The investigation is aiming to look at transpiration.
NAME: AMAKA ARARAUME GROUP: B SUBJECT: BIOLOGY TITLE: TRANSPIRATION DATE: 25/10/03 AIM The investigation is aiming to look at transpiration. A range of different conditions will be used to determine the rate of transpiration in different plants {xerophytes and mesophytes}. I will also be comparing the rate of transpiration in xerophytes and mesophytes. PREDICTION The rate of transpiration in mesophyte will be higher than that in xerophytes. This is simply because: Xerophytes are plants that live in places where water is short of supply e.g. the desert. Here the rate of transpiration may exceed the rate of transpiration may exceed the rate of water uptake from the soil. These plants have control over the volume of water that they absorb, and hence their water balance depends on their ability to limit water loss. Any feature that significantly reduces the evaporation of water from aerial parts of the flowering plants, can be considered to a xeromorphic adaptations. Plants with these adaptations can be called xerophytes. They show the following adaptations: {a} roots are well developed: they grow down to the depth of the ground if necessary and branch extensively in order to absorb water from as large an area aw possible. {b} the presence of epidermal hairs: these trap humid hair thereby reducing the water potential gradient and hence the rate of transpiration. {c}
catalase and hydrgen peroxide
CATALASE AND HYDROGEN PEROXIDE Introduction My coursework is on catalase activity. This is done using hydrogen peroxide and two independent variables of my choice. I carried out a preliminary experiment so that I got a basic idea of what I was doing and what to expect. The aim of this experiment was to look at catalase activity and how time affects it. Preliminary Experiment This experiment was the first one which I carried out. From this I learnt about the reactions between catalase and hydrogen peroxide. For this experiment the apparatus which I used is as follows: * Tile - to cut potato and other substances on. * Knife - to cut substances with. * Side Arm Tube - for substances and hydrogen peroxide to go in and a reaction to take place. * Rubber Arming - to connect the measuring cylinder with the side arm tube, to allow oxygen bubbles to flow through. * Bee Hive Shelf - to feed rubber arming through and support measuring cylinder. * Stop Clock - to count the number of minutes when carrying out the experiment. * Measuring Cylinder - where the oxygen is released. * Potato - for the reaction to occur. * 15cm³ Hydrogen Peroxide - for the reaction to occur. * Half Tank of Water - to help the reaction occur and produce oxygen. I set up the apparatus; I cut the potato into small pieces that would fit into the side arm tube, so that the reaction would not be too
Water and Marine Resources
Water and Marine Resources Introduction Water is one of the most important inorganic compounds in the world, playing vital physical, biological and chemical roles. For many governments the main challenge for the twenty-first century is how to ensure a reliable supply of good- quality, fresh water. This chapter is divided into two sections. The first concentrates on fresh water, whilst the second deals with salt water. Such a division is convenient from a human viewpoint but is of no relevance from an environmental viewpoint because the different states in which water exists are not restricted by salt and fresh water definitions. Water location and water disputes Vast areas of the world are already deficient in a supply of freshwater. These water deficiencies are often the result of poor management of the water resource, rather than an overall lack of precipitation. Disputes over water extraction from rivers have grown in number and severity in recent years. As the shortfall between demand and supply of water increases so international disputes over water availability are also set to grow. The World Resources Institute in 1996 estimated that 40% of the world's population gets its water from just 214 major river catchment zones. Of these, 148 are shared between two countries and a further 50 are shared between three or more countries. The Nile basin illustrates some of
Three separate experiments which are to be carried out to investigate a plant's unique property of transpiration.
BIOLOGY COURSEWORK - TRANSPIRATION IN PLANTS AIM: I have three separate experiments which are to be carried out to investigate a plant's unique property of transpiration. I will carry out the following three experiments to investigate transpiration: * The use of a potometer to investigate the rate of transpiration and the relationship between leaf surface area and water uptake. This experiment will take place over a double lesson. * Using a microscope to find the number of stomata on one of the Laurel leaves and then using the results to calculate the number of stomata on each leaf. * My third experiment to prove that the substance being lost from the leaves is water by using cobalt chloride paper. SCIENTIFIC BACKGROUND: Overall plant structure: The following diagram shows the overall structure of a plant, and identifies the uses of each different part of the plant: As you can see by looking at the diagram to the left, there are several key parts to the plant, all of which have a major part in the transport of water in plants (i.e. transpiration). The roots can be seen towards the bottom of the diagram. The roots suck up the water from the soil which the plant is in. They do this because of the added effects of transpiration and capillary rise. Capillary rise is where a liquid climbs up a very narrow tube, defying gravity almost. As the water evaporates from the
Should the cloning of humans be allowed?
Should human cloning be allowed? By Gabriella Azanu 10A Table of Contents Introduction 3 What is cloning? 3b Recombinant DNA Technology 3c Therapeutic Cloning 4b Reproductive Cloning 5a Arguments for Cloning 6 Infertility and Premature Death 7a No Risk of Genetic Disease 7b Cloning to Cure Disease? 8a Counter Arguments 8b Arguments against Cloning 9 Large Offspring Syndrome 9b Reliability of Cloning 9c Other Problems with Cloning 10a Genetic Diversity 11a Counter Arguments 11b Conclusion 12 Bibliography 14 Arguments against Cloning 16 Introduction Over the past recent years, the issue of cloning organisms has become one of the most debated subjects in science and the media. Cloning is a relatively new science which only really began with the experimental cloning of the 1950's. The first clone was created in 1952, when researchers created a cloned tadpole by transplanting the nucleus from a frog embryo into a frog's egg. However, this experiment wasn't actually meant to clone frogs but to investigate totipotent cells, cells which are able to develop into any cell type and is the foundation for multi-cellular (many celled) organisms 1. In spite of this, the scientific breakthrough came when Dolly the sheep became the first mammal to be cloned using adult cells from the udders of a female adult sheep.2 More recently, cloning has had
Investigating the cellular water potential of potato cells.
Investigating the cellular water potential of potato cells. Aim: - to determine the water potential of potato cells by using different concentrations of sucrose solution. Introduction:- Water potential is the tendency of water molecules to move from one place to another, water potential can also be represented by the Greek letter psi, ?. The water potential for pure water is 0. This is because there is no tendency of the water molecules to move. The movement of water molecules almost always tends to be from a region of high water potential to a region of lower water potential. This is down the water potential gradient. Water potential can be affected by various factors, such as the amount of solute that is in the solution and the pressure that is being exerted. Solute potential (?s) is the amount by which the solute molecules lower the water potential of a solution. As the solute decreases the water potential of a solution, the water potential becomes more negative as more solute is added. Fig. 1 Diagram of solutions with different water potentials. In the diagram, side A has a less negative and so a higher water potential (it is closer to 0, than side B). This is as side B has a greater amount of solute molecules in it than side A, which means that the water molecules in side A have a greater tendency to move. Side B has the greater solute lower (more negative)
An investigation into the effect of a germination inhibitor on the germination of seeds.
GERMINATION INHIBITORS An investigation into the effect of a germination inhibitor on the germination of seeds. INTRODUCTION The necessary conditions For a seed to germinate there are specific conditions different seeds need. In this experiment, cress seeds are to be used. Going through the basics first though, for a seed to successfully germinate there needs to be: o An adequate supply of water o A suitable temperature o An appropriate partial pressure of oxygen o A suitable supply of light Water uptake is a crucial part of the necessary conditions because germination can only commence after the uptake of water by the seed. Water absorption is imbibition. The optimum temperature for germination is the optimum for the enzymes involved in mobilisation of food reserves, provided that other factors are not limiting. This temperature varies from species to species (i.e. 1 - 45°C). Respiration makes available the energy for metabolism and growth. Germinating seeds respire very rapidly, and require oxygen for aerobic respiration. Seeds will not germinate in the total absence of oxygen. Diffusion of oxygen through the testa may be slow, however, and in the early stages of germination seeds may rely on some anaerobic respiration, at least until the testa has ruptured. So this explains why water, oxygen and a suitable temperature are needed for germination, therefore
The effect of hydrogen peroxide on catalase if you change the temperature.
The effect of hydrogen peroxide on catalase if you change the temperature AIM Effect of temperature of the action of the Enzyme Catalase. PLANNING Background Knowledge An enzyme is a biological catalyst, it alter the rate of reaction without being changed itself. Enzymes are proteins; they have a very precise three-dimensional shape, which forms a one specific active site on the enzyme. Each enzyme can only convert one kind of substrate molecule in to one kind of product molecule. These are specific. What affects Enzymes? · Temperature- Enzymes stop working if the temperature rises above 40ºC. Increasing the temperature alters the 3D shape and so the enzyme can no longer fit the substrate. · pH- They work best in neutral conditions neither acidic nor alkaline. What affect does catalase have? Catalase is a very fast reacting enzyme, it is found in many living cells, it breaks down hydrogen peroxide to water and oxygen. In fact one molecule of it can deal with six million molecules of hydrogen peroxide in 1 minute. Hydrogen peroxide is toxic so needs to be changed into harmless substances. Catalase Hydrogen peroxide water + oxygen 2H2O2 2H2O + O2 References to practicals referring to enzymes · Biology for You Pg 30 - Experiment 3.1 From looking at this I found out that catalase reacts with hydrogen peroxide to give out water and oxygen. Oxygen bubbles produce
An Investigation into the effect of surface area on the activity of catalase in potato.
An Investigation into the effect of surface area on the activity of catalase in potato An experiment to find out how the application of different surface areas of the same sized potato chip, effects the reaction rate of catalase in the potato chip, whilst submerged in hydrogen peroxide at a controlled temperature and pH level. Introduction: Enzymes are large proteins and catalysts and increase the speed of a chemical reaction without undergoing any permanent chemical change. They are neither used up in the reaction nor do they appear as reaction products. 2 Enzymes, such as Catalase, are globular protein molecules which are found in living cells. 3 In their globular structure, one or more polypeptide chains twist and fold, bringing together a small number of amino acids to form the active site, or the location on the enzyme where the substrate binds and the reaction takes place. Enzyme and substrate fail to bind if their shapes do not match exactly. This ensures that the enzyme does not participate in the wrong reaction, as they are all very specific, as each enzyme just performs one particular reaction. 4 Catalase is an enzyme found in food such as potato and liver. It is used for removing Hydrogen Peroxide from the cells. Hydrogen Peroxide is the poisonous by-product of the affects of metabolism. Catalase speeds up the decomposition of Hydrogen Peroxide into the two
To investigate how varying the concentration of sucrose solutions affects the rate of osmosis between the solution and potato cylinders immersed in it.
Osmosis in potato cells Section 1: Planning Aim: To investigate how varying the concentration of sucrose solutions affects the rate of osmosis between the solution and potato cylinders immersed in it. Hypothesis: A substance, when dissolved in water, has a natural desire to dilute itself by bonding with surrounding water molecules. When a semi permeable membrane, such as a cell membrane separates two solutions, pure water flows from the weaker solution to dilute the stronger one until they are both the same strength. The term used to describe the flow of water through a semi permeable membrane separating two solutions of different concentrations is osmosis. In other words, osmosis is the process in which water passes in and out of plant cells thus controlling their turgidity. It is in fact the diffusion of water from places of high water concentration to places of low water concentration and can take place only across a selectively permeable membrane - such as the cell membrane. The cell membrane allows small molecules such as those of water to diffuse through it. However, larger molecules such as those of sucrose can not pass through its pores. This movement of water will continue until equilibrium is attained and the concentration is equal on both sides of the cell membrane. An example of a region with high water concentration is distilled water or very dilute
