Thursday, February 26, 2009

CORRUPTION IN PUBLIC LIFE

CORRUPTION IN PUBLIC LIFE
In today’s century bribery, money laundering, fee for service rendered have become a way of life. Corruption at high level of political leadership travel downwards, Corruption has become inseparable part of life.
We often wonder which is the most corrupt department or section of the administration in India. The government officers and public figures have become microscopic minority. Giving and taking bribes have become so common now a day that people are adverse to think of public life without this phenomenon.
Corruption has almost paralyzed the entire system. Most government members of the public cannot expect officials to do their duty unless they get extra money. The government can tackle only if serious efforts are made to improve economic condition of the people. However, urgent need of the hour is to adopt a zero tolerance attitude towards it.

Sunday, February 22, 2009

Chromosomal Deletion

Chromosomal Deletion

Loss of a chromosome segment is known as deletion or deficiency. When the missing segment contains a telomere of the affected chromosome, it is called terminal deletion; such deletions are believed to be uncommon. In most deficiencies, however, the missing segment does not contain a telomere; such deletions are known as interstitial or intercalary deletions. In 1938, Muller postulated that the loss of telomere makes a chromosome end unstable so that it tends to unite with a similar damaged end. According to this view, all deficiencies that can be maintained in populations must be necessarily intercalary. This view is supported by considerable data reviewed by Roberts (1975) who believes that all supposedly terminal deletion are capped by very small telomeres, and, therefore, are intercalary. Thus the occurrence of really terminal deficiencies is doubtful; but some deletions in Drosophila may be terminal
DELETION IN MAN
Deletions have been described in human beings; each deletion appears to produce a distinct set of symptoms or ‘syndromes’. The group of symptoms that characterizes an abnormality or a disease is known as syndrome. A specific deletion in chromosome 22 produces a chromosome called ‘Philadelphia 22’; this chromosome is associated with chronic myelogenous leukaemia. Another deficiency in chromosome 5 produces ‘cri-du-chat’ syndrome. Individual’s sufferings from this syndrome produce a characteristic mewing catlike cry during childhood; have unique facial features and exhibit severe physical and mental retardation.

Wednesday, February 18, 2009

CELL DIVISION-MITOSIS

The term mitosis was used by Fleming in 1882. In mitosis, the two chromatids of each chromosome separate and move to the opposite poles of the cell. As a result, the two daughter nuclei produced by mitotic division of a nucleus contain the same number and kinds of chromosomes as did the parent cell. Somatic cell of the organisms divides through mitosis. In addition, cell in reproductive tissues undergo mitosis upto just prior to the mitotic division, and nuclei of the spores produced by meiosis also divides mitotically.
Development of embryos from zygote involves repeated mitotic division. In the initial stages, all the cell of a young embryo undergoes cell division. But as the development of embryo progresses, cell division becomes confined to some specific organs and tissues. In plants, mitosis is confined to the meristematic tissues of root and shoots tips, young leaves, flowers buds and cambium. In adult animals, mitosis is ordinarily confined to the organs concerned with the production of the blood cell, outer skin cells and gut epithelium. Healing of wounds and replacement of damaged organs in both plants and animals is based on mitotic cell division.

Saturday, February 14, 2009

CELL AND CELL THEORY

Z Janssen and H. Janssen were the first to the construct properly working compound microscope in 1590.Leeuwenhoek made notable improvements in the lenses of compound microscope. In 1665, Robert Hooke cut a thin section of cork and observed it under the microscope. He found that cork was made of large number of chambers similar to those of beehive. Hooke referred to these chambers as cells. In fact the cork cells were dead, and loving cells were never empty but they were filled with cytoplasm.
In 1824, Dutrochet concluded that all biological tissues are composed of cells and that these cells are attached with each other due to some adhesive compound. A few years later, in 1838, Schlieden published his studies on the structure of plant tissues and concluded that all plant tissues were made up of cells. In the next year, in 1839, Schwann concluded the same thing for animal tissues on the basis of his studies. Thus in 1839, conclusive evidence was presented to prove that all cell is a structural unit in both plants and animals, and it was postulated that cell is also a functional unit of all living organisms. These conclusions are popularly known as the Cell Theory, and it is credited to Schlieden and Schwann. In 1846, Nageli provided the logical extension of cell theory; he postulated that all the cells originate from preexisting cells. Virchow, in 1855, presented an elaborate version of this hypothesis alongwith considerable evidence in its support; it is referred to as Cell lineage theory and is credited to Virchow.

Wednesday, February 11, 2009

ANTIGENS

Immune responses arise as the result if exposure of foreign ‘stimuli’. The compound that evokes the response is referred to either as antigen or immunogen. An immunogen is any infectious agent capable of inducing an immune response. The antigen is any agent capable of binding specifically to lymphocytes/antibodies. All immunogen are antigens but not all antigens are immunogen.
There are three characteristic features that a compound must possess to immunogenic. They are foreignness, chemical complexity and higher molecular weight. Epitopes are the sites either on within the antigen with which the antibody reacts. They are also called as determinant groups or antigenic determinants. Haptens are low molecular weight compounds. They are antigenic and react with immune lymphocytes or antibodies, but they are not immunogenic, e.g. allergic response of some persons to penicillin. Penicillin is a hapten, it can couple with body protein and elicit an immune response.
The binding of antigens with antibodies or immunocompetent cells does not involve covalent bonds.
The binding may involve electrostatic interactions, hydrophobic interactions, hydrogen bonds and Vander Waal’s forces. The strength of the attraction between antigen and antibody is referred to as the affinity. Avidity refers to the strength of interaction between multivalent antigens and antibodies.

Sunday, February 8, 2009

AMINO ACIDS AND PROTEINS

Amino acids are the building blocks of proteins. All amino acids contain a carboxylic group and an amino group, both linked to single carbon atom called the 2 carbon. Although, there can many different kinds of amino acids, nearly 100, only 20 of them are commonly found in proteins in all classes of organisms ranging from bacteria to higher plants and animals. Proteins are polymers of 20 different amino acids. The primary responsibility of protein is to execute the tasks directed by the gene information. The protein serve as structural components of cells and tissues, act in the transport and storage of molecules (e. g. the transport of oxygen by haemoglobin ), transmit signals within and between cells ( e.g. harmones), provides defence against invading pathogens (e.g. immunoglobulin) and act as enzymes (e.g. pepsin, rennin).

Thursday, February 5, 2009

AUTOBIOGRAPHY OF SMOKE

Vehicles are a very good source of transportation. Industries help a lot to promote urbanization. But I cannot come up with the help of any other just vehicle is my father and an industry is my mother. I am black in color and black in my deeds. I grab others happiness and grab other needs its spread diseases and smoke is my name. Pollution and disease growth is nothing but my game. I begin from the vehicles, my room is atmosphere after a long time, and my grave becomes hydrosphere. I step into my grave through the acid rain. I give pain to others, but I have no gain, as I am loyal to earth, which has land and sea. So I warm all the people to beware of me. O sleeping man of earth wake up, please wake stir your harming sleep before the world shakes stop using leaded petrol, stop more vehicle usage make the chimneys. Higher is my only message. Every man on earth plants atleast one tree; this is the only way to make the earth pollution free.

Monday, February 2, 2009

Albert EINSTEIN

Albert EINSTEIN
A Man of inventions
ALBERT EINSTEIN was born in Germany, in 1879. He enjoyed the classical music and played the violin. Even as a small boy, EINSTEIN was self sufficient and thoughtful. He was a slow talker at first, pausing to consider what he would say. He would build up houses of cards to many stories to his concentration perseverance. Although he got good grades, he hated the academic high school. Once, one of his Teachers in the school suggested him to leave the school since his presence destroyed the other student’s respect for the teacher. Even at the age of nine, Einstein spoke hesitantly and his parent feared that he was below average intelligence. He was simply a thoughtful and somewhat shy child.
His Works

· He made clear how light ejects electrons from metals.
· He propounded ‘Brownian motion’, an unsolved mystery.
· He developed a relationship which is expressed in an equation: E=mc2
Einstein as Democrat:
The Outbreak of World War I in 1914 brought EINSTEIN’s thoughts about the abolishment of wars and development of peace, into public view. His attitude was based on deepest dislike to every kind cruelty and hatred. According to him everyman should be respected as an individual and no man should be idolized .He was against Adolf Hitler, the dictator of Germany and founder of Nazi party.
HIS PHILOSOPHY
How strange is lot of us mortals! Each of us is for a brief time, for what purpose I know not, though I sometime think I sense it. It is an irony of fate, that I myself have been recipient of excessive admiration and respect from my fellow beings through no fault and merit of my own. The cause of this may will be the desire unattainable for many to understand the few ideas to which I have been with my feeble powers attained through ceaseless struggle.
QUOTATIONS OF ALBERT EINSTEIN
· Imagination is more important than knowledge.
· The bitter and sweet comes from outside, the hard from within.
· God is subtle but he is not malicious.
· Natural hides her secrets because of her essential loftiness (moral goodness) but not by means of ruse (tricks).
· Don’t worry about your difficulties in mathematics; I assure you that mine are greater.
· Science without religion is lame, religion without science is blind.