Biospace

Now today we will study the Kingdom Monera and Archaebacteria. KINGDOM MONERA General characteristics Most of them are prokaryotic and are among the smallest organisms on earth. The nucleus is not well organised .i.e. the nucleus lacks nuclear membrane, nucleoplasm , chromatin fibres an also nucleoli . Cell Lacks membrane bound organelles like mitochondria , chloroplasts ,etc. 70 S ribosomes are present in the cell where S is the sedimentation co-efficient. Photosynthetic pigments are present in the form of chromatophores. The plasma membrane in folds to to form the mesosome which has the respiratory enzymes . The monerans posses cell wall except the mycoplasma and its composed of Peptidoglycan. They reproduce asexually for they lack sexual reproduction. The genetic material consists of a single DNA molecule and not particular pattern is followed while distribution of Genetic material. A process known as Mitosis Accomplishes this. They are primi

Q.1 Fill in the blanks with the help of following options : (John Needham ,Beijerinck , Joseph lister , Anton Van Leeuwenhoek) 1._________ coined the term Virus. 2._________ discovered that carbolic acid can be used as an antiseptic during surgery. 3. __________ was the first to see and describe micro-organisms. 4. ________ proposed the existence of 'Life force'. Q.2. Answer the following in 2-3 sentences : 1.Explain Agricultural Microbiology. 2.Give any three supporters of theory of Biogenesis. 3. Explain the Golden era of Microbiology. 4. What is the Germ theory of diseases? Q.3. Answer the following in 5-6 sentences : 1. What are the Koch's Postulates? 2. What is tyndallization as well as pasteurization? 3. What are the River's Postulates? 4. Describe any four fields of microbiology and explain them in brief. Q.4. Explain in detail (10-12 sentences) :  1. Give an account on contribution of Louis Pasteur in Microbiology. 2. What is the theory

Here today we will study which organisms do we have to study in microbiology. Microbiology includes study of all micro-organisms i.e. it includes Bacteria's , Viruses , Fungi , Protozoans and Algae. Some of them are prokaryotic and some of them are Eukaryotic. Now let us see the difference between them- Now let us study each of the type of microbes mentioned above - 1. Bacterias Usually size ranges from 0.2 to 100 micrometres Prokaryotic , unicellular , simple internal structure  Can be grown on artificial laboratory media Reproduction is usually asexual characteristically by simple cell division Significance- Some cause disease , some perform important role in nutrient cycles leading to fertility of soil, Useful in industries for production of compounds, some spoil while so make foods. Examples - Methanococcus , Mycoplasma , etc. 2 . Viruses Acellular and size varies from 0.015 to 0.2 micrometres They all are obligate parasites so need living host

Let us study the Last era i.e. the Post-Golden Era in the history of Microbiology as well as Biocomplexity today- Post-Golden Era-  20th century Rapid development in microbial information This was the modern era of Microbiology Development of Various streams of Microbiology Louis Pasteur  and Robert Koch worked significantly and discovered how pathogens infect and vaccination against the same were discovered. They led to extensive developments in Applied Microbiology, immunology and medical microbiology. Beijerinck led to significant discoveries in Agricultural Microbiology and was the one to discover first Virus. George Beadle and Edward Tatum succeeded in isolating mutants of Neurospora. Further experiments in Genetics and molecular microbiology were carried out by Avery, McLeod and McCarty. Later on Watson and crick and others elaborated the structure of DNA chemically.  Further M.Nirenberg ,Hargobind Khurana R.W.Holly etc added great deal of information. W.Gi

Let us study the next era i.e. the Golden Era in the history of Microbiology. Golden Era-  Period between 1865 and 1882 Foundations of the new science were laid The pioneer work Louis Pasteur , Robert Koch and Joseph Lister during this period was noteworthy. Contributions of Louis Pasteur Louis Pasteur was the great pioneer in the studies of fermentation He showed that yeast is required to convert sugar to alcohol. He showed that specific organisms bring about different fermentation. He eventually convinced the world that fermentation process is a result of microbial activity. He discovered that the spoilage of beer and wines lead to the growth of unwanted micro-organisms. He developed a method to remove undesirable microbes from juice without affecting its quality.Heating the juice for half an hour at 62.8 C did the job. This Technique is known as pasteurization. This technique is now used widely in the wine and milk industry. Germ Theory of Diseases Acco

We will learn the history of Microbiology today... Let us start with the Pre-Golden Era. Pre-Golden Era-  Period before 1865 Experienced slow accumulation of some facts about bacteria's Theory of Abiogenesis Previously it was considered that living organisms or creatures arise from non-living matter. This belief is referred to as theory of spontaneous generation or Abiogenesis. Frogs, flies and mice were believed to have originated spontaneously from soil, fertile mud , decaying living organisms, etc. Aristotle was in support of this theory of abiogenesis. Virgil and helmont were also in the favor of the same. Discovery of Microscope Robert Bacon was the first who described lens for the first time. Hans and Janssen produced a first microscope of crude type. Gallielo Galleilee had also made a microscope with a focusing device. Fabri gave the name 'Microscope'. Discovery of Microbial Life Robert hooke had observed cells in the cork of a stem

This is my first article related to my other topic Microbiology. I will discuss topics of both the branches simultaneously.So let us study what is microbiology in this topic. What is Microbiology? Microbiology is the study of micro-organisms including the bacteria's and all other unicellular, multicellular or acellular microbes. It is a well developed science and is studied under various streams like bacteriology, virology , Molecular biology , plant pathology , Immunology, applied microbiology and many more. Its very interesting branch with a very huge scope. Many events took place in the development of microbiology and its various streams. We will study the history and all the events in the developmental process in the next article. What are we going to study next : I. Various Era's in the development of the microbiology A. Pre-Golden Era- Discovery of microscope Discovery of Microbial life Theory of spontaneous generation B. Golden

Now in this part we will study : A. Test cross or back cross B. Deviations from Mendelian Ratios-      Genetic Interactions      1. Intragenic interactions          a. Incomplete Dominance          b. Co-Dominance          c. Multiple Alleles      2. Intergenic interactions          a. Pleiotropy          b. Polygenes A. Test cross or back cross    Test cross is a simple method devised my Mendel to verify or test the F1/F2/F3 Hybrids. In test cross F1 hybrid is crossed  with the homozygous recessive plant. Since the offspring is crossed back with one of the parents, it is also back cross. A test cross s a back cross but a back cross is not always a test cross because in test cross we cross the F1 hybrid compulsorily with the recessive parent and in back cross we can choose any one of the two parents.  The ratio obtained is always 1:1 which is known as the test cross ratio. Here is an example of test cross- B. Deviations from Mendelian Ratios- A