Discovery of virus

-
Discovery of virus

 Virus was discovered by a Russian scientist Ivonowasky in 1892 from Tobacco leaves.

Comments

Post a Comment

Popular posts from this blog

नाइट्रिक अम्ल ( Nitric acid )

-
Image
       नाइट्रिक अम्ल(Nitric acid)  इसे सर्वप्रथम ग्लॉबर ने सन 1658 में शोरे(पोटैशियम नाइट्रेट,KNO3) तथा सल्फ्यूरिक अम्ल के मिश्रण को गर्म करके बनाया था इसलिए इसे शोरे का अम्ल भी कहते हैं| बनाने की विधि - (1) प्रयोगशाला विधि- प्रयोगशाला में नाइट्रिक अम्ल को पोटैशियम नाइट्रेट या सोडियम नाइट्रेट की सल्फ्यूरिक अम्ल से क्रिया के द्वारा बनाया जाता है| KNO3 + H2SO4 ----> KHSO4 + HNO3  NaNO3 + H2SO4 ----> NaHSO4 + HNO3  इस विधि में एक रिटॉर्ट में पोटेशियम नाइट्रेट या सोडियम नाइट्रेट तथा सल्फ्यूरिक अम्ल को लगभग बराबर मात्रा में लेकर गर्म करने पर नाइट्रिक अम्ल की वाष्प उत्पन्न होती है, जिसे ग्राही फ्लास्क  में ले जाकर ठंडा करने पर यह द्रव अवस्था में प्राप्त हो जाता है| (2) औद्योगिक विधि - ओस्टवाल्ड की विधि- इस विधि में अमोनिया(1आयतन) तथा वायु(10 आयतन) के मिश्रण को एक उत्प्रेरक कक्ष में से प्रवाहित किया जाता है| उत्प्रेरक कक्ष का ताप लगभग 800°C होता है तथा इसमें प्लैटिनम की जालियां लगी होती हैं| प्लैटिनम उत्प्रेरक का कार्य करता है| इस ताप पर प्लैटिनम की उपस्थिति में अमोनिया की वायु की ऑक्सी
Read more

Nutrition in human beings

-
Image
Nutrition in human beings- Human beings are heterotrophic omnivorous organisms. They obtain their food from plants, animals and their products by holozoic mode of nutrition. The essential components of human diet are  water, carbohydrates, fats, proteins, minerals and vitamins. Human Digestive system- The human digestive system consists of an alimentary canal and many digestive glands. So human digestive system is divided into two main parts the first one is the alimentary canal and the other one is different digestive glands associated with alimentary canal. (1) Alimentary canal (2) Digestive glands associated with alimentary canal (1) Alimentary canal- The alimentary canal is a long tube with muscular walls, glandular epithelial lining and varying diameter. It extends from the mouth to the anal opening (anus). When uncoiled, the alimentary canal measures nearly 9 metre long tube in which the ducts of several digestive glands open to secrete their respective digestiv
Read more

Carbohydrates- Their Importance and Classification

-
Carbohydrates- Importance- The carbohydrates are often termed as sugars are the 'staff of life' for most organisms. On the basis of mass, they are the most abundant class of biomolecules in nature. Carbohydrates are also known as saccharides (sakcharon = Sugars or sweetness) since many of those of relatively small molecular weight have a sweet taste, although this is not true of those with large molecules. They are widely distributed molecules (moles = mass) in both plant and animal tissues. They are indispensable for living organisms, serving as a skeletal structures in plants and also in insects and crustaceans. They also occur as food reserves in the storage organs of plants and in the liver and muscles of animals. In addition, they are an important source of energy required for the various metabolic activities of the living organisms; the energy being derived as a result of their oxidation. They also serve to lubricate skeletal joints, to provide adhesion  between cell
Read more