AIDS :- AIDS ( Acquired human Immune Deficiency Syndrome ) is pandemic disease, first recognised in USA ( 1981 ), believed to occured in Africa. First confirmed evidence of AIDS in India April 1986 ( 6 prostitutes from Tamilnadu were found HIV positive ). Causative agent :- HIV ( Human Immunodeficiency Virus ), it is […]
Communicable diseases :- Communicable diseases are diseases that can transfer from one person to another and caused by microbes like bacteria, protozoa, fungi, viruses, helminthes etc. Communicable diseases caused by bacteria :- Tuberculosis, Diphtheria, Whooping cough ( Pertussis ), Cholera, Other diarrheal disease, Leprosy, Tetanus, Gonorrhea, Syphilis etc. Communicable diseases caused by Viruses :- Mumps,
Communicable diseases, it’s Transmission, Symptoms, Prevention and Control Read Post »
पृथ्वी पर जीवो का क्रमबद्ध विकास हुआ है। आधुनिक क्रमविकास के सिद्धांत डार्विन के प्राकृतिक चयन पर आधारित है किंतु इसके पूर्व अनेक विद्वानों के द्वारा जीवो के विकास से संबंधित अनेक सिद्धांत प्रस्तुत किए गए जिन्हें वर्तमान में मान्यता प्राप्त नहीं हैं। क्रमविकास के सिद्धांतों में प्रमुख है लामार्कवाद तथा डार्विनवाद। लामार्कवाद (Lamarckism) :
लामार्कवाद क्या है? लामार्कवाद की मुख्य बातें तथा आलोचनाएं। नव-लामार्कवाद पर टिपण्णी। Read Post »
Theory of Evolution :- Modern theory of evolution is based on Darwin’s work related to the natural selection. It is not a hypothesis, theory of evolution includes Lamarckism, Darwinism. Lamarckism :- Jean Baptiste de Lamarck ( French ) published a book named Phylosophic Zoologique in 1809. In which he explained the process of evolution by
Evolution :- It is defined as a modification, In which a simple organism is changed into complex one. It is a very slow and irreversible process which can not be absorbed in a life time. Evidences of Evolution :- There are many evidences which prove that the evolution has taken placed. Indirect Evidences :- All
Origin of Life :- It is the natural process by which life has arisen from nonliving matter such as inorganic compounds. The life originated in the primitive Ocean on the Earth. As the distance from Sun increased, cooling process started. it resulted into the differentiation of regions – 1. Crust :- It is a outermost
आनुवंशिकता (Heredity) :- संतानो में पैतृक लक्षणों के संचरण को आनुवंशिकता कहते हैं। यह संचरण एक पीढ़ी से दूसरी पीढ़ी में जनकों से युग्मको (gametes ) के द्वारा होता है। आनुवंशिक लक्षण :- एक पीढ़ी से दूसरी पीढ़ी में संचारित होनेवाले लक्षण को पैतृक लक्षण या आनुवंशिक लक्षण कहलाते हैं। आनुवंशिकी (Genetics) :- जीव विज्ञान
डीएनए प्रतिकरण की विधियां (Methods of DNA Replication) :- डीएनए प्रतिकरण की विधियां निम्नलिखित हैं :– 1. प्रारंभन (Initiation) :- 2. कुंडली का खुलना (Unwinding of Helix) :- 3. प्राइमर स्ट्रैंड्स का निर्माण (Formation of Primer strands) :- 4. नए स्टैंड की लंबाई में वृद्धि (Elongation of new strand) :- संतत एवं अर्धसंतत प्रतिकरण (Continuous
डीएनए प्रतिकरण की विधियां क्या क्या हैं। संतत एवं अर्धसंतत प्रतिकरण के बारे में बताएं। Read Post »
आरएनए (RNA) :- आरएनए (Ribonucleic acid) एक प्रकार का न्यूक्लिक अम्ल है जो कोशिका द्रव्य तथा केंद्रिका में पाया जाता है। आरएनए को प्रथम आनुवंशिक पदार्थ कहते हैं क्योंकि आवश्यक जैवप्रक्रमों जैसे – उपापचयी, स्थानांतरण (ट्रांसलेशन), संबंधन आदि का विकास (evolution) आरएनए से ही हुआ था। कार्य :- आरएनए (RNA) की संरचना :- आरएनए (RNA)
Deviation without Dispersion :- Deviation produced by flint glass prism for a colour is equal and opposite which produced by crown glass prism. As a result, when the seven colours of light comes out through the flint glass prism, they combine to give a white light. Hence, there is no dispersion of light. This combination
Deviation without Dispersion And Dispersion without deviation Read Post »
Optical microscope:- The optical microscope, often referred as the light microscope. It is a type of microscope that uses visible light and a system of lenses to magnify images of small objects. There are two basic types of optical microscope. 1. Simple microscope. 2. Compound microscope. Simple microscope:- A simple microscope is actually a Convex
Human Eye :- The human eye is the most complicated Sense organ in the body with several parts fixed together form a spherical structure. Our eye is one of the most important optical device the nature has endowed us with. Sclerotic :- It is a tough and thick white sheat that protects the inner parts
