Introduction to biology |Chapter 1 (part 2)|biology |class 9


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What is bioinformatics

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 INTRODUCTION TO BIOINFORMATICS Over the past few decades rapid developments in genomics and other molecular research technologies and, advancement in information technologies have combined to produce a tremendous amount of information related to molecular biology.  Bioinformatics is an evolving, interdisciplinary field of biology. Bioinformatics is the somewhat new and rather unfortunate term that is commonly employed for referring to the use of computers in biological research.  Bioinformatics is the application of mathematics/statistics and computer to the field of molecular biology. It is the name given to these mathematical and computing approaches used to glean understanding of biological processes.  The term bioinformatics was coined by Ben Hesper and Paulien Hogeweg in 1978 for the study of informatic methods in biological systems. Its primary use since the late 1980s has been in genetics & genomics, mainly in large-scale DNA sequencing area of genomics....
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chapter 2| solving a biological problem part2

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Study Of Malaria - An Example Of Biological Method    malaria is a common disease in many countries including Pakistan.   history  :In ancient times (more than 2000 years ago), physicians were familiar with malaria. They described it as a disease of chills and fevers with recurring attacks. They also observed that the disease was more common among people living in low, marshy areas. It was thought that the stagnant water of marshes poisoned the air and as a result of breathing in this “bad air”, people got malaria. This belief led to the name of this disease. The Italian words “mala” means bad and “aria” means air. For further clarification of the observation, some volunteers drank stagnant water from the marshes. They did not develop malaria. In the 17th century when the New World (America) was discovered, many plants from America were sent back to Europe to be used as medicines. The bark of a tree known as quina-quina was very suitable for curing fevers. It...
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shapes of molecules Valence Shell Electron Pair Repulsion |VSEPR

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The Shapes of Molecules (VSEPR Theory)  The shapes of molecules are  predicted and rationalize by  Va l ence  Sh ell Electron Pair Repulsion (VSEPR) theory .  The theory is based on minimizing the electrostatic repulsion between electron pairs, as first proposed by Sidgwick and Powell in 1940,   then generalized by Gillespie and Nyholm in 1957. Determine the number of lone pairs on the central atom in the molecule, and add the number of bonded atoms (a.k.a. bonding domains) the  steric number  defines the electronic shape of the molecule by minimizing repulsion. For example a steric number of three gives a trigonal planar electronic shape. The angles between electron domains are determined primarily by the electronic geometry (e.g., 109.5° for a steric number of 4, which implies that the electronic shape is a tetrahedron) These angles are adjusted by the hierarchy of repulsions: (lone pair - lone pair) > (lone pair - bond) > (bond - bond)
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