... elongated cells having heavy lignified cell walls. When plants reach maturity the fibre cells are dead, only supporting the plant stems and roots. Fibres are one of the main components of sclerenchyma tissue, along with other cells, which produce the ...

... are hydrophobic ("water hating") and non-polar. The hydrophilic head bears electrical charges contributed by the phosphate and some bases. These charges are responsible for the hydrophilicity. No lipid bears a positive charge they are all negative or neutral. Therefore all ...

... of the benefits of "aerobic exercise" is that it improves your body's ability to make ATP rapidly using the respiration process. All living cells have mitochondria. Hair cells and outer skin cells are dead cells and no longer actively producing ATP, ...

... acid, the zwitterion form of the amino acid acts as a buffer by taking up H+ ions to keep the concentration oh hydrogen constant, and hence to raise the pH. However, when in an alkaline solution, the amino acid acts as ...

... complexed with some other lipids do so by the information of covalent chemical bonds. Properties such as solubility or viscosity, helps it to orient correctly in a membrane, or make it recognizable to another biochemical or cell. The term primary structure ...

... in the nucleus is the nucleolus. Ribosomes Ribosomes are protein builders. They connect amino acids together and build long chains. Ribosomes are found in many places around the cell. Ribosomes which are found floating around the cytoplasm are making protein which ...

... the concentration gradient. * The villi possess smooth muscle fibres that contract and relax and mix the food up and bring it into contact with the epithelial cells of the absorptive surface. * Each villus has a lacteal for the ...

... 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 ...

... are extremely small and thin, so to examine them you need to use an electron microscope. Under the electron microscope they look like solid structures, but they actually move constantly, joining with other membranes. By using the electron microscope we ...

... in which anhydroglucose units are linked by a-D-1,4 glucosidic bonds to form linear chains. The level of amylose and its molecular weight vary between different starch types. Amylose molecules are typically made from 200-2000 anhydroglucose units. Aqueous solutions of amylose ...

... The Prokaryotic Cell The Eukaryotic Cell Scientists believe that the eukaryotic cell originated from several different types of prokaryotic cell, hence the similarities between the two cell types. The contents of both cells are suspended in the cytoplasm, ...

... It lies close to the POSTSYNAPTIC MEMBRANE of the adjacent cell. Between the two membranes is a 20nm wide SYNAPTIC CLEFT. Function of Synapses 1. Prevents impulses travelling in the wrong direction. An impulse can pass along an axon in either direction, ...

... and Cyanobacteria predominate. In anaerobic conditions polluted or eutrophic waters, other photosynthetic bacteria are dominant. Photosynthesis of algae Photosynthesis (converting light energy into chemical energy) is performed in parts of the cell called chloroplasts. They can be found in different shapes and ...

... other with sufficient energy for the reaction to take place. This is collision theory. You can speed up the reaction by rising the temperature. A successful collision may require that the two molecules or species must collide with the correct ...

... 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 the anarobic bacterium. When the original anerobic bacterium reproduced, so did the aerobic bacterium inside it, so all offspring ...

... 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 the anarobic bacterium. When the original anerobic bacterium reproduced, so did the aerobic bacterium inside it, so all offspring ...

... here. Disaccharides are used as an energy source and are found in most foods i.e. natural cane sugar (sucrose) and are sweet and soluble. They usually occur as intermediates either in the building or breaking down of polysaccharides. They are also ...

... away from the water. In relating this to a plasma membrane two lines of lipids are present in a membrane, they arrange themselves such that the hydrophilic ends of each lipid on the first line (the inside part of the ...

... improve the life standards of the sufferer the fundamental fact is that this disease is carried through the genes of the sufferer and currently can not be prevented or even effectively treated. (2) 2. Possible solution With no feasible cure for cystic ...

... more effectively than non-enzyme detergents. However, using modern bleaching and brightening agents, the difference between looking clean and being clean may be difficult to discern. At present only proteases and amylases are commonly used. Although a wide range of lipases ...

... antibiotics, but the chance that one bacterium may have the resistance gene means resistance can be a huge problem. But in contrast it has been found that the effectiveness of antibiotics can help many in their fight against cancer, with ...

... makes them move faster. This results in an increase in the number of collisions between enzymes and substrate molecules, meaning that more of the desired product will be made in less time. Other factors which affect enzyme activity include pH ...

... the effects of enzymes such as pectinase, slowly breaking down this pectin layer. However it is not entirely known exactly which enzymes are responsible for this development. It is hoped that one day it may be possible to monitor this ...

... in medicine. Enzymes have many uses in medicine. Streptokinase helps to dissolve blood clots which limits the chance of a further heart attack. In addition, Urokinase removes blood clots, for example in heart disease by breaking down the blood clots. The ...

... enzymes for analysis. These two enzymes are immobilised (entrapped in an inert insoluble matrix in the process of immobilisation) onto a cellulose fibre pad. These pads forms the basis of Clinistix and Diastix. Glucose analysis (biosensors) allows quick, sensitive and ...