An Investigation on the Effect of Enzyme Concentration on rate of hydrogen peroxide breakdown.
An Investigation on the Effect of Enzyme Concentration on rate of hydrogen peroxide breakdown Planning Aim The aim of this investigation is to study how the rate of reaction i.e. rate of substrate breakdown. is affected by varying the concentration of the enzyme. The enzyme that is used in this investigation is catalase, which is sometimes referred to as peroxidase. The substrate is hydrogen peroxide. Celery extract is used in this investigation to provide the catalase, and a solution of hydrogen peroxide will have been prepared beforehand. Background Knowledge * Introduction Our liver has the vital function of detoxifying any poisons that may be absorbed with food or produced as a wasted product by the body itself. Hydrogen peroxide (H2O2) is one such example. This highly toxic chemical is a waste product of the deamination of amino acids in the liver. If the amount of hydrogen peroxide builds up to large amounts, the poisonous material can quickly kill cells. Therefore, the body needs a mechanism of breaking down harmful materials such as hydrogen peroxide. Hydrogen peroxide will breakdown to harmless products without the use of enzymes. However, the reaction is so slow that levels would rapidly increase which would result in death of that organism. One method of rapid detoxification is the use of enzymes, these act as catalysts which greatly increase the rate of
Outline the impact on the evolution of plants and animals of: Changes in physical conditions in the environment. Changes in chemical conditions in the environment. Competition for resources.
Blueprint of Life Summary > Evidence of evolution suggests that the mechanisms of inheritance, accompanied by selection, allow change over many generations: * Outline the impact on the evolution of plants and animals of: * Changes in physical conditions in the environment. * Changes in chemical conditions in the environment. * Competition for resources. Evolution theory: * All living species come from preexisting species and that all living things have a common ancestor in some initial form of primitive life. * Changes in the environment of living organisms can lead to the evolution of plant and animal species. * Changes in the environmental conditions may be physical, such as temperature changes, or chemical, such as changes in water salinity and also competition - for example, competition for resources such as food and water, or competition to reproduce. Changes in the physical Environment: * The Earth has continually changed since life first evolved. * Various changes in sea levels, the splitting of the continents and great changes in climate are just some of the environmental changes that life on earth have had to cope with, or become extinct. * Changes in the environment force species to either die out, or survive and diversify. An Example - The Peppered Moth: * Prior to the Industrial Revolution, the majority of the peppered moths were light coloured. They
Investigating how temperature affects the resistance in a wire
Aristide Mooyaart 11E Investigating how temperature affects the resistance in a wire Prediction / theory: All substances in the world are made up of protons, neutrons and electrons. All atoms have a nucleus in the centre that is made up of neutrons and protons, and a certain number of electrons circling around it; these electrons circling around the nucleus have a negative charge. These electrons orbit the nucleus in shells; they occupy different shells with the rules that: -The first shells (nearest to the nucleus are always occupied first -The maximum of electrons any shell can hold is 2n^2 (where n = the shell number) -The outer-most shell containing electrons can only hold a maximum of 8 electrons To demonstrate this here is a model of a metal atom (iron): All metals are known as n-type semiconductors as they all conduct electricity but all have resistance at room temperature. Metal atoms can bond together to form a giant structure, which is held together by metallic bonds; this means that there are many free electrons in these structures. This is because the metal atoms in the metallic structure have electrons on the outer-most shell that pass freely from one atom to another; these electrons can carry heat from one metal atom to another (making metals good conductors of heat). The electrons in these metal structures can be 'pushed' in one direction buy a lack of
Multi-bladed Pumps. Does the number of propellor blades affect the efficiency of a water pump?
Pumps & Physics Research and Rationale What's new? When I was thinking about which aspect of physics to investigate for my investigation, I knew it was a good idea to choose something that really interested me. At the time I was becoming more and more fascinated by subatomic particles. I liked the fact that much of it was new and not understood properly, unlike the classical physics that everyone associates the subject with. Unfortunately, high energy physics does not translate into good practical coursework. However, while reading Six Easy Pieces, a book adapted from Richard Feynman's famous textbook The Feynman Lectures on Physics, I noticed that a very common everyday phenomenon is still not properly understood by physicists. Encouraged by the prospect of discovering something new, I read on. Chaotic ideas Feynman wrote (on page 66) "There is a physical problem that is common to many fields, that is very old, and that has not been solved...It is the analysis of circulating or turbulent fluids...No-one can analyse it from first principles" "Wow - something science can't explain" I thought. I looked on the internet for further details and I found a poster from World Maths Year 2000 (http://www.newton.cam.ac.uk/wmy2kposters/march/), showing just the type of unpredictable fluid motion that Feynman was writing about. It's a new and exciting branch of maths called
To find which of the circuits, shown below, are most suitable to measure a range of resistances, which the meters (the voltmeter and the ammeter) could be used to measure.
How do I connect this Voltmeter? Aim To find which of the circuits, shown below, are most suitable to measure a range of resistances, which the meters (the voltmeter and the ammeter) could be used to measure. Prediction I did not know which circuit would be the most accurate, to start with so I did a preliminary investigation, which consisted of setting up the two circuits above and then just putting two resistors in each and working out the required resistance. I did not see at the time that different value of resistance would make much of a difference until I commenced with my calculations. I discovered by using resistance values of 2200? and 4700?, that Circuit Two was better. Circuit One 2200? = 2105? by meter readings 4700? = 4364? by meter readings Circuit Two 2200? = 2222? by meter readings 4700? = 4600? by meter readings As you can see from these initial findings Circuit Two is the better circuit for measuring resistance values according to the labelled resistance. Hypothesis The manufacturers' specifications as given on the Voltmeter and Ammeter are as follows: Ammeter - Maximum Current 2mA, resistance 40? Voltmeter - Maximum Pd 5V, Maximum current 100µA After inspecting the above apparatus I have decided that the smallest value of the Current that I can accurately measure is 1 x 10-4 A and the maximum is 2 x 10-3 A. Any higher than 2 x
Applied Science
APPLIED SCIENCE ASSIGNMENT 2 TASK 1(A) Experiment on diffusion Aim: to determine diffusion (in ordinary tap water). Apparatus: beaker, potassium permanganate and tin foil. Method: I filled the beaker (half) with ordinary tap water and I released the potassium permanganate into it from the thin foil. Results: within a matter of a few seconds to one and half minutes, the whole water turned purple beginning from the area where the potassium permanganate was dropped. Conclusion: this experiment showed the movement of potassium permanganate molecule all around the beaker of ordinary tap water thereby, concluding the fact that molecules would move from a place of higher concentration to a place of lower concentration (diffusion) passively. Experiment on osmosis The aim of this experiment is to determine osmosis. Apparatus: test tube, potato tuber, electronic balance, watch glass, different concentrated solutions of sucrose: 0.003m, 0.006m, 0.125m, 0.25m, 0.5m, 1m and water. Method: I cut the potato in six equal parts and I weighed them using the electronic scale. I then put each piece in different solution and I left them for 24 hours and I weighed them again. Result: Concentration of solution Original weight Weight after 24 hours water 1g 2.62g 0.003m 1g 2.21g 0.006m 1g 2.35g 0.125m 1g 1.91g 0.25m 1g 1.64g 0.5m 1g 0.36g .0m 1g 8.49g The
Investigating the Effect of pH on Enzymes
Investigating the Effect of pH on Enzymes Plan: My aim is to carry out an experiment that will let me deduce the affect that a varying pH will have on the rate at which the enzyme amylase will break down starch into its component parts, which are maltose and dextrins. Background: What is an Enzyme? Enzymes are substances that act as catalysts and so they increase the rate of chemical reactions. In biological systems reactions may occur very slowly or even not at all unless a catalyst is present and this is why enzymes are required. With an enzyme the product of the reaction will occur far faster even to a factor of at least one million. Unlike inorganic chemical catalysts, enzymes are specific. This means that one enzyme normally is used for one reaction. This is as each enzyme has a particular shaped active site, which the substrate (the molecule that is being broken down) will combine with. The shape of the active site depends on the structure of the whole enzyme. The Structure of Enzymes All enzymes are globular proteins, and so have a primary secondary and tertiary structure. The primary structure of a protein is the number, type and sequence of amino acids that make up a polypeptide chain. In the case of the enzyme that we are using (alpha-amylase) the polypeptide chain is around 496 amino acids in length. Each of these amino acids has the general formula
Biology coursework planning - the effect of lead chloride on the growth of cress seeds
Biology coursework planning - the effect of lead chloride on the growth of cress seeds Aim: To investigate the effect of different concentrations of a heavy metal chloride, namely lead chloride, on the growth of cress seeds. Introduction: Heavy metals compounds, such as lead chloride are able to dissolve in rain and enter the soils surrounding plants. Some sources of such compounds are exhaust fumes from vehicles, additives in gasoline and paints, fertilisers and mining. Lead chloride is able to accumulate in the soil at sufficient concentrations and is easily absorbed by plants. For plants, lead is a toxin and when present in significant amounts, can cause severe decreases in their growth as well as death. The toxicity of heavy metals is seen as the irregularities in the normal functioning of the plant rather than direct toxicity to plant cells. Symptoms include stunted growth and the yellowing of plants (called chlorosis). Heavy metals collect in different organs of a plant and produce variable effects. Lead disrupts the plant's plasma membrane structure as well as permeability (proteins in the membrane), osmotic balance (the intake of water and ions) and indirectly, plant metabolism (the availability of nutrients for chemical reactions.) These factors are discussed below in further detail. The root cells of a plant carry proteins called chelates in their cell
To find out how different concentrations of sucrose solution affect the incipient plasmolysis of different root vegetables until the isotonic point has been reached.
AS Biology Coursework Introduction: - to find out how different concentrations of sucrose solution affect the incipient plasmolysis of different root vegetables until the isotonic point has been reached. Prediction Osmosis is defined as the net movement of water molecules from a region of high water potential to a region of low water potential across a partially permeable membrane down the concentration gradient. A partially permeable membrane allows some molecule to diffuse through but not all, if the molecules are small enough like water molecules then they can diffuse through easily but large solute molecules can't pass through. The water molecules will diffuse both ways through the partially permeable membrane however the net movement will be to the side with a lower concentration of water molecules. Water potential is the potential of water molecules to diffuse out of a solution, also water molecules are more likely to diffuse out of a solution containing a higher concentration of water molecules and they are less likely to diffuse out of a solution containing a lower concentration of water molecules. Pure water contains the highest water potential which is zero kilopascals 0(?) All solutions have a lower water potential then pure water hence there water potentials are always negative, the more solute molecules present the lower more negative the water potential. The
Design an experiment to investigate the effect of temperature on the movement of a pigment through a membrane
Design an experiment to investigate the effect of temperature on the movement of a pigment through a membrane Hypothesis The tonoplast is the membrane that separates the vacuole from the rest of the cell. The membrane is selectively permeable and a phospholipid bilayer. The membrane is made up of phospholipids, which have a phosphate group and two fatty acid tails. The phosphate group is polar and hydrophilic, whereas the fatty acid tails are non-polar and hydrophobic. The fatty acid tails therefore try to get as far away as they can from the watery fluid in the vacuole and the watery cytoplasm, so the fatty acid tails point inwards and the phosphate heads point outwards. Also in the bilayer there are proteins, which can be intrinsic or extrinsic. Intrinsic proteins are proteins that span the full width of the membrane, whereas extrinsic proteins only go a small way into the membrane. The proteins provide structural support, act as carriers for water-soluble substances, can act as enzymes, form ion channels and they can act as receptors for hormones. Carbohydrate chains can join to the extrinsic proteins forming glycoproteins. These act as recognition sites. Carbohydrate chains can also join to the phospholipids forming glycolipids, this act as recognition sites and helps the stability of the membrane. Also there is cholesterol in the membrane this prevents leakage of water
