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Nanocapsules....and it's structure and method
Nanocapsules and it's structure and preparation ,scope in medicine
£4.06 Preview RemoveBest IGCSE Chemistry notes
A must have! Everything you need to know to succeed in IGCSE Chemistry
£6.25 Preview RemoveBiology Notes
Respiratory Disorders: There are numbers of respiratory disorders which effect people. The percentage of such disorders is particularly high in Pakistan.it is due to the more concentration of air pollutants not only in the urban but also in the rural atmosphere. some of the important respiratory disorders are described next. 1-Bronchitus: Bronchitis is the inflammation of the bronchi or bronchioles.it results in excessive secretions of mucus into the tubes, leading to the swelling of tubular walls and narrowing of tubes (below fig).it is caused by viruses, bacteria or exposure to chemical irritants (e.g. Tobacco smoke) there are two major types of bronchitis i.e acute and chronic. The acute bronchitis usually lasts about two weeks and patients recover with no permanent damage to the bronchi or bronchioles .in chronic bronchitis, the bronchi develop chronic inflammation.it usually lasts for three month to two years. Symptoms Of Bronchitis: Symptoms of bronchitis include an cough,mild wheezing,fever,chills,and shortness of breath(especially when doing hard job).|the majority of people diagnosed chronic bronchitis are 45 year of age or older.| 2: Emphysema Emphysema is the destruction of walls of the alveoli.it result in larger sacs but with less surface area for gaseous exchange (below image)As lungs tissues breaks down, the lungs do not come back to their original shape after exhalation.so air cannot be pushed out and is trapped in the lungs. Symptoms of Emphysema: The symptoms of emphysema include shortness of breath, fatigue, recurrent respiratory infection and weight loss, by the time the symptoms of emphysema appear, the patient has usually lost 50% to 70% of his/her lung tissue the level of oxygen in blood may get so low that it causes serious complications. 3-Pneumonia Pneumonia is an infecting of lungs. If the infections affect both lungs then, it is called double pneumonia. The most common cause of Pneumonia is a bacterium, streptococcus Pneumoniae. Some Viral (influenza virus) and fungal infections may also lead to pneumonia. Aused by When the causative organisms enter the alveoli, they settle there and grow in number. They break the lung tissues and the area becomes filled with fluid and pus. The symptoms of pneumonia include a cold that is followed by a high fever, shivering, and a cough with sputum production. Patient may become short of breath. The patient’s skin colour may change and become dusky or purplish.it is due to poor oxygenation of blood. 3-Pneumonia Vaccines are available to prevent pneumonia caused by S.Pneumonia . Antibiotics are used in the treatment of this type of pneumonia. |Prior to the discovery of antibiotics, one third of pneumonia patients died from the infection.| 4-Asthma Asthma is a form of allergy, in which there are inflammation of the bronchi, more mucous production and narrowing of the airways. In asthma patients, The bronchi and bronchioles become sensitive to different allergens (allergy causing factors)e.g. Dust,smoke,perfumes,pollens etc. When exposed to any of such allergens the sensitive airways show immediate and excessive response of constriction. In this condition, The patient feel difficulty in breathing. Symptoms of asthma: The symptoms of asthma vary from person to person.The major symptoms include shortness of breath (especially with exertion or at night), wheezing(whistling sound when breathing out),cough and chest tightness. The chemicals with ability to dilate the bronchi and bronchioles are used in the treatment of asthma .such medicine is given in the form of inhalers. 5-Lung Cancer(parti) Lung Cancer is a disease of uncontrolled cells divisions in the tissues of the lung. The cells continue to divide without any control and form tumors. The cellular growth may also invade adjacent tissues beyond the lungs. The most common symptoms are shortness of breath, coughing (including coughing up blood) and weight loss. The main causes of any cancer include carcinogens (such as those in cigarette smoke).ionizing radiation and viral infection. Smoking is the main cause of lung cancer. The risk of lung cancer is significantly lower in non-smokers. Cigarettes smoke contains over 50 known carcinogens. 5-Lung Cancer(partII) Passive smoking (the inhalation of smoke from another smoking )is also a cause of lung cancer .the smoke from the burning end of a cigarette is more dangerous than the smoke from the filter end. Eliminating tobacco smoking is a primary goal in the prevention of lung cancer. The world health organization has called for governments to stop tobacco advertising to prevent young people from taking up smoking. |if a person stop smoking ,the chance to develop cancer decease as damage to the lungs is repaired and contaminant particles are gradually removed|. Bad effects of smoking: Smoking is harmful due to the chemicals in cigarettes and smoke. Tobacco smoke contains over 4000 different chemicals out of which at least 50 are carcinogens and many are poisonous. |Nicotine is a powerful poison and was widely used as an insecticide in the past. When inhaled through tobacco smoking .it reaches our circulatory system and not only hardens the walls of the arteries but also damages the brain tissues|. 5-Lung Cancer(partII) Many people think that lung cancer is the only smoking-related disease and it is the number one cause of death among smokers .but it is not right .cigarette smoke affects the body from head to toe. Smokers have a much higher risk of developing a number of life threatening diseases. |according to the W.H.O the rates of smoking have declined in the developed world. In the developing world however it is rising by 3.4% per year as of 2002 the world no tobacco day is celebrated on the 31st of may every year|. Bad effects of smoking: Smoking may also lead to the cancer in kidneys. Oral cavity larynx ,breast ,bladder ,and pancreas etc. Many chemicals are tobacco smoke damage the air passageway, which leads to emphysema and other respiratory disorders. Smoking also has effect s on the circulatory system. The carbon monoxide present on tobacco smoke lessens the oxygen-carrying capacity of hemoglobin. Many other chemicals in smoke increase the production of blood platelets. When platelets are more than the normal numbers, they make the blood viscous and it can lead to arteriosclerosis. |Non-smokers who are exposed to Second-hand smoke(passive smoking)at home or work increase their heart disease risk by 25-30% and theit lung cancer risk by 20-30%|. Smoking risk: Smokers are the great risk of developing infections, particularly in the lungs. For example, smoking increases the risk of tuberculosis by two to four times, and of pneumonia by four times. |smoking also affect the social life of a person. smokers may face the social un-acceptance because other people may not want to be exposed to other’s smoke|. Smoking also responsible for weakening and staining the teeth. Tooth loss is 2 to 3 times higher in smokers than in non-smokers. HOMEOSTASIS IN PLANTS Plaints respond to the environmental changes and keep their internal conditions constant i.e Homeostasis. They apply different mechanism for the homeostasis of water and other chemicals (oxygen carbon dioxide nitrogenous material etc). Removal of Extra carbon dioxide and oxygen: In daytime the carbon dioxide produced during cellular respiration is utilized in photosynthesis and hence it is not a waste product. Removal of Extra carbon dioxide and oxygen: At night it is surplus because there is no utilization of carbon dioxide.it is removed from the tissues cells by diffusion. Leaves and young stems, carbon dioxide escapes out through stromea.in young roots carbon dioxide diffuses through the general root surface especially through root hairs. Oxygen is produced in mesophyll cells only during daytime, as a by-product of photosynthesis. After its utilization in cellular respiration, the mesophyll cells remove the extra amount of oxygen through stomia. Removal of extra Water: We know that plants obtain water from soil and it is also produced in the body of during cellular respiration. Plants store large amount of water in their cells turgidity. Extra water is removed from plant body by transpiration. Removal of extra Water: At night transpiration usually does not occur because most plants have their stomata closed. If there is higher water content in soil, water enters the roots and is accumulated in xylem vessels. Some plants such as gasses force this water through special pores present at leaf tips or edges and form drops. The appearance of drops of water on the tips or edges of leaves is called guttation. Recalling: Transpiration Is the Loss of water From Plants Surface in the form of Vapours. Guttation is not to be confused with dew, which condense from the atmosphere onto the plant surface. Removal of other Metabolic Wastes: Plants deposit many metabolic wastes in their bodies as harmless insoluble materials. For example, calcium oxalate is deposited in the form of crystals in the leaves and stems of many plants e.g in tomato. In trees which shed their leaves yearly, the excretory products are removed from body during leaf fall. Others waste materials that are removed by some plants are resins(by coniferous trees) gums(by keekar) latex(by rubber plant) and mucilage(by carnivorous plants and ladyfinger) |the removal of excretory products is a secondary function of leaf fall.if the leaves are not shed,the calcium oxalate just remains as harmless crystals in the leaf|. Osmotic adjustment in Plants: On the basis of available amount of water and salts, plants are divided into three groups. Hydrophytes: Hydrophytes are the plants which live completely or partially submerged in freshwater. Such plants do not face the problem of water shortage. They have developed mechanisms for the removal of extra water from their cells. Hydrophytes have bored leaves with a large number of stomata on their upper surfaces. This characteristic helps them to remove the extra amount of water. The most common example of such plants is water lilly. Xerophytes: Xerophytes live in dry environments. They possess thick, waxy cuticles over their epidermis to reduce water loss from internal tissues. They have less number of stomata to reduce the rate of transpiration. Such plants have deep roots to absorb maximum water from soil. Some xerophytes have special parenchyma cells in stems or roots in which they store large quantities of water. This makes their stems or roots wet and juicy, called succulent organs. Cacti (singular: cactus) are the common examples of such plants. |Recalling: osmosis is the movement of water from hypotonic solutions(less solute concentration) to hypertonic solutions (higher solute concentration)through semipermeable membrane|.
£187.50 Preview Removechemical properties of alcohols
Alcohols are the family of compounds that contain one or more hydroxyl (-OH) groups attached to a single bonded alkane. Alcohols are represented by the general formula -OH. Alcohols are important in organic chemistry because they can be converted to and from many other types of compounds.
£3.75 Preview RemoveChemistry - Question and Answers
1. Which correctly describes the structure of an atom? A. There are always the same number of protons and neutrons. B. There are always the same number of protons and electrons. C. There are always the same number of neutrons and electrons. D. The number of protons, neutrons, and electrons is always the same E. There are never the same number of neutrons and protons. 2. What directly determines an atom's identity? A. the number of electrons B. the number of neutrons C. the number of protons D. the number of bonds it can form E. the ratio of protons to electrons 3. Carbon12 and carbon14 are isotopes. How are they different from each other? A. different numbers of protons B. different numbers of neutrons C. different numbers of electrons D. they can form different numbers of chemical bonds E. different number of energy shells 4. Which is a covalent bond? A. two atoms share innerorbit electrons with each other B. a bond between water molecules C. a bond between two oppositely charged ions D. a bond between two free radicals E. two atoms share outer orbit electrons with each other
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