Effect of nitrate concentration on the growth of Duckweeds
Introduction & Method At the beginning of the experiment, I put on a lab coat to protect myself from any danger that may occur. I made sure that all my equipments were clean and dry before I started, and I also measured the temperature of the room to confirm it was around room temperature. I then made sure that the ice cube tray was clean, I put a little label on one end of the tray to indicate my starting point row of the ice cube tray. I then made a little note to myself that the label indicated the row which will contain the 0.0% x 10-3 concentration of nitrate in the solution, and the rows onwards will contain the concentration of nitrogen in solution in ascending orders which I will use (0.0, 0.4, 0.8, 1.2, 1.6 and 2.4 % x 10-3). I Whilst pouring the solutions into a glass beaker I put on goggles and gloves to protect my eyes and hands from any contacts with the ammonium nitrate solution, as any contact can lead to irritation of the skin and eye. I poured 80-90cm3 of the 1st concentration which contained 0.0% x 10-3 of nitrate into a 100cm3 glass beaker. Next I used a clean syringe to measure out 25cm3 of the solution into the 1st well (near my label). The tray had 3 wells in a row and there were 6 rows, I repeatedly added 25 cm3 of the same ammonium nitrate solution into the remaining two wells of that row, so that I will obtain a result of three replicates with each
To make sure we have plenty of energy in the future, it's up to all of us to use energy wisely. We must all conserve energy and use it efficiently. It also ups to those of you who will want to create the new energy technologies of the future.
Fossil fuels enable human ingevnovnuity and gave rise to the Industrial Revolution. Coal-fired electricity empowers humankind's evolution in the Information Age. Humans harness earth's abundant fossil fuels resource - formed from the remains of prehistoric plant and animal life - as our primary source of energy. In a very real sense, using fossil fuels recycles the product of solar energy locked-up during photosynthesis over millions and millions of years. Whether using coal to make most of the world's electricity, petroleum as the lifeblood of transportation or, along with natural gas, as a feedstock for myriad industrial and commercial uses, fossil fuels are keys to our industrial evolution. Where Fossil Fuels Come From There are three major forms of fossil fuels: coal, oil and natural gas. All three were formed many millions of years ago during the time of the dinosaurs -- hence the name fossil fuels. Fossil fuels are made up of decomposed plant and animal matter. Plants change energy they receive from the sun into stored energy. This energy is food used by the plant. This is called photosynthesis. Animals eat plants to make energy. And people eat animals and plants to get energy to do work. When plants and dinosaurs and other ancient creatures died, they decomposed and became buried, layer upon layer under the ground. It took millions of years to form these
effect of temperature on the rate of respiration in yeast
Effect of temperature on the rate of respiration in yeast Aim: My aim is to investigate the effect of temperature on the rate of respiration in yeast by using a universal indicator. Background theory: Enzyme: Enzymes are organic catalysts that speed up the rate of a chemical reaction without being permanently altered in the process. Enzyme Characteristics * Lower the energy of activation * Form reversible complex with substrate. * Not consumed in the reaction therefore they are effect in small amounts * Very specific - (Induced fit hypothesis) react with only a single substrate. * Many need cofactors, such as certain vitamins, to be activated. * 2000+ enzymes per cell, different cells have different enzymes. * Enzymes are produced by genes. * Genetic disorders are the result of faulty enzymes. * Operate best in optimum conditions of pH, temperature, etc. * Are controlled by feedback mechanisms. Enzyme mechanism: Key and theory: The substrates (reactants) are attracted to the enzyme molecule. They join forming an enzyme-substrate complex. The reaction occurs on an area of the enzyme molecule known as the active site producing new substrates(s) or products. Induced fit hypothesis: The attraction of the substrate and enzyme form an enzyme-substrate complex. It was originally referred to as the Lock and Key Enzyme Theory. The current theory
Fighter Pilot A Statistical Analysis of Reaction time and its Correlation with Dominant & Non-Dominant Hands
Fighter Pilot A Statistical Analysis of Reaction time and its Correlation with Dominant & Non-Dominant Hands Introduction This experiment seeks to determine reaction times in two groups of matched subjects; dominant and non-dominant hands, using the ruler drop test. Reaction time experiments are performed to measure the alertness of the mind and will give an indication of the speed of the reflexes that different groups of varied individuals have. The experiment tests how long it takes the brain to translate visual information into the voluntary motor commands, actions which lead to a ruler being grabbed. The shorter the length at which the ruler is grabbed, the shorter time and therefore the faster the person's reaction. The controls of these processes within the human body are the responsibility of the nervous system which is the seat of voluntary and involuntary movements along with language, emotion and memory. (1) The experiment begins with an environmental stimulus via light reflected from a moving ruler being dropped from a height above the subject's hand. (1) This transmits into a sensory nervous impulse within the optic nerve. Beginning in the retina of the eye, information is detected by photoreceptors (rods and cones) they relay the visual signals on to bipolar cells which transmit on to ganglion cells. (2) The axons of all ganglion cells in the retina of each
'An investigation into the ability of two strains of the yeast Saccharomyces cerevisiae to utilise different carbon sources as substrates for cellular respiration'.
'An investigation into the ability of two strains of the yeast Saccharomyces cerevisiae to utilise different carbon sources as substrates for cellular respiration' Introduction The purpose of this investigation is to compare the ability of two different strains of yeast to respire, when using different sugars as respiration substrates. Considering the lengths that have been reached to develop varieties of yeast with greater suitability and effectiveness for very particular fermentation purposes, it seems reasonable to suppose that two different strains of the same species of yeast, selected for their different fermentation properties, have developed requirements that are not uniform. As a result of the selection and development process, yeast best suited to ferment in a given application, possess a range of different characteristics. One such characteristic may be the ability to metabolise different carbon sources at different rates. This quality is important because in each application where different respiration substrates are available, a specific strain of yeast may be required. Yeast unable to utilise the available carbon sources will have undesirable fermentation rates, and therefore may not be selected for use in that application. The two yeast here compared, have two such different applications. The first yeast from the Saccharomyces cerevisiae variety is of the
An investigation into the effect of different sugars on respiration in yeast.
An investigation into the effect of different sugars on respiration in yeast. I am going to carry out an experiment, measuring the effect of different sugars on the respiration in yeast. In order to make a justified prediction I have researched different aspects of scientific knowledge, including respiration, yeast, sugar structure, enzymes and the collision theory. Glycolysis http://people.eku.edu/ritchisong/301notes1.htm Glycolysis is the splitting of a monosaccharide into two molecules of pyruvate. It takes part in the cytoplasm of a cell. Glycolysis begins with a monosaccharide with six carbon atoms, and ends with two molecules of pyruvate, each with three carbon atoms. For the first steps of glycolysis, energy from ATP is needed. However, energy is released in later steps to generate ATP. For every molecule of glucose, a net gain of two molecules of ATP is produced. The first stage of glycolysis is called phosphorylation, and results in hexose bisphosphate. This is shown in green on the above diagram. Hexose bisphosphate then breaks down into two molecules of triose phosphate. Hydrogen is removed from the triose phosphate and transferred to NAD to produce reduced NAD. These hydrogen's can then be used in oxidative phosphorylation to produce ATP. The end products of glycolysis are pyruvates, which still contains a lot of chemical potential energy. There are two
Home Economics - Why is nutrition important to sports people?
In order to obtain an idea for a task I could research, I decided to do an initial brainstorm of all the areas that would be possible to complete the project on (see fig1, next page). The factors that would affect my decision of what area to choose, were how easy it would be for me to research the topic, whether I knew people I could speak to about it and whether it was something that interested me. Because of these, I decided to research into nutrition for rowing. This was because I am a rower myself which meant that it would interest me, I would already know about the topic and I knew a variety of people who would be able to provide information and help on the subject. For research: To start the project I needed to carry out some preliminary, general research into the sport and its demands. The following are some things I needed to research: o Sports nutrition o Nutritional requirements of a normal person o Nutritional requirements of a rower o What a rower should eat on the day of, and during the week before, a race. Preliminary research Sources To ensure that I could gat a balanced set of information I decided to use data from several media types. These could include magazines, people, websites, books and companies. The following are some sources I thought would be useful: o ARA (amateur rowing association) o Internet - including rowing websites, BBC website,
Investigation on the size of Limpets.
Investigation on the size of Limpets Abstract: During my preliminary investigations, I established that sheltered and exposed rocky shores, differed immensely in their size of Limpets. Thus I was inspired to compare the size of Limpets on the sheltered rocky shore, Frenchman's Steps. The background knowledge and preliminary work enabled me conclude the following hypothesis; there will be a statistically significant difference between the size of limpets found on the sheltered rocky shore at two different vertical heights. I decided to look at 3M and 6M above chart datum for my investigation, as looking at the profile graph (appendix) the number of limpets was high at that chart datum. Aim: To determine if there is a difference in the size of limpets at two heights in there Vertical range. Scientific Background Limpets are animals that belong to the family Patellidae, subclass Prosobranchia of the phylum Molluscs. They have a strong, conical shell composed mainly of calcium carbonate, protecting the internal tissue, underneath which is a sucker, also known as the limpet foot, which allows limpets to adhere to rock surfaces, as shown in the photographs. Limpets are usually immobile unless they are foraging and so zonation is less apparent. As can be seen from the pictures above, limpets have a hydrodynamic shape so that resistance to water flow is reduced. This
Find the relationship between amount of fat and amount of energy produced in different foods.
July 2001 Biology Coursework Year 10 Aim Find the relationship between amount of fat and amount of energy produced in different foods. Planning I am going to ignite different foods and see how much heat energy they give out. The food that causes the biggest amount of change in temperature will have the most amount of energy. However, calculations have to be carried out to create an average energy output per gram. Variables Independent Variables: This will change from food to food, thus giving me a range of different results. In this experiment it will be type of food. Dependant Variable: This is the amount of Energy per gram which can be calculated Controlled Variables: These are the things that will keep the same, in order to sustain a fair test. These are; * Apparatus * Type of boiling tube * Distance of boiling tube from Bunsen burner * Distance of food from boiling tube * Amount of time taken to move ignited food to boiling tube Fair Test It is essential that I keep it a fair test in order to sustain accurate results for comparison at the end. To ensure a fair test, I must keep the controlled variables for every test I do. The apparatus must all be kept the same because there may be some minor differences in insulation properties, or measure of accuracy between them. If this were to happen, it would prevent me from sustaining accurate results. The same
Biology coursework investigation: Comparing the length of ivy leaves (Hedera helix) in areas of greater illumination and shade
Biology coursework investigation: "Comparing the length of ivy leaves (Hedera helix) in areas of greater illumination and shade" Abstract The aim of this study was to compare the length of leaves of ivy plants (Hedera helix) climbing on two Hornbeam trees (Carpinus betulus) in two different light intensities. The hypothesis was that the lengths of Hedera helix exposed to a higher light intensity ("sun leaves") would be shorter than Hedera helix exposed to a lower intensity of light ("shade leaves"). The light intensity was measured using a light meter and the lengths of the midrib vein of 30 leaves were measured from each of the two trees. The method describes how leaves were chosen to ensure that they were approximately the same age. The results were analysed using a students t statistical test and it was concluded that there was a significant difference between the lengths of the two groups of leaves. The main reason for this was concluded to be the structural differences in the Hedera helix in the sun and shade. Background information on Hedera helix Previous investigations have shown that there are structural differences between the leaves of ivy in areas of high light intensity and areas of low light intensity. Shade leaves of ivy are typically thinner than sun leaves and also have a larger area in comparison. This is due to them having a thinner cuticle and one layer
