The Role of Carbohydrates in Living Organisms
The Role of Carbohydrates in Living Organisms Carbohydrates are composed of the elements carbon, hydrogen, and oxygen. The general formula is Cx(H2O)y. There are many different types of carbohydrates present in living organisms, each playing an important role in maintaining life of organisms. Monosaccharides are a group of carbohydrates, which include simple sugars such as glucose, fructose and galactose. Monosaccharides are classified according to the number of carbon atoms they possess. Trioses such as glyceraldehyde, and dihydroxyacetone contain three carbon atoms. The phosphorylated form of glyceraldehyde is the first formed sugar in photosynthesis, and may (like dihydroxyacetone) be used as respiratory substrate, or is converted to starch for storage. Both of these trioses are intermediates in glycolysis, where glucose is broken down by enzymes into pyruvic and lactic acid. Pentoses such as ribose an ribulose possess five carbon atoms. Ribose or deoxyribose make up part of nucleotides and as such give structural support to nucleic acids RNA and DNA. Ribose is a constituent of hydrogen carriers such as NAD, NADP and FAD. Further more it is involved in the synthesis of coenzymes and ATP. The third type of monosaccharides is hexoses like glucose and fructose, which possess six carbon atoms. Glucose has a number of significant functions in both plants and animals. Most
Investigating and testing for reducing and non-reducing sugars
Biology - Experiment write up Investigating and testing for reducing and non-reducing sugars Aim: To use techniques to test a selection of known and unknown substances, to determine whether or not they are a reducing, non-reducing sugar or neither. Prediction: In the first part of the experiment (simple Benedict's test), I predict that out of the three solution samples; glucose, sucrose and sample X, only glucose will change from the blue colour. I do not know what the substance in sample X is and therefore cannot comment on the outcome. However in my opinion sucrose will not change colour during this part of the experiment. In the second part of the experiment, when using acid to break any glycosidic bonds and sodium hydrogen carbonate to neutralise the solution, I predict that sucrose will change colour. In my opinion the part of the experiment will make no difference to the glucose and therefore the outcome to this second part will be the same as part one of the experiment. Apparatus List: * Beaker * Test tube rack * Test tubes * Samples of sugar solutions * Syringe * Pipette * Benedict's solution * Hot water available * Hydrochloric acid, HCL * Sodium hydrogen carbonate, NaHCO3 * Universal indicator paper Theory: Benedict's solution is often used as a general test for detecting reducing sugars. If the saccharide is a reducing sugar, it will reduce the
The effect of temperature on the permeability of beetroot membrane
The effect of temperature on the permeability of beetroot membrane A1: Develop a hypothesis * What do you understand to be the nature of the problem? Beetroot contains pigments called betalain pigments which give them their distinctive red colour. This pigment is found in the vacuole of the beetroot and in order to release it the vacuole must be broken down. In order to break the vacuole down I am going to use heat shock. When treated with heat the phospholipid bilayer becomes damaged and turns into fluid. When treated with heat the beetroot membrane will break down releasing the red betalain pigments. As I use different levels of heat shock the amount of betalain released should be relative to the increase in temperature. Therefore in theory the higher the temperature the more betalain pigment released so the redder the sample. * Outline the biological basis of the problem As I am using heat shock the cell membrane will become damaged. When cell membranes become damaged they release the contents of the cell in this case betalain. The cell membrane of beetroot is composed of a phospholipid bilayer. This bilayer is made up of hydrophyllic heads and hydrophobic tails, so when these become damaged by heat they can no longer restrict what enters and leaves the cell. Within the beetroot there are a number or vacuoles containing the red pigment betalain, so when the
As protein denaturation can be cause by several factors such as temperature, pH, salt concentration. In this experiment, we are examining how these factors affect the denaturation of protein.
By y.c.pong Introduction: When you heat an egg, the egg white clump together and turned white. It is because the protein in egg white undergoes denaturation, the cross linkage(the hydrogen bonds, ionic bonds and disulphride bonds) which maintain the protein shape destructed, so protein lose its tertiary conformation. This denaturing process is very important, because before protein can be used in digestion they must be unfolded. Part A: denaturation of egg white Aim: To examine the factors on the effect of denaturation of egg white. Principle: As protein denaturation can be cause by several factors such as temperature, pH, salt concentration. In this experiment, we are examining how these factors affect the denaturation of protein. We use egg white, which is actually a solution of protein in water in this experiment. After the egg white had been dilute, the egg white solution can be put in 60°C and 80°C water bath to test for how temperature affects denaturation. It can be record by the time need for the first change of appearance. To find out how pH of affect denaturation, we can add dropwise the actetic acid to the egg white solution. Beside, the NaCl can also be add dropwise to egg white, to test for how salt concentration cause denaturation. Count the number of drop of solution added for an appearance change to occur. Observation: (1) 60 °C water bath
Investigate the effect of temperature on dehydrogenase activity in yeast. At which temperature is tetrazolium chloride (TTC) discoloured most rapidly?
Investigate the effect of temperature on dehydrogenase activity in yeast. At which temperature is tetrazolium chloride (TTC) discoloured most rapidly? Introduction Enzymes are composed of many specialised organic substances, such as polymers of amino acids, which act as catalysts to regulate the speed of the many chemical reactions involved in the metabolism of living organisms. Individual enzymes are naming by adding -ase to the name of the substrate with which they react. There are many types of enzymes such as... hydrolytic, oxidising, and reducing. * Hydrolytic... speed up reactions in which a substance is broken into simpler compounds through reaction with water molecules. * Oxidases... these are oxidising enzymes that speed oxidation reactions. * Reductases... reducing enzymes that accelerate reduction reactions. "Enzymes are highly specific in their actions. Each enzyme catalyses either a single chemical reaction or a group of closely related reactions" Enzymes operate by attaching themselves to their substrate molecule at the active site. The theory that enzymes and substrates bind is called the 'lock and key' hypothesis. As the enzyme (A) and the substrate (B) form a complex (AB), the substrate is raised in energy to a transition state, and then breaks down to products (C) plus an unchanged enzyme (E)... A + B --> AB --> C + E In this experiment the only
The Role of the Respiratory and Circulatory Systems in the Provision of Oxygen and the Removal of Carbon Dioxide from the Body
The Role of the Respiratory and Circulatory Systems in the Provision of Oxygen and the Removal of Carbon Dioxide from the Body The purpose of breathing is to supply a continuous supply of fresh oxygen into the body and to remove carbon dioxide. Oxygen is essential for cells to function. Blood acts as the transport mechanism for gases to move between the lungs and tissues by passive diffusion. These gases will diffuse down their pressure gradient from areas of high pressure to areas of lower pressure. Atmospheric air contains approximately 79% nitrogen and 21% oxygen plus negligible amounts of water vapour, carbon dioxide and pollutants (Boyle & Senior, 2008). Air needs to enter and leave the body in a continuous, rhythmic pattern to sustain the body. Cardiac muscles rhythmically contract and relax to empty and refill the heart; respiratory muscles also act in a rhythmic pattern to fill and empty the lungs with air. These two actions are performed involuntary - the heart by means of a pacemaker and the respiratory muscles at a brainstem level. Specialised neurones called dorsal medullary respiratory neurones produce a cycle of activity that occurs every few seconds to establish the basic routine of respiration When air is breathed in, the external intercoastal muscles, of which there are eleven on each side of the body, contract and pull the ribcage upwards and outwards
The Effect of Substrate Concentration on Enzyme Action.
The Effect of Substrate Concentration on Enzyme Action Aim The aim of this investigation is to determine the effect of substrate concentration on enzyme action. The reaction analysed was that between the substrate hydrogen peroxide and the enzyme catalase found in yeast to break down the hydrogen peroxide. Background Catalase behaves as a catalyst for the conversion of hydrogen peroxide into water and oxygen. Catalase is an example of a particularly efficient enzyme. Catalase has one of the highest turnover numbers for all known enzymes (40,000,000 molecules/second). This high rate shows an importance for the enzymes capability for detoxifying hydrogen peroxide and preventing the formation of carbon dioxide bubbles in the blood and this is why this enzyme is formed in the body. Catalase is made in the liver when found in the body. But for the purpose of this experiment yeast shall be used as the form of catalase. (1) Hydrogen peroxide is a by-product of respiration; it also simplifies the whole process of growing fungi and in the treatment of contaminated waters. Since it was first commercialised in the 1800's, H2O2 production has now grown to over a billion pounds per year (as 100%). In addition to pollution control, H2O2 is used to bleach textiles and paper products, and to manufacture or process foods, minerals, petrochemicals, and consumer products (detergents). Its
Homeostatic Control of Blood Glucose Levels
Adnan Undre Homeostatic Control of Blood Glucose Levels Glucose is an essential substance in the body as it the primary source of energy for all biological functions and is indeed the only form of energy which can be used by the brain and central nervous system. The ideal level of blood glucose is 80 - 90mg of glucose per 100mls of blood. However this level is not static - it oscillates due to changes in the body which are brought about by actions such as eating a meal, exercising, or not eating for long periods. If blood glucose levels drop or rise dramatically there may be serious consequences such as hypo- or hyperglycaemia which can both cause death. Thus it is necessary for blood glucose levels to be regulated and this is achieved through homeostasis. To work effectively homeostasis requires an effective receptor to detect variations from the norm and a negative feedback system where antagonistic processes work to redress any variations as they occur. By examining the mechanisms of the homeostatic control of blood glucose levels it should be possible to explore the consequences of a breakdown of this part of the endocrine system. Essentially, blood glucose levels are controlled by the pancreas. It is in this organ that areas of cells called the Islets of Langerhans exist, which consist of alpha cells and beta cells. These cells monitor blood glucose and secrete the
Comparison of Transport System in Amphibian and Mammalian models
Practical 5 Comparison of Transport System in Amphibian and Mammalian models .0 Introduction Frogs belong to a group of animals called Amphibia that tend to almost always reside in confined habitats near water; making them both terrestrial and water-living animals. They tend to inhibit moist, damp conditions such as swamps and marshes. Frogs have powerful hind limbs adapted for swimming and leaping as their method of locomotion. The webs on the hind feet provide a large surface area for pushing against the water surface. Their eyes have a protective lid and can be withdrawn into the skull while the eardrums are located behind and below the eyes. Frogs have a loose-fitting, thin, moist skin which is supplied with a network of blood vessels. The skin is used for respiration and oxygen is absorbed through its surface and into the blood. The frog's nostrils are specialized to allow respiration while submerged underwater. There are valves that prevent water from entering their nasal cavities. Rats belong to a group of animals called Mammalia that are solely terrestrial. Round circular ears are located on both anterior sides of the rat's head. They have small eyes and the mouth is located below the nose. The rats have a touch sensor system that is known as the whiskers on its nasal region called the vibrissa. As for the neck and body, a rat has a short neck with its body
Core practical(Why does the colour leak out of cooked beetroot?)
Core Practical Why does the colour leak out of cooked beetroot? Introduction:- Beetroot contains red pigment called betalain, located within the cell vacuole. Normally the pigment cannot pass through membranes but they leak out when the beetroot cooked because the cell membrane begins to breakdown. Hypothesis:- My hypothesis is that when temperature increases the proteins in the membrane will be denatured and the pigment will leak out of the cell membranes and will colour the water in the test tubes. Method:- Apparatus:- a thin cylinder of beetroot tissues, nine test tubes, beaker ,Bunsen burner, water, thermometer, colorimeter. Variables:- * Independent: Time, temperature * Dependant: Intensity of red in water Procedure * We were provided with thin cylinders of beetroot tissue, which was washed in running water overnight. * We took nine test tubes and labelled them from A-I. And we placed 6 cm3 of water in each tube with the help of pipette. * We put nine cylinders of beet root tissues into a beaker of 150 cm3 of water. * We put a beaker on a Bunsen burner and took some water and heated the water and then put a thermometer in to the beaker. * We put beet root in to the hot water for two minutes and noted the temperature. * We transferred the beetroot to the test tube A
