will be taken from potato tubers as they provide a ready supply of uniform material. Background Information Any substance dissolved in water is called a solute; a solvent is a liquid that is able to dissolve another substance, (a solute), to form a solution. The water content of plants varies depending on environmental conditions. In land plants it plays a vital role in structural support and mineral transport and thus a lack of water may lead to wilting or possibly death. Water is mainly absorbed through the roots, which are covered in specially adapted root hair cells, with large surface areas and thin cell walls to aid absorption by osmosis. The evaporation of water through stomata on plant leaves causes a transpiration stream, causing the water to be drawn up through xylem vessels. Osmosis is the flow of water molecules by diffusion through a partially permeable membrane from areas of high water potential (low solute concentrations) to regions of low water potential (high solute concentrations). All plant cell membranes are partially permeable, which means they allow some substances to penetrate them but not others. Whether water enters the cell by osmosis will depend on the balance between external and internal solute and water
The Effects Of Changing Light levels on the Rate of Photosynthesis
The Effects Of Changing Light levels on the Rate of Photosynthesis Aim: To investigate a factor that affects the rate of photosynthesis. Outline: A piece of pond weed will be cut and placed into a beaker containing water and sodium hydrogen carbonate. A lamp will be shined on to the pond weed and the amount of bubbles released from the plant will be counted. The lamp will be adjusted to different distances from the plant to try and obtain different results. Photosynthesis Equation: 6CO2 + 6H2O light energy & chlorophyll C6H12O6 + 6O2 Variables: Experimental Variable- Light intensity is to be the variable explored in this investigation. Light intensity can be changed by increasing or decreasing the distance from the light source to the plant. Fixed Variables- Carbon Dioxide- CO2 concentration can affect the rate of photosynthesis since the more CO2 in the air, the more CO2 that can diffuse into the leaf. This variable can be fixed by adding a fixed amount of sodium hydrogen carbonate to the beaker and plant. Water- Water is required in the photosynthetic reaction. When plants lack water, their stomata close to prevent further water loss. At the same time, closing the stomata cells doesn't allow CO2 to diffuse into the leaf. Water is also linked to the carbon dioxide factor. Water can be kept a constant by keeping the same amount of water in the beaker. Temperature-
