Investigating the Respiration of Yeast
Biology - Coursework Investigating The Respiration Of Yeast Factors That Can Affect It In order to alter the respiration of yeast, I will have to change a factor, this could be any of the following things - * Temperature * Amount Of Food (Sugar) * Amount Of Fluid (Water) * Different Types Of Yeast I have decided to investigate the effect of altering the temperature of the experiment. I predict that the rate of CO2 released will increase with the temperature. The theory behind this is quite complex. Energy is required for respiration (in this case, the transforming of Glucose (C6H12O6) into Carbon Dioxide (CO2)), so there must be a certain amount of energy to start the reaction. Known as 'Activation Energy'. This energy comes from heat energy in atoms, according to particle theory, as the temperature increases, the atoms will vibrate faster. However, adding certain enzymes to the reaction allows the activation energy to be lower. These enzymes require heat energy however to do this. In the human body, enzymes will denatureate over a temperature of 460 C, so, therefore, I will not allow the specimens to reach temperatures of above 500 C. There is no need for an oxygen intake, as this experiment requires Anaerobic Respiration The Equation For The Experiment Is - To carry out this experiment I will need: - * Electronic Scales * Conical Flask * Water Bath *
Plants And The Effect of Nutrient Deficiencies
Plants And The Effect of Nutrient Deficiencies Introduction Plants need a variety or nutrients to survive in the wild and to grow and survive properly. Each has different uses within the plant and all are vital for the plant to continue living and reproduce thereby ensuring the survival of the species, some of which are macronutrients e.g. nitrogen, and others that are micronutrients . Most nutrients not are absorbed through root hairs found on the plant, and enter through simple diffusion. Once inside the plant the nutrients can reach the stele through one of two methods. One of the methods is the use of the apoplast pathway, this involves soaking through the cell wall into the cell, once here it soaks into the next cell via the plasmadesma or pits found along the cell membrane, and continues this method until reaching the endodermis. The second methods available for use is the sinoplast pathway in which the nutrient soaks in and then out of the cytoplasm of each cell , continuing to do so until it reaches the endodermis. Once at this point the apoplast pathway is blocked and the nutrient must move through the cells using the sinoplast pathway. Once here it reaches the xylem and phloem cells and is free to move up and down the plant to where it is needed through transpiration pull, which is essentially the pull from water's cohesion from the leaves all the way down the
AS Edexcel Biology - Aim: To investigate the effect of caffeine on the heart rate of Daphnia (water fleas).
The effect of caffeine on heart rate. Aim: To investigate the effect of caffeine on the heart rate of Daphnia (water fleas). Background Information: Plants produce caffeine as an insecticide. Cocoa in South America, coffee in Africa and tea in Asia has all been used as 'pick-me-up' drinks containing caffeine. These days caffeine is used in a wide variety of soft drinks such as cola to enhance flavours. In addition to this, stimulant drinks such as Red Bull and Boost also carry high levels of caffeine as well as some weight-losing drugs and medicines such as Aspirin. IN humans, caffeine acts as a stimulant drug, causing increased amounts of stimulatory neurotransmitters to be released. At high levels of consumption caffeine has been linked to restlessness, insomnia and anxiety, causing raised stress and blood pressure. This can lead to heart and circulation problems. Hypothesis: I think that the Daphnia's heart rate will rapidly increase when the caffeine solution is added. This is because increases the amount of neurotransmitters released in the body so everything in the body will be working at a faster rate because of these. Planning: -Risk Assessment: 1. I need to be aware of weils disease so I will not come in to direct contact with the pond water and regularly wash my hands thoroughly throughout the experiment. 2. I will need to constantly keep my glassware on
Designing a data collection strategy The effect of temperature on the rate of respiration of yeast.
Skill A - Designing a data collection strategy The effect of temperature on the rate of respiration Aim I am going to investigate the question, does a changing temperature have an effect on the rate of respiration in yeast cells? A simple and safe experiment will be conducted by changing the temperature of the yeast and glucose solution, and recording the amount of carbon dioxide produced. Various temperatures will be created in a thermostatically controlled water bath, and a range of temperatures will be used to make the experiment as reliable as possible. Prediction I predict that with every 10°C, the amount of gas which is produced will be doubled. The Q10 of yeast is 2, therefore with every 10°C increase, it will double the rate of reaction, increasing the amount of gas made by 2.1 Q10 is the respiration rate at 10°C/respiration rate at t°C. I believe this will happen because, as the temperature rises there is an increase in kinetic energy of the enzymes in the yeast cells which creates more chances of enzyme substrate complexes being formed, because there are more collisions happening between the enzymes and substrates. This in turn will increase the reaction rate and more carbon dioxide will be produced. So I believe that as temperature increases there will be more gas produced. Each reaction has an optimum temperature where the maximum amount of enzyme
How can we prioritise species for conservation?
How can we prioritise species for conservation? Species becoming extinct: Species are facing various problems key to their survival such as destruction of animal habitats, damage to the natural environment of living things, for example trees are cut down to build homes, , Oil spills, acid rain and water pollution also add to the destruction of habitats. Moreover another cause for extinction is when animals are over-hunted for their meat, fur and other valuable parts.Another cause could be'when animals or plants arrive into a new habitat from a foreign place they sometimes introduce diseases that the native species can't fight. These "exotic" species can also prey on the native species'.[1] 'Ahmed Djoghlaf, head of the U.N. Convention on Biological Diversity stated that, "Extinction rates are rising by a factor of up to 1,000 above natural rates. Every hour, three species disappear. Every day, up to 150 species are lost. Every year, between 18,000 and 55,000 species become extinct. The cause: human activities." he said '.[2] Why conserve species: There are many advantages in conserving species not only the fact that we benefit from the diversity of animals and plants, as majority of our plants such as crops. Domestic animals are bred from wild relatives and can importantly benefit from the immense, scarcely tapped wild gene pools. Moreover Important requirements such as
Catalase Investigation - Core practical
Investigation into the amount of potato discs effecting oxygen produced. Introduction The purpose of this investigation is to find out whether the amount of Catalase affects the volume of oxygen produced. The Catalase I will use is in potato. It contains catalytic enzymes such as Catalase. To measure the volume of oxygen produced, I will use an upturned syringe filled with water and a tube leading from the reaction in the test tube. The oxygen will collect in the syringe and give us a measurement. For my Hypothesis, I predict that adding more potato discs will give more oxygen produced. This is because Catalase increases the rate of reactions as it is an enzyme which is a natural catalyst. This will speed up the decomposition of Hydrogen peroxide. Hopefully, this experiment will lead to a conclusion reflecting the statements made in my prediction. Variables Variables are factors in an experiment which can be altered or varied. An independent variable is a factor which is changed to show the purpose of the investigation. The independent variable for this experiment was the amount of potato discs in each solution. This meant altering the amount of potato would affect the dependant variable. The dependant variable in the investigation was the volume of oxygen gas produced. This meant I could observe this dependant variable and record the results to make a conclusion. In the
The Ways in Which Organisms Use ATP
The Ways in Which Organisms Use ATP ATP, the standard abbreviation of Adenosine-5'-triphosphate is a multifunctional nucleotide used in cells as a coenzyme, and can be best summarised as the standard energy currency universal to all organisms, and as such is utilised in metabolic (and other) processes throughout the cells of organisms, and is highly adapted to its function therein due to its high instability in aqueous solutions (eg tissue fluid) due to its easily hydrolysable phosphoannhydride bonds which when broken release a proportionally huge amount of energy. ATP is required during the contraction of skeletal muscle. ADP is released by the myosin head, this allows it to change shape thereby pulling the actin filament across itself. In order to detach the myosin molecule (for it to bind to a myosin binding site further along the actin) ATP binds to the myosin head, where it is hydrolysed to release ADP (which remains on the head) and inorganic phosphate. The energy released allows the myosin head to resume its normal position prior to the release of its ADP molecule, ready to bind further along the actin filament. Furthermore, ATP is utilised elsewhere within the same process, as it is used by carrier proteins on the membrane of the sarcoplasmic reticulum as a source of energy for the active transport of Ca2+ ions into the sarcoplasmic reticulum. It is when these
Effects of different concentrations of ethanol on the heart rate of the water flea
Effects of different concentrations of ethanol on the heart rate of the water flea In this experiment I will be looking at the effects of different concentrations of ethanol on the heart rate of the water flea, Daphnia because using humans in a study to test the effects of Ethanol on heart rate would not be ethical. Daphnia, like many animals, are prone to alcohol intoxication, and make excellent subjects for studying the effects of the depressant on the nervous system - due to the translucent exoskeleton, and the visibly altered heart rate.Ethanol is a small molecule, RMM of 43, so it crosses cell membranes by simple diffusion. The exoskeleton of Daphnia is not waterproof, so there are no waterproof waxy layers to cross. The gills are particularly thin-walled and optimised for diffusion. They live in various aquatic environments ranging from acidic swamps to freshwater lakes, ponds, streams and rivers. They are tolerant of being observed live under a microscope and appear to suffer no harm when returned to open water. The experiment consists in preparing 5 different environments to put the water flea in, and observe how the heart rate responds to each change; the change will be the increase of ethanol concentration %. This will be the independent variable. The dependent variable is the heart rate of the Daphnia. Hypothesis : Ethanol will decrease the heart rate of the
Investigation into the Ecology of a small stream in Tillingbourne.
Investigation into the Ecology of a small stream in Tillingbourne Ecology is the scientific study of the interactions between organisms and their environment. Invertebrates are interesting organisms to investigate because they represent an enormous diversity of body shapes, survival strategies, and adaptations. Many invertebrates require clear, cool water, adequate oxygen, stable flows, and a steady source of food in order to complete their life cycles. My aims are to investigate the abundance and distribution of freshwater invertebrates in the stream, and to measure abiotic factors such as oxygen levels, in the stream. Prediction I predict that there will be a higher number of organisms at the edge of the stream, than in the middle. Introduction I make this prediction as there is increased vegetation at the edge of the river meaning that more oxygen is released as the plants photosynthesise, from which organisms can respire. The vegetation also provides food for herbivores and detritivores, and shelter from light, predators, and the current. Therefore the edge of the river is generally a more desirable place for organisms to live, so theoretically more should be found there, than in the middle of the stream. The Location The stream in which I carried out my investigation on the 18th October 2001 was part of the River Tillingbourne at Abinger Hammer, located south of
Grazing cattle is less efficient than growing crops, discuss this point.
Grazing cattle is less efficient than growing crops, discuss this point. "The beef in just one Big Mac represents enough wheat to make five loaves of bread." This just shows that growing wheat is more efficient than grazing cattle as the five loaves lasts, on average for a family of four, about three weeks whereas a Big Mac only lasts one person a matter of ten minutes, if that! In this essay I am going to discuss whether or not grazing cattle is less efficient than growing crops. There are many perspectives to this argument. From a biologists point of view, plant foods are far more energy efficient than animal products because when you eat meat, a vast amount of energy is lost through the food chains, whereas when you eat plant foods such as wheat, no energy is previously lost because plants are the producers of the food chains. On the other hand, meat is easy to digest and therefore, eating meat is also a way of converting energy that we actually can't eat, such as the energy from grass, even though there is not much energy left. A recent report released by vegetarians stated; "Growing crops is at least five times more energy efficient than crazing cattle, twenty times more efficient than raising chickens, and over fifty times more efficient than raising feedlot cattle! In this way, eating animal products clearly wastes energy resources that were naturally formed over
