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Pleomorphism of Lysosomes

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  Pleomorphism of Lysosomes Lysosomes show pleomorphism, which means they occur in many different forms according to their functional state. They are not always identical in shape, size, or contents. Their appearance changes depending on whether they are newly formed, involved in digestion, or storing undigested waste materials.  Lysosomes are membrane-bound organelles containing hydrolytic enzymes. These enzymes digest proteins, lipids, carbohydrates, nucleic acids, and other cellular materials. Since lysosomes perform different digestive functions inside the cell, they appear in different structural forms. This property is called pleomorphism.  The main pleomorphic forms of lysosomes are primary lysosomes, secondary lysosomes, autophagic vacuoles, and residual bodies. Primary lysosomes are newly formed lysosomes produced by the Golgi apparatus. They contain inactive hydrolytic enzymes and have not yet taken part in digestion. They are small, spherical vesicles surround...
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Archaeopteryx-missing link

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Archaeopteryx lived during the early Tithonian stage of the Jurassic Period, around 150.8 to 148.5 million years ago. Most of the specimens of Archaeopteryx that have been discovered come from the Solnhofen limestone in Bavaria, southern Germany, which is a lagerstatte, a rare and remarkable geologicalformation known for its superbly detailed fossils. Archaeopteryx was roughly the size of a raven, with broad wings that were rounded at the ends and a long tail compared to its body length. It could reach up to 500 millimetres (20 in) in body length, with an estimated weight of 0.8 to 1 kilogram. Archaeopteryx feathers, although less documented than its other features, were very similar in structure and design to modern-day bird feathers. However, despite the presence of numerous avian features, Archaeopteryx had many theropod dinosaur characteristics. Unlike modern birds, Archaeopteryx had small teeth as well as a long bony tail, features which Archaeopteryx shared with other dinosaurs o...
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Prevention of Cancer and Dietary Guidelines Reduce Risk of Cancer

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  Prevention of Cancer People can do a great deal to prevent cancer by adopting the following behaviours.  Do not smoke  Cigarette smoking accounts for about 30% of all cancer deaths. Smoking is responsible for about 90% of lung cancer cases among men and 80% among women-about 85% altogether. Those who smoke two or more packs of cigarettes a day have lung cancer mortality rates 15-25 times greater than non-Smokers. Smokeless tobacco (chewing tobacco or snuff) increases the risk of cancers of the oesophagus, larynx, throat and mouth.  Avoid alcohol- Cancers of mouth, larynx, throat, oesophagus and liver are considered to occur more frequently among heavy drinkers, especially when accompanied by tobacco use (chewing tobacco or cigarettes). Avoid radiation- Excessive exposure to ionizing radiation can increase cancer risk. Even though most medical and dental X-rays are adjusted to deliver the lowest dose possible, un-necessary X-rays should be avoided. Do not suubathe -...
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