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Essays in Molecules & Cells category
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The human body - Action and control
... and free from disease. Plants make their own food using energy from the sunlight. Animals eat plants or other animals Food is broken down from big, insoluble molecules to smaller, soluble molecules during the process of digestion. The smaller molecules (nutrients) ...
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The Human Body - Action and Control - The Investigation and the Theory Behind it
... fit into the enzymes active site. The reaction then takes place and the products leave the enzyme. The product is the chemical that is made. The substrate molecules fit precisely into the enzyme molecules. This theory is referred to ...
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The human digestive system.
... shape. since enzymes can only function if they have a particular shape, the type of substance they act on depends on which substance has a complementary shape to the enzyme. hence, a different enzyme is requires for each type of food ...
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The Human Embryonic Stem Cells and the Promise of Stem Cell Based Treatments.
... humans: embryonic stem (ES) cells and adult stem cells, which have different functions and characteristics. In late 1998, a group of scientists led by University of Wisconsin-Madison developmental biologist James Thomson became the first in the world to successfully isolate and ...
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The Human papilloma virus
... risk" HPV's are less common and it is said that there are only 13 types in existence. High risk HPV's are classed as carcinogenic as they cause mutations of the cells they infect. Source: NIH-Visuals Online# AV-8610-3067. Author: Laboratory of ...
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The Hydrolysis of Urea by Urease
... tube at the start. It was then left in a water bath at 30?C for one hour to give the substances time to react. We again measured the amount of gas in the tube with a ruler and recorded the ...
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The Immune system.
... by B cells, they circulate in the blood that attacks disease and causes organisms, T cells attack organisms head on, and these cells can memorize earlier infections and therefore can act fast to avoid further attacks. The defence of the ...
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The Importance of Biological Molecules.
... the name of a semi-permeable membrane. Thus the cell can alter the concentrations of certain molecules within itself as necessary. This makes the interaction of lipids and proteins within plasma membranes biologically important. "Lipids are crucial components of many signal transduction ...
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The importance of cell membranes.
... membrane are peripheral and integral proteins, glycoproteins, cholesterol and glycolipids. Glycoproteins are formed when carbohydrates are attached to the proteins in the membrane, and glycolipids form when the carbohydrates are attached to the phospholipids. The organisation of a phospholipid bilayer ...
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The importance of water in biological processes
... molecules will be attracted to each other. These forces are called hydrogen bonds which makes the properties of water very special. The hydrogen bonds mean that water is a good solvent, cohesive, habitat and temperature stabiliser It acts as a ...
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The Industrial Application of Enzymes.
... long before anybody knew of the existence of enzymes. One of the earliest references can be found in Homer's Greek poems dating from about 800 BC where he mentions the use of enzymes in the production of cheese. The starch ...
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THE INDUSTRIAL USES OF ENZYMES
... to get juice, then they are stored in containers containing yeast, which ferment the juice, and produce ethanol and carbon dioxide gas, then the wine is stored in containers to remove any impurities. This is for usually a month, and ...
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The investigation to find the effect of glucose concentration on fermentation of yeast.
... investigation such as temperature, the volume of yeast and the volume of glucose. To make a fair test I am going to keep this three factor constant, I will also leave the experiment undisrupted during the course of reprising, this ...
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The main aim of this experiment is to investigate how varying the concentration of an enzyme will affect the activity of the enzyme trypsin in milk.
... These reactions do not change the catalyst. So, even small amounts of an enzyme can do a big job. ii) Protein- Whose chemical; shape is special to the substance it works on. iii) Specific- Protein alone fits into the chemical shape ...
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The main objective in this experiment is to compare the growth kinetics and the level of ß-galactosidase induction in the presence of four different growth substrates; glucose, lactose, IPTG and water.
... energy in the production of unnecessary proteins. Most of these mechanisms take place at the transcriptional level where genes can turn on or off at different conditions. Gene regulation is the control of biological information encoded by the different control ...
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The Main Scientific Processes in Beer Making at Ridleys.
... the process malting must be completed to lead om to the brewing process. Brewing This serves to solubilise the starchy and proteinic matter in the malt. Three litres of water at 50°C per kilo of malt is put into a boiler equipped with ...
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The majority of the reactions that occur in living organisms are enzyme-controlled.
... ring of atoms) whereas trypsin only splits bonds after a basic or straight chain amino acid. This specificity leads to the lock and key hypothesis. However, it has been discovered that competitors for an active site (similar in shape to ...
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The Matrix Reloaded: Rewritten.
... complex computer system, and once more he found himself in his long leather jacket and mysterious Sunglasses, with a cell phone in his hand, only something wasn't right... He looked around. These weren't the New York streets. They weren't even streets ...
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The Movement of Substances Across Cell Membranes
... the nucleus have a double membrane. The outer membrane is fairly smooth. But the inner membrane forms folds called cristae. The cristae increase the inner membrane's surface area. It is on these cristae where ATP is produced, which is the ...
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The optimum temperature for the enzyme amylase.
... of reactions by giving the reacting particles a surface to stick to where they could bump into each other. This increases the number of collisions. Enzymes work under the process call Lock and Key Hypothesis. This is shown in the ...
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The Origin of the Mitochondrion.
... endosymbiosis attempts to bridge the gap between the organization of prokaryotic and eukaryotic cells and will highlight the evolutionary significance of anaerobic eukaryotes that do not have mitochondria. Endosymbiotic Theory The original theory behind the origin of the organelles in a ...
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The pathway of food through the digestive system.
... The enzyme protease works best at pH 2. The protease enzyme is produced in the stomach. Protease begins the digestion of proteins in the stomach. The large protein molecules are broken down to the smaller amino acids. Bile is produced ...
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The planned experiment is to measure the effect on the production of apple juice from apple pulp by varying the concentration of the enzyme pectinase.
... of ones, which already occur. As globular proteins, enzymes have a specific three-dimensional shape, which is determined by their sequence of amino acids. Despite their large overall size, enzyme molecules only have a small region that is functional. This is ...
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The Plasma Membrane
... plasma membrane is partially permeable so therefore some substances can cross more easily than others. A cell must also excrete waste products made in the cell through the cell's plasma membrane. There are many ways in which substances pass through ...
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The power output of a solar cell is proportional to the sine of the angle between the incident light and the face of the solar cell.
... to measure the angle being used for each reading when turning the Solar cell. Connecting Wires - used to complete the circuit and connect the components. Most of the apparatus I will use are self-explanatory. I am satisfied that the experiment will ...