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कोशिका ओर उसके प्रकार-1

  जब हम अपने चारों तरफ देखते हैं तो जीव व निर्जीव दोनों को आप पाते हैं । आप अवश्य आश्चर्य करते होंग एवं अपने आप से पूछते | होंगे कि ऐसा क्या है , जिस कारण जीव , जीव कहलाते हैं और निर्जीव जीव नहीं हो सकते । इस जिज्ञासा  का उत्तर तो केवल यही हो सकता है कि जीवन की आधारभूत इकाई जीव कोशिका की उपस्थित एवं अनुपस्थित है । सभी जीवधारी कोशिकाओं से बने होते हैं । इनमें से कुछ जीव एक कोशिका से बने होते हैं जिन्हें   एककोशिक जीव   कहते हैं , जबकि दूसरे , हमारे जैसे अनेक कोशिकाओं से मिलकर बने होते हैं   बहुकोशिक जीव   कहते हैं । कोशिका क्या है ? ( what in cell ? ) कोशिकीय जीवधारी ( 1 ) स्वतंत्र अस्तित्व यापन व ( 2 ) जीवन के सभी आवश्यक कार्य करने में सक्षम होते हैं । कोशिका के बिना किसी का भी स्वतंत्र जीव अस्तित्व नहीं हो सकता । इस कारण जीव के लिए कोशिका ही मूलभूत से संरचनात्मक व क्रियात्मक इकाई होती है । जिस प्रकार मकान छोटी छोटी ईंटों का बना होता हैं , उसी प्रकार प्रत्येक जीवधारी का शरीर भी एक या अनेक छोटी - छोटी रचनाओं का बना होता हैं , जिन्हें कोशिका ( cell ) कहते हैं । एन्टोनवान लिवेनहाक ने पहली
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Uk Lab assistant environmental supervisor Test -3

1. लेंस की शक्ति का मात्रक होता है:- [A] डायोप्टर [B] कैंडिला [C] मोल [D] केल्विन Ans. A 2. न्यून तापमान पैदा करने के लिए निम्नलिखित में से किस सिद्धांत का प्रयोग किया जाता है? [A] अतिचालकता [B] जूल-केल्विन प्रभाव [C] ताप-वैद्युत प्रभाव [D] रूद्धोष्म विचुम्बकन Ans. D 3. जब गर्म पानी को अपेक्षतया अधिक तप्त गिलास के ऊपर छिड़का जाता है, तो वह टूट जाता है इसका कारण है? [A] अचानक ही गिलास विस्तारित हो जाता है [B] अचानक ही गिलास संकुचित हो जाता है [C] जल वाष्पित हो जाता है [D] गिलास रासायनिक रूप से जल के साथ प्रतिकृत होता है Ans. A 4. एक निर्वात मार्जक भाप के अंतर-नियम के अनुसार कार्य करता है| चन्द्र में वह कैसे कार्य करेगा? [A] पृथ्वी के समान ही कुशल रूप से कार्य करेगा [B] कार्य नही करेगा [C] कम कुशलता से कार्य करेगा [D] अधिक कुशलता से कार्य करेगा Ans..b 5. चाक्षुष प्रदर्श एकक में प्राथमिक रंग होते है? [A] लाल, पीला, नीला [B] लाल, हरा, नीला [C] लाल, सफ़ेद, नीला [D] लाल, हरा, पीला Ans. B 6. आवर्धक लेंस वास्तव में क्या होता है? [A] अवतल लेंस [B] अवतल लेंस [C] उत्तल लेंस [D] बेलनाकार लें Ans. C
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Location: Roorkee, Uttarakhand, India
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FAMOUS NAME OF CROPS

 FAMOUS NAME OF CROPS Famous Name       :       Crops ∗ King of cereals : Wheat ∗ Queen of cereals : Maize ∗ King of coarse cereals : Sorghum ∗ King of coarse millets : Kodo (Paspulum scrobiculatum) ∗ King of pulses : Chickpea ∗ Queen of pulses : Pea ∗ King of oilseeds : Groundnut ∗ Queen of oilseeds : Sesame (Til) ∗ King of weeds : Congress grass (Parthenium hysterophorus) ∗ King of fruits : Mango ∗ Queen of fruits : Pineapple ∗ King of temperate fruits : Apple ∗ King of spices : Black Pepper ∗ Queen of spices : Cardamom ∗ King of vegetables : Potato ∗ Queen of vegetables : Okra ∗ Poor man’s meat : Soybean ∗ Wonder crop : Soybean ∗ Famine reserves : Millets ∗ King of fodder crops : Berseem ∗ Queen of fodder crops : Lucerne ∗ Vegetables meat : Cowpea ∗ Poor man’s fruit : Jackfruit, Ber ∗ Poor man’s substitute for ghee : Sesame ∗ Poor man’s friend : Potato ∗ Poor man’s food : Pearl millet ∗ King of Arid and semi arid fruits : Ber ∗ National fruit of India : Mango ∗ Glory of East : Chrys
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Location: Roorkee, Uttarakhand, India
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Father of different disciplines

  FATHERS OF DIFFERENT DISCIPLINES Father of Name ∗ Agronomy : Pietro Decrescenzi ∗ Agro climatology : Koppen ∗ Agro meteorology : D. N. Walia ∗ Agricultural chemistry : Justus von Liebig ∗ Antibiotics : Alexander Fleming ∗ ATP cycle : Lipmann ∗ Biology : Aristotle ∗ Botany : Theophrastus ∗ Bacteriology : Leuwenhoek ∗ Biochemistry : Justus von Liebig ∗ Crop rotation : Norfork (1730) ∗ Cytology : Robert Hooke ∗ Cytoplasmic inheritance : Carl Correns ∗ Cooperative movement in India : F. Nicholson ∗ DNA finger printing technique : Alec jeffrey ∗ Economic ecology : M.S.Swaminathan ∗ Ecology : Reiter ∗ Extension education : A. Seaman and Knapp (in USA) and Leagans (in India) ∗ Experimental genetics : Thomas Hunt Morgan ∗ Forest pathology : Robert Haring ∗ Fermentation : Louis Pasteur ∗ Field plot experiment : J. B. Boussingault ∗ Fruit and vegetable preservation : M. Nicholas Apart ∗ Genetics : Gregor Johann Mendel ∗ Genetic engineering : Paul Berg ∗ Green revolution : Dr. N. E. Borlaug  Gr
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Location: Roorkee, Uttarakhand, India
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Osmosis and diffusion

   MEANS OF TRANSPORT Diffusion • Passive movement and may be from one part of the cell to the other, or from cell to cell, or over short  distances, say, from the intercellular spaces of the leaf to the outside.  • No energy expenditure takes place.  • Molecules move in a random fashion, the net result being substances moving from regions of higher  concentration to regions of lower concentration.  • Diffusion is a slow process and is not dependent on a 'living system'.  • Diffusion is obvious in gases and liquids, but diffusion in solids rather than of solids is more likely.  • Diffusion is very important to plants since it the only means for gaseous movement within the plant body.  • Diffusion rates are affected by the gradient of concentration, the permeability of the membrane separating them, size of the substances, temperature and pressure. Facilitated Diffusion  :  • The diffusion of any substance across a membrane also depends on its solubility in lipids, the major  con
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Potato diseases..

   Late blight of potato : Phytopthora infestans Symptom : It affects leaves, stems and  tubers. Water soaked spots appear on  leaves, increase in size, turn purple  brown& finally black colour White  growth develops on under surface of  leaves. This spreads to petioles, rachis&  stems. It frequently develops at nodes.  Stem breaks at these points and the plant topples over. In tubers, purplish brown spots  and spread to the entire surface on cutting, the affected tuber show rusty brown necrosis spreading from surface to the center.  Pathogen The mycelium is endophytic, coenocytic and hyaline which are inter cellular with  double club shaped haustoria type. Sporangiophores are hyaline, branched intermediate  and thick walled. Sporangia are thin walled, hyaline, oval or pear shaped with a definite  papilla at the apex. The sporangium may act as a conidium and germinate directly to form  a germ tube. Zoospores are biflagellate possess fine hairs while the other does not. Mode of
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Red rot of sugarcane disease by jagmohan sir

  RED ROT OF SUGARCANE: This is one of the most severe of the known diseases of sugarcane. Causal Organism : Colletotrichum falcatum Symptom : The 3rd and 4th leaves (from the top) of the infected plants display yellowing and drying. At a later stage, show discoloured lesion on the rind. Fungal spores develop on rind and nodes. 3. If the diseased stalk split open, reddened internal tissues with intermingled white spots may be seen. The internal colour becomes brown, pith cavity become larger, greyish hyphae inside pith become visible. A sour and alcoholic smell emanates from the infected tissues. At a later stage, stalks become discoloured and hollow. Acervuli (black fruiting bodies) develop on rind and nodes. After splitting open the diseased stalk, a sour smell emanates. The internal tissues are reddened with intermingled transverse white spots. In advanced stage of the disease, the colour becomes earthy brown with pith cavity in the centre showing white cottony hyphae and sometimes
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PCR Polymerase chain reaction. By jagmohan sir

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   Polymerase chain reaction , or  PCR , is a technique to make many copies of a specific DNA region  in vitro  (in a test tube rather than an organism). PCR relies on a thermostable DNA polymerase,  Taq  polymerase , and requires DNA  primers  designed specifically for the DNA region of interest. In PCR, the reaction is repeatedly cycled through a series of temperature changes, which allow many copies of the target region to be produced. PCR has many research and practical applications. It is routinely used in DNA cloning, medical diagnostics, and forensic analysis of DNA. What is PCR? Polymerase chain reaction  ( PCR ) is a common laboratory technique used to make many copies (millions or billions!) of a particular region of DNA. This DNA region can be anything the experimenter is interested in. For example, it might be a gene whose function a researcher wants to understand, or a genetic marker used by forensic scientists to match crime scene DNA with suspects. Typically, the goal of
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