To investigate the effect of temperature on the enzyme catalase.
Aim: To investigate the effect of temperature on the enzyme catalase. Prediction: Using my existing scientific knowledge, I predict that as I raise the temperature to 30, 35, and 40, this is where we will see the greatest reaction. I predict this because enzymes are designed to react best at the body temperatures of the animals to which they belong. For a mammal, this is around 35-36. Catalysts are used to speed up biochemical reactions in the body. An enzyme is a protein molecule that speeds up chemical reactions in all living things. Without enzymes, these reactions would occur too slowly or not at all, and no life would be possible. All living cells make enzymes, but enzymes are not alive. Enzyme molecules function by altering other molecules. Enzymes combine with the altered molecules to form a complex molecular structure in which chemical reactions take place. The enzyme, which remains unchanged, then separates from the product of the reaction. Therefore, an enzyme is a sort of biological catalyst. Those enzymes identified now number more than 700. Enzymes are classified into several broad categories, such as hydrolytic, oxidising, and reducing, depending on the type of reaction they control. Hydrolytic enzymes accelerate reactions in which a substance is broken down into simpler compounds through reaction with water molecules. Oxidising enzymes, known as oxidises,
To investigate the effect of temperature on the enzyme catalase.
To investigate the effect of temperature on the enzyme catalase Aim: To investigate the effect of temperature on the enzyme catalase Apparatus Celery extract (catalase) Labels 20 Volume hydrogen peroxide Distilled water 6 100cm beakers 20cm and 50 cm measuring cylinders Balance Stopwatch Trough Clamps & stand 50cm conical flask + bung + tubing + 3 way tap 0cm syringe Beehive shelf Gas syringe Goggles Water bath at 25 & 35°C 250cm beakers & thermometer for water bath Method .Weigh out 1 sample of celery extract of 10g in a conical flask. 2.Place in a water bath at 25°C. 3.Place about 20cm hydrogen peroxide solution in a container in the same water bath. 4.Leave for 10 min to equilibrate. 5.Set up the apparatus as follows: -Fill a trough with water -Fill a measuring cylinder with water and invert in the trough (ensure that no air bubbles are in the water) -Secure the cylinder with a clamp & stand -Position the bung and 3 ways tap to fit on a conical flask, ensure that this can be held in place with a clamp & stand -Put the end of the tubing in the measuring cylinder 6.Make sure that the tap is closed and fill a syringe with 10cm hydrogen peroxide from the water bath. 7.Take the first conical flask containing the celery extract; arrange the apparatus as above and empty the syringe into the flask closing the 3-way tap start the stopwatch.
To investigate the effect of temperature on the rate of reaction
Title: To investigate the effect of temperature on the rate of reaction. Objective: To study on how temperature relates to the rate of reaction. Procedures: . 5cm3 of the hydrochloric acid is added to a boiling tube. 2. 20cm3 of the sodium thiosulphate solution is added to another boiling tube. 3. Draw a large cross on a piece of paper* and a beaker is placed over it. A heat-resistant mat is put under the paper. (*In the experiment, the heat-resistant mat is directly drawn with a cross, so that we did not need to draw it on a sheet of paper.) 4. Another beaker which contains water is prepared. 5. The two boiling tubes are put inside the beaker for a hot water bath, both with a thermometer*. In the first time of the experiment, this step is skipped because the experiment is done in room temperature, but a thermometer is still put into a boiling tube to measure the temperature. (*In the experiment, we have only got one thermometer so we measured the temperature of the water bath.) 6. After both of the solutions reach the suitable temperature, they are poured into the beaker which is prepared in step 3. Start the stop watch simultaneously. 7. The solution is stirred*. A person watches the cross vertically during the reaction. (*In the experiment, we did not stir the solution.) 8. Stop the stop-watch when the cross on the paper just 'disappeared'. 9. Record the time
Transport across plasma membranes.
Transport across plasma membranes The cell surface membrane is approximately 7.5mm thick and is a bi-molecular phospholipid bilayer with inwardly directed hydrophobic (substances which repel water molecules) tails. It is also a fluid structure. A partially permeable membrane is one which allows some substances through but not others. There are a number of different ways in which substances are transported across plasma membranes. The first being diffusion, which occurs across the cell surface membrane. This is a passive process (requires no energy) by which substances move from a region of high concentration to a region of low concentration, of the same substance. The rate of diffusion depends on a number of factors: * The concentration gradient * The distance between the areas * The size of the molecules that are diffusing Particles of gas or solute can also diffuse through a membrane, as long as the membrane has pores that are larger than the particles. Every substance diffuses down its own concentration gradient. The concentration gradient of one substance has no effect on the concentration gradient of another substance. An example of diffusion is a tea bag in water - the flavour and colour from the tea inside the bag diffuse through the water. Another example is oxygen diffusing into a red blood cell in the body. Another process by which substances are transported
The Uses of Enzymes In Industry, Medicine and Analytical and Diagnostic Processes.
The Uses of Enzymes In Industry, Medicine and Analytical and Diagnostic Processes Enzymes are very precise protein molecules with a high specificity which are used to catalyse chemical reactions by lowering the activation energy required for the reaction to take place. It is these properties of being able to break down substances easily and bind specifically to certain chemicals that make enzymes very useful in many industries and practices throughout the world. In addition to this enzymes are not used up in experiments so products of processes are not contaminated with enzyme which could be a problem. This essay explains 3 uses of enzymes, in industry and food, diagnosing and analysing, and treating disease, explaining the function and advantages of enzyme use in each example. In industry enzymes are used for many processes such as brewing beer, baking bread, using pectinase to increase juice in fruit juice drinks and protease enzymes in washing detergents. Another example of the use of enzymes in industry is animal feeding. Many monogastric species such as poultry are fed food with enzymes added which break down substances in the food which the species body cannot digest. Many foodstuffs for farm animals such as wheat, rye, barley and oats contain non-starch polysaccharides (NSPs) which are an example of ANFs (anti-nutritional factors). They cannot be broken down by the
The ways in which organisms use ATP
The ways in which organisms use ATP The major energy currency molecule of the cell, ATP, is evaluated in the context of creationism. This complex molecule is critical for all life from the simplest to the most complex. It is only one of millions of enormously intricate nanomachines that needs to have been designed in order for life to exist on earth. This molecule is an excellent example of irreducible complexity because it is necessary in its entirety in order for even the simplest form of life to survive. The ATP is used for many cell functions including transport work moving substances across cell membranes. It is also used for mechanical work, supplying the energy needed for muscle contraction. It supplies energy not only to heart muscle (for blood circulation) and skeletal muscle (such as for gross body movement), but also to the chromosomes and flagella to enable them to carry out their many functions. A major role of ATP is in chemical work, supplying the needed energy to synthesize the multi-thousands of types of macromolecules that the cell needs to exist. ATP is also used as an on-off switch both to control chemical reactions and to send messages. The shape of the protein chains that produce the building blocks and other structures used in life is mostly determined by weak chemical bonds that are easily broken and remade. These chains can shorten, lengthen, and
The structure and function of carbohydrates.
The structure and function of carbohydrates Carbohydrates are named for their characteristic content of carbon, hydrogen, and oxygen (CH2O). Carbohydrate molecules are categorized by the number of carbons present in the molecule. Short chains containing from three to seven carbons form the monosaccharides, which are the most basic sugars. Monosaccharides with five or more carbons can form a ring as well as a linear configuration. The rings form through a reaction between two functional groups in the same molecule. Each carbon atom in the chain, except one, carries an -OH group. The remaining carbon carries a -C=O (carbonyl) group. In monosaccharides hydrogen atoms occupy all other available binding sites of carbon. Glucose, the most common monosaccharide has six carbons per molecule, which is called a hexose. Carbohydrates also have 2:1 hydrogen to oxygen ratio. This aids in the condensation and hydrolysis reactions. A condensation reaction occurs when two monosaccharides join by the removal of water (H2O). During condensation synthesis one monosaccharide losses an OH and the other losses an H. As a result the two monosaccharides bond by forming maltose a disaccharide with a by-product of a free H2O molecule. When three or more monosaccharides or monomer are involved in a condensation synthesis a polymer or polysaccharide is formed with a by-product of water. Starch and
The theory of endosymbiosis
The theory of endosymbiosis (Endo Within, Symbiosis Living together! ) I am going to analyze the theory of endosymbiosis over the next few pages. I am going to give arguments for and against so I can make a reliable conclusion. First of all I am going to give some information about the theory of endosymbiosis. According to the theory of endosymbiosis, billions of years ago mitochondria and chloroplasts were free-living bacteria (prokaryotes) which somehow became part of an early cell. The primitive Earth did not have oxygen in its atmosphere so these early cells must have been able to survive with out oxygen. However, oxygen gradually oxygen built up in the atmosphere and it is possible that some bacteria evolved which were able to use oxygen for respiration (aerobic bacteria). According to the theory, an aerobic bacterium became engulfed by an anarobic amoeba-like bacterium, and the amoeba-like bacterium navigated through the newly oxygen rich waters in search of food. In support of this theory of endosymbiosis, scientists have shown that oxygen began to accumulate between the first fossil records of prokaryotes and the later fossil records of eukaryotes. Anaerobic amoeba-like Anerobic bacterium Aerobic bacterium bacterium. engulfs aerobic bacterium. becomes symbiotic inside
What are 'Enzymes'?
Introduction Enzymes are biological catalysts that carry out thousands of chemical reactions that occur in living cells. They are a class of proteins that have a unique three dimensional structure that allows it to bind with a specific substrate to facilitate a reaction. Many biological reactions will not occur spontaneously in the cell; there is simply not enough energy for the reaction to take place. Enzymes make these reactions possible by lowering the reaction's activation energy. Each cell has tens of thousands of different enzymes that collectively allow both the break down and synthesis of molecules to drive all cellular processes. This investigation will explore the effect of pH on the three-dimensional structure of a protein. Much of the three-dimensional structure of an enzyme is held together by weak interactions including H-bonds, ionic bonds, and hydrophobic interactions. These interactions can be easily disrupted by changes in temperature, salt concentration, and pH. pH levels out of the normal intracellular range would denature enzymes, slowing the enzyme's reaction rates. Hydrogen peroxide (H2O2) is a toxic chemical that is continually being formed as By product of reactions in peroxisomes of living cells. Since it is poisonous, the cells must either get rid of it or change it to something nonpoisonous. If they cannot do this, the cell may die;
What are enzymes?
Enzymes What are enzymes? Enzymes are biological catalysts they alter the rate of reaction without it self being used up or changed during the reaction. Without enzymes the reactions that take place in an organism would be too slow for life to continue. Enzymes are proteins and how an enzyme functions is determined by its three dimensional structure. An enzyme has: > Three dimensional shape > Area on its surface called Active site The substance that the enzyme helps to react is called the substrate. Substrate has complementary to the active site and the substrate fits into the active site. The active site of each of each different enzyme has its own particular three-dimensional shape so only a substrate with a complementary shape will fit it. Most enzymes catalyse speed up only one reaction or one group of reactions. Below shows the break down Maltose to Glucose Maltase + Maltose = Maltase + Glucose In the above reaction Maltose is the substrate and Maltase is the enzyme and the product formed is Glucose. Maltase will only speed up the break down of Maltose to Glucose it does not act on ant other substrate. How they work? Like all other particles in the cell Enzyme molecules are constantly moving about colliding with other molecules. When an enzyme molecule collides with its substrate molecule the substrate binds to the enzymes active site. The substrate when
