How Abiotic Factors Present In an Ecosystem Affect the Organisms
HOW ABIOTIC FACTORS PRESENT IN AN ECOSYSTEM AFFECT THE ORGANISMS Mustafa Ganijee Abiotic factors are physical factors (non-living) factors that affect the distribution of organisms in their habitats. The abundance and distribution of a species is determined by whether levels of one or more physical and chemical factors go above, or fall below, the levels tolerated by the species. The figure below shows how the performance of any species is affected by an abiotic factor. Physical factors affecting organisms can be divided into 4 main categories: * Climatic - temperature, light, wind and water availability * Edaphic - factors related with soil * Topographic - altitude, aspect and inclination * Others - wave action etc Temperature Environmental temperatures influence the ability of organisms in an environment to survive and reproduce, especially if the organisms are ectotherms (cold blooded), e.g. the determination of sex in alligator and crocodile eggs. Most living organisms have an optimum temperature range within which they can survive (optimum rate of reaction and enzyme activity). The main source of heat is the sun via radiation. This factor will be affected by the habitat's latitude, the season of the year, time of the day and its aspect. Very low temperatures cause damage to cells due to formation of ice crystals and very high temperatures denature enzymes. Due
Ethics and Energy
Ethics and Energy Just over 100 years ago man kinds yearn for progression both on an industrial and technological scale was almost their primary objective of existence. It seemed that no environmental, natural or human issue was too large or important in contrast to the larger picture of progression and gain of knowledge. Mankind became greedy with power and had little if any regard for the damage that they may do to mother earth for the generation to come. More, more, more was the philosophy and where it came from and whom it affected was brushed under the carpet like yesterdays dust. As the industrial revolution, Second World War and nuclear age dawned upon mankind, daily advancement was at such a rate in leaps and bounds that it seemed there would never be any issue of ethics. When finally the world realized with a difficult awakening of environmental disasters and depleted natural energy such as coal, oil and gas that we were venerable to our own demise; slowly but surely but surely we started to take sight of our responsibility to ourselves, our children and the environment. In the 21st century we have started to understand that we have used over 50% in the last 100 years of the earths natural energy and need to find a renewable energy source. Of course there is technological findings and advancement in the fields of wind solar, geothermal, tide and nuclear power
Industrial Enzymes
Industrial Enzymes Industrial uses of enzymes Many of the reactions catalysed by enzymes have commercial uses. Previously, these reactions were made to happen without enzymes by using heat and/or strong acids but enzymes offer the following advantages: They are specific in their action and are therefore less likely to produce unwanted by-products. They are biodegradable and so cause less environmental pollution. They work in mild conditions i.e. low temperatures, neutral pH and normal atmospheric pressure, and are therefore energy saving. However, the last advantage can also be seen as a disadvantage as their conditions must be stringently controlled or the enzyme may become denatured. To be effective in a production process the enzyme molecule must be brought into maximum contact with the substrate molecules. The solutions can be mixed in suitable concentrations or immobilisation of the enzyme may be used. This involves attaching the enzyme to an inert surface such as plastic beads and then bringing the surface into contact with a solution of the substrate. Immobilisation has the advantage that the enzyme molecules can be used over and over again, with the result that a lot of product can be made from a relatively small amount of enzyme. An example of the use of immobilisation is in the use of lactase. This enzyme hydrolyses lactose (milk sugar), into glucose and
Experiment To Investigate the Plasmolysis Rate and Concentration of Sucrose Solution In the Onion Cell
Experiment to investigate the plasmolysis rate and concentration of sucrose solution in the onion cell Neena Kim SFC1A Date of the experiment : 1st September 2001 Objective In the onion cell, there is cell sap which has a certain concentration of materials. Depending the concentration of the outside of the cell, the cell can be plasmolysed at the different rate by osmosis. Hypothesis The cells will be plasmolysed more as the concentration increases. And incipient plasmolysis is the point when 50% of the cells are plasmolysed. Around 0.35M point, the rate of plasmolysis is the greatest. Apparatus Onion bulb 6 petri dishes 6 test tubes test tube rack wax pencil six 10cm graduated pipettes six beakers fine brush distilled water M sucrose solution fine forceps paster pipettes slide and cover slips microscope graph paper lazor blade tile procedure label six % of plasmolysed cells in the onion concentration of sucrose solution st 2nd 3rd average 0.2M 0.0 3.6 .7 .77 0.3M 5.8 22.0 22.1 9.97 0.35M 46.8 56.3 38.5 47.18 0.4M 69.3 54.5 57.3 60.40 0.5M 94.6 91.2 89.2 91.70 .0M 98.7 95.1 96.0 96.67 Table of the percentage of the plasmolysed cells in the onion and the concentration of sucrose solution used Limitation factors . The standard of plasmolysed cell was too vague. In truth, we cannot exactly judge whether
Decomposition of H2O2
Decomposition of H2O2 Catalase disproportionates: 2H2O2 to 2H2O + O2, H2O2 is a powerful oxidizing agent and is potentially damaging to cells. By preventing excessive H2O2 build up Catalase allows important cellular processes which produce H2O2 as a byproduct to take place safely. Question:I know that, in the reaction of the enzyme catalase with hydrogen peroxide, the rate of reaction should double with every 10 degrees Celsius increase in temperature. Why? The kinetic theory explains why the rate of chemical reactions will increase with temperature. As the temperature increases the movement of reactant molecules also increases leading to more successful collisions which result in reactions. Studies have led to a general rule of thumb which says that the rate of a reaction doubles for each 10 degree Celsius rise in temperature. The above has also been shown to be true of reaction catalysed by enzymes when other conditions, such as concentration of enzyme and substrate, are constant but it is important to remember that this will only be true between approximately 4 degrees and 50 degrees Celsius. Around the higher temperature enzyme denaturation will decrease the reaction rate significantly. BACKGROUND INFORMATION Enzymes such as Catalase are protein molecules which are found in living cells. They are used to speed up specific reactions in the cells. They are all
Factors that affect the respiration of immobilised yeast.
Felix Simpeh Biology Coursework Factors that affect the respiration of immobilised yeast Date Completed: Thursday, 20 March 2003 To start off this experiment I feel that it is suitable to explain the main facts of this study. Below is a section explaining respiration and immobilised yeast in detail. Like all living organisms, yeast has to make energy, stored as ATP to carry out all cellular functions. To do this they can respire aerobically when there is plenty of oxygen, or anaerobically where oxygen is short, by this, they are called partial anaerobes. This produces less energy, but keeps the yeast alive. Pyruvic acid has to be broken down in respiration when formed by breaking down of glucose molecules, this can't be done in the same way as it is aerobically when respiring anaerobically which is how the carbon dioxide and ethanol is formed through the zymase. Here is the equation for the aerobic respiration: - Glucose + oxygen => energy + carbon-dioxide + ethanol Yeast can also respire without oxygen but less energy will be released. Respiration without oxygen is known as anaerobic respiration. When yeast respires anaerobically it produces alcohol. The reaction has the following equation: - Glucose => energy + alcohol + carbon-dioxide Cells, such as yeast are often used in industrial processes. At the end of the process the yeast is often mixed up with the
The Structure and function oflipids
The Structure and function of lipids Lipids are triglycerides, phospholipids and other related compounds. They contain Carbon, hydrogen and Oxygen, but have a higher ratio of hydrogen and oxygen than carbohydrates. And Lipids are more reduced than carbohydrates and are more readily oxidised when they are respired, and they therefore liberate twice as much energy per gram as carbohydrates and proteins. Lipids produce a lot of metabolic water when respiring and is useful to camels! Lipids are non-polar compounds and therefore do not dissolve in polar solvents, but they do dissolve in non-polar solvents. The triglycerides molecules are the biggest group of lipids and the energy store is found under the skin in adipose tissue, they consist of three fatty acid molecules joined by ester bonds (which are formed by condensation) to a glycerol molecule. They are the biggest group of lipids and the energy store is found under the skin in adipose tissue. Fatty acids with double bonds in the hydrocarbon chain are unsaturated; others are saturated fatty acids. The phospholipid molecules have two fatty acid molecules and a phosphate group joined to glycerol. The molecules are polar and have polar heads and form bilayers in aqueous systems. Lipids have many functions including insulation as they have subcutaneous fat, which is a good insulator, this is used by aquatic mammals, like the
Darwin's Finches
The Galapagos Islands is home to 13 species of finch, belonging to 4 genera. These finches all evolved from a single species similar to the Blue-Black Grassquit Finch Volatina Jacarina commonly found along the Pacific Coast of South America. Once in the Galapagos Islands the finches adapted to their habitat and the size and shape of their bills reflect their specializations. Vegetarian Finch and Ground Finch all have crushing bills while Tree Finch have a grasping bill and Cactus Finch, Warbler Finch and Woodpecker Finch have probing bills. All of Darwin's Finches are sparrow sized and similar in appearance with gray, brown, black or olive feathers. They have short rounded wings and a rounded tail that often appears cocked to one side. Most male finches mature to a solid black colour, while the females mature to a drab greyish colour. Exceptions are made for the Vegetarian and Tree Finches the males never become completely black rather they have a black head, neck and upper breast. Warbler, Woodpecker and Mangrove Finches have more of an olive colour. The finch vary by what they eat some eating seeds and others insects. The Ground Finches eat ticks they remove with their crushing beaks from Tortoises, Land Iguanas and Marine Iguanas and kick eggs into rocks to feed upon their contents. On Isla Wolf the Sharp Beaked Ground Finch is known as the "Vampire Finch" as it jumps on
Retroviruses & HIV
Retroviruses are a specialised type of virus, characterised by a unique mode of replication within the cells of their hosts. They contain a core of the nucleic acid RNA instead of the usual DNA. Unlike other RNA viruses, retroviruses replicate as DNA rather than RNA genomes inside their hosts by means of the enzyme, reverse transcriptase. Human Immunodeficiency Virus (HIV) is a retrovirus and upon infection, results in Acquired Immune Deficiency Syndrome (AIDS). When HIV infects a cell, it injects its RNA into the cytoplasm of that cell along with the reverse transcriptase enzyme. The cDNA produced from the RNA template contains the genetic instructions which allows infection of the host cell to proceed. In order to inject its genetic information into the host cell, the HIV must bind its envelope glycoprotein gp120 to molecules on the surface of the cell. Only cells that carry the appropriate molecules are susceptible to infection by HIV. Scientists have found that a molecule called CD4, which is found particularly on certain T-lymphocytes was the pirmary binding site but other co-receptors have since been discovered. Fusion of the virus with the cell membrane permits the viral nucleiod to enter the cell. The human immunodeficiency virus attaches to the CD4 protein on the surface of a T-lymphocyte, and the viral envelope fuses with the cell membrane. This fusion
Factors That Affect The Rate Of An Enzyme Reaction.
Factors That Affect The Rate Of An Enzyme Reaction. Introduction I am going to carry out an experiment to find out what affects the reaction of an enzyme. The enzyme that I am using is catalase from a piece of liver, and I will be reacting it with hydrogen peroxide. This reaction is extremely important, as hydrogen peroxide (which is extremely dangerous) is turned into water and oxygen through decomposion and sped up due to the catalase which acts as a catalyst. the equation for this reaction is: hydrogen peroxide oxygen + water 2H2O2 O2 + 2H2O An enzyme is the name of a protein that speeds up reactions. They are also known as catalysts. The enzyme I’m using, catalase, is found in the cells of all living things. Catalase helps speed up the breakdown on hydrogen peroxide into water. There are three main types of enzyme. They are oxidising, reducing and hydrolytic. Catalase is a hydrolytic enzyme, meaning that it breaks down a substance into simpler compounds, which in this case is hydrogen peroxide into oxygen and water. Variables There are a few different variables that could affect the rate of an enzyme reaction. They are: * Amount of liver used * Temperature of the reaction * Concentration of Hydrogen Peroxide * Surface area of the liver I have chosen to change the amount of liver used as my variable. This is because it is quite
