Investigating the optimum concentration of a solution of Urea [(NH2)2CO] and Ammonium Nitrate [(NH4NO3] nutrition solution (as inorganic fertilisers) required for optimum plant growth and a sustained yield of rice.
Investigating the optimum concentration of a solution of Urea [(NH2)2CO] and Ammonium Nitrate [(NH4NO3] nutrition solution (as inorganic fertilisers) required for optimum plant growth and a sustained yield of rice. Introduction: Hydroponics is the growing of plants in water instead of soil. For most effective results, the water must be enriched with nutrients and sometimes requires to be oxygenated. For a plant to receive a well balanced diet, everything in the soil must be in perfect balance. Rarely, can you find such ideal conditions in soil due to contamination and biological imbalances. But with hydroponics, water is enriched with these very same nutrient salts, creating a hydroponic nutrient solution that is perfectly balanced. Also, very little water is lost to evaporation in a hydroponic system, making hydroponics very useful in drought stricken areas. 'Scientists can use hydroponics to test how different nutrients affect a plant. With hydroponics, a scientist can measure exactly how much nutrients the plant is getting and can give the plant a deficiency or overabundance of a certain macro or micronutrient and determine precisely how it affects the plant's growth.' Apparatus: * 4 Plastic storage totes * Regular fish aquarium air pump * Air stones * Long pipes * Long grain brown rice * Deionised water * Urea solution [ (NH2)2CO] (aq) * Ammonium Nitrate
To investigate how concentration of the enzyme catalase in celery extract affects the rate of reaction with hydrogen peroxide
Aim: To investigate how concentration of the enzyme catalase in celery extract affects the rate of reaction with hydrogen peroxide Reaction: 2 H2O2 (aq) --> 2 H2O (l) + O2 (g) Scientific Knowledge: Enzymes are protein molecules which can be defined as biological catalysts. A catalyst is a molecule which speeds up a chemical reaction. Nearly every metabolic reaction which takes place within a living organism is catalysed by an enzyme. Catalase is present in all living cells. Enzymes are globular proteins and like all globular proteins, are coiled into a three-dimensional shape with hydrophilic side chains, ensuring solubility. Enzymes also contain an active site (usually a cleft or depression) to which a substrate molecule can bind to. The shape of the active site is complementary to the shape of the substrate molecule and each enzyme is substrate specific, meaning each type of enzyme will only act on only one type of substrate molecule. Like all catalysts, enzymes work by lowering the activation energy (?G‡) for a reaction, thus dramatically accelerating the rate of the reaction. Catalase breaks the chemical hydrogen peroxide down to water and oxygen. Catalase is found in all cells and protects them from this dangerous waste chemical. I will use the catalase found in celery extract for this investigation. The substrate (hydrogen peroxide) and the catalase molecules
This assignment is divided into two sections, the first deals with the isolation and identification of individual microbes. The second part looks at the growth and monitoring of microbes. Section 1 Identification of microbes: A case study Task 1 Practical: Aseptic technique Task 2 Write a step-by-step guide on how to perform an aseptic technique, include a reason and explanation of the precautions taken. Make reference to the health and safety legislation covering micro-organisms. All of these steps are to ensure that cross contamination does not occur and cause the results to be misleading. • Restrict micro-organisms present in specimens or cultures to the vessels in which they are contained. • Prevent environmental micro-organisms (normally present on hand, hair, clothing, laboratory benches or in the air) from entering specimens or cultures and interfering with the results of the studies . Make sure bench is clutter free. So that belongings do not get contaminated / or the sample doesn't get contaminated. 2. Hair should be tied back. To avoid contamination or accidents, such as hair catching fire from a Bunsen burner. 3. Lab coats should be worn. To avoid cross contamination 4. Bags and coats should be stowed away under the bench or in a cloakroom. To avoid accidents / cross contamination 5. Wipe bench down with alcohol. To sterilise working area before
Experiment. Hypotheses: The higher the concentration of caffeine the higher the heart rate of the daphnia.
The effect of caffeine concentration on daphnia's heart rate Hypotheses: The higher the concentration of caffeine the higher the heart rate of the daphnia. Biological information: caffeine speeds heart rate, and circulation. Caffeine is a stimulant drug, which causes increased amounts of stimulatory neurotransmitters to be released. It belongs to a Group of chemicals called methylxanthines. Caffeine and similar compounds also inhibit a class of enzymes known as cyclic nucleotide Phosphodiesterases. These enzymes are, in part responsible for degrading a stimulatory signal produced when excitatory neurotransmitters activate different neurons in the central nervous system (CNS). When they are inhibited by caffeine, the stimulatory signal remains active for a longer period of time resulting in a greater sense of alertness (a CNS effect). Independent variable: concentration of caffeine 0- 0.5% Dependant variable: this is the heart rate (BPM) Controls: 0% caffeine to check that water alone does not have an effect on the heart rate compared to pond water. Other fixed/controlled variables: The temperature must always stay constant this means that it must be fixed at room temperature. This can be done by removing the light source from the microscope when not counting because it increases the temperature which leads to an increase in metabolism and therefore an increase in the
Introduction Yeast is a microscopic fungus, of which there are hundreds of species. It is extremely important brewing ingredient because different strains give different beer types their distinctive and characteristic flavors. When a brewery has found an ideal yeast, it will be retained for many years. However, fresh batches are produced regularly from samples kept under special laboratory conditions to prevent the built up of microbiological contamination. (Just as milk can go sour - yeast and bacteria can also contaminate beer). Individual yeast cells are invisible to the naked eye, and are carried in air current. When they grow on a suitable food source (for example fruit, such as grapes and plums) they form 'colonies' of cells. (These can be seen as a fine white powdery film on the skins of the fruit). Yeast can feed on a variety of sugars, converting them into energy in order to grow and multiply. When it first grows, the yeast cells need a supply of oxygen in the same way a animals do when they convert sugar into the carbon dioxide and energy. If animals run out of energy they die. But in the absence of oxygen, yeast obtains its energy from 'anaerobic fermentation' in which sugars are converted to alcohol and carbon dioxide. Most importantly for the brewery, yeast produces a variety of flavoring components (through side reactions), which help give the beer its
PLANNING Initial Method . Prepare 8 sterile Petri dishes with a perfectly fitting circle of cotton wool and filter paper, this will sit on top of the wool 2. A control dish must also be set up using the same steps as above 3. Weigh out 8 different salt measures, at 0.25, 0.5, 0.75, 1, 1.25, 1.5 and 1.75 4. Measure out 8, 50ml beakers of distilled water 5. Add the one measure of salt into a beaker (1 beaker for each weight) and stir until the salt is dissolved and cannot be seen 6. Add one drop of Plant nutrient growth (e.g. baby bio) to each solution 7. Add each solution into individual Petri dishes which were made up earlier on, make sure the cotton wool and filter paper are allowed a small amount of time to absorb as much water as possible before the next step 8. Add 10 Cress seeds to each of the 8 solutions and place the lid on the dish 9. Place the dishes in are area which is well lit by natural light 0. Check the dishes each day for a week and top up each dish with the same solution if it is becoming dry, add the same amount to each dish (record what you add) 1. Count and record the percentage I chose to carry out my method in this fashion as it gave me the best way to see which salt concentration had the biggest effect. I chose 8 solutions as it gives me a good range to monitor the salinity effects. The solutions are based on findings in earlier research
Making up between 70 and 95% of the mass of a cell, and covering over three quarters of the planets surface, water is one of the most important compounds on this planet. A single water molecule is made up of one oxygen atom covalently bonded to two hydrogen atoms. Covalent bonds are formed by sharing electrons between the outer shells of the oxygen and hydrogen atoms. However, what makes water so unique is the fact that it remains a liquid at room temperature. Many similar sized molecules (ammonia has a molecular mass equal to that of water-18) remain in their gaseous form at this temperature. The reasons for this unique thermal property are hydrogen bonds. The nucleus of an oxygen atom is larger and therefore contains many more protons that that of a hydrogen atom. Therefore, the electrons shared in the covalent bond between the oxygen and hydrogen atoms have a greater affinity for the oxygen atom than either hydrogen atom. This pulls the electrons closer to the oxygen atom and away from the hydrogen atoms resulting in the oxygen atom having a slightly negative charge and the hydrogen atoms developing slightly positive charges. These slight charges mean that when water molecules are close together, positively charged hydrogen atoms are attracted to the negatively charged oxygen atoms of a different water molecule. These attractions are known as hydrogen bonds and
Energy Presentation Notes Name: ____ The big picture: . Energy is defined as: ____ability to do work_____________ 2. Most energy resources on Earth originally derived their energy from the ___sun__. For each of the following identify their connection to the sun's energy. a. Fossil fuels __photosynthesis fueled plant growth which then decayed______ b. Wind ___sun heats the atmosphere causing convection currents____________ c. Hydroelectric/tidal _____________________________________________ 3. Ideal fuel sources are high in Potential energy. Potential energy is _stored_ energy. Identified where the potential energy is stored in each of the following fuel sources. a. Fossil fuels (oil/coal/methane) ___chemical bonds of molecules_______ b. Nuclear _____binding energy in nucleus & mass --> energy conversion_______ c. Hydroelectric _____height differential and gravity_____________ 4. Kinetic energy is energy of __movement__ and can be used to do work. 5. To compare fuel sources it is important to evaluate costs, availability, efficiency and environmental impacts. Fossil Fuels: . The three major fossil fuels used in energy production are: _coal, petroleum & methane_ 2. Which one is formed primarily from aerobic decomposition of plants underground fossilized over millions of years? _coal_ 3. Which one is formed primarily from anaerobic decomposition of marine
The effect of Caffeine on the heart rate Aim: To investigate the effect of caffeine on the heart rate of Daphnia (water fleas). Background Knowledge: Daphnia are tiny water fleas with an average size of less than 3mm. Daphnia are translucent invertebrates (have no backbone) and their outer body is made up of a hard shell which protects the whole body except for the head. Daphnia's are found in ponds, lakes, and calm streams where the temperature is between 21-24°C (68-71°F). Daphnia reproduce rapidly. Up to 13 billion related offspring can occur within 60 days for one Daphnia. In winter the eggs are thick-shelled and thin shelled in the summer. In warmer temperatures the eggs will hatch female, and in colder temperatures the eggs will be male. Daphnia's will be used to experiment the on as although they are tiny in size their heart beat can be examined through a microscope because of their transparency. Caffeine is produced by plants as an insecticide. Cocoa in South America, coffee in Africa and tea in Asia has all been used for hundreds of years to produce "pick me up" drinks containing caffeine. These days, caffeine is used as a flavour enhancer in a wide range of cola and other soft drinks. In addition, it has medicinal uses in aspirin preparation, and is found in weight-loss drugs and as a stimulant in students' exam-time favourites like Pro-plus and Red Bull.
Investigating the effect of temperature in respiration in maggots. Aim: This is an experiment to investigate how temperature effects the respiration rate in maggots. The formula: The simple formula of respiration is: C6H12O6 + 6O2 6H2O + 6CO2 + ENERGY GLUCOSE + OXYGEN WATER + CARBON + ENERGY DIOXIDE The Collins concise English dictionary explains that respiration is 'the processes by which a living organism...takes in oxygen, distributes and utilizes it in oxidation, and gives off products, esp. carbon dioxide'. Background information: Respiration is the chemical process of releasing energy from organic compounds in living cells. The organic molecules are broken down through a series of steps to act as fuel. The most common organic compound for most cells is glucose however, some cells can break down fatty acids, glycerol, and amino acids in respiration. The energy gained from respiration is used to synthesise ATP (adenosine triphosphate) which is required throughout the body, in order to replenish ATP stores. There are two types of respiration; anaerobic and aerobic. Aerobic respiration occurs when oxygen is freely available, whilst anaerobic respiration occurs when free oxygen is not present, and the process is altered. We will investigate aerobic respiration. There are four main stages of respiration (when breaking down