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The science behind Lionel Messi’s Greatness What was Lionel Messi’s childhood like Lionel Messi started playing football as a boy and was noticed by clubs on both sides of the Atlantic. When he was 13, his family relocated to  Barcelona . He played for  FC Barcelona ’s under-14 team, quickly graduating through the higher-level teams until his informal debut at age 16 with FC Barcelona in a friendly match. What are Lionel Messi’s achievements? Lionel Messi scored 73 goals during the 2011–12 season while playing for  FC Barcelona , breaking a 39-year-old record for single-season goals in a major European football league. In 2014 Messi led Argentina to the  World Cup  final for the first time in 24 years; Argentina lost, but Messi won the Golden Ball award as the tournament’s best player. During the 2016 Copa América Centenario tournament, he netted his 55th international goal to break  Gabriel Batistuta ’s Argentine scoring record. He led Arg...

The second Law of thermodynamics explained The second law of thermodynamics asserts that heat cannot move from a reservoir of lower temperature to a reservoir of higher temperature in a cyclic process. Rudolf Clausius, a physicist who first formulated the law, stated that “a cyclic transformation whose only final result is to transfer heat from a body at a given temperature to a body at a higher temperature is impossible.” The law describes the amount of work that can result from a transfer of heat What are some applications of the second law of thermodynamics? One notable example of the second law of  thermodynamics  is the  heat engine  model. Heat engines involve a cycle of increasing and decreasing temperatures that move a piston. The second law of thermodynamics dictates the amount of work that the changing temperatures in a heat engine can produce. The law is often applied to various types of engine How does the second law of thermodynamics relate to biology? ...

WHAT REALLY HAPPENED TO THE DINOSAURS One day 66 million years ago, an asteroid the size of a mountain struck near the Yucatán Peninsula with an explosive force equivalent to 100 trillion tons of TNT. In that cataclysmic instant, the 165-million-year reign of the dinosaurs came to an end. The asteroid theory of the dinosaurs’ demise was first suggested in 1980. More than a decade later, the identification of the Chicxulub Crater in the Gulf of Mexico established where and when. Using an impact calculator developed by geophysicists from Purdue University and Imperial College London, researchers obtained a pretty good idea of what occurred at the moment of impact and immediately after—what is known as the K-Pg (Cretaceous-Paleogene) extinction event. The asteroid struck the Earth at 40,000 miles (64,000 kilometres) per hour, creating a crater more than 115 miles across and instantly vaporizing thousands of cubic miles of rock. Any creature close enough to witness the strike was immediate...

Did humans and dinosaurs live at the same time? What if humans and dinosaurs really coexisted? This question is an easy one to answer — and it’s an unfortunate, but firm, no (with one notable exception). Humans and non-avian dinosaurs never shared planet Earth together. We did not ride them, nor keep them as pets or harness them for domestic labor. The data here are quite solid. The non-avian dinosaurs died out 66 million years ago, likely when an asteroid struck Earth and the ensuing cataclysm wiped out a large percentage of life on the planet. This included almost every large organism, and most of the small ones as well. In the aftermath, one relatively humble group was able to carve out a much larger footprint for itself: the mammals. These were the creatures that would one day lead to us, after much evolutionary progress and most of the 60-odd million years separating us from the end-Cretaceous mass extinction. Humans and Dinosaurs Timeline At some point in the past half-dozen mill...

Chemistry - Zinc Introduction In the periodic table, zinc is the first element of group 12. The symbol of zinc is  ‘Zn’  and the atomic number is  ‘30.’ In terms of availability, zinc is the 24 th  most abundant element found in the Earth's crust and it has five stable isotopes. The most common zinc ore is sphalerite (zinc blende), which is a zinc sulfide mineral. Andreas Sigismund Marggraf, the German chemist, first discovered the pure metallic zinc in 1746. Interestingly, alchemists burned zinc in the air and form something different thing and they named that  "philosopher's wool"  or " white snow ." Salient Features of Zinc Zinc’s color is bluish-white and it is lustrous and diamagnetic metal. Zinc metal is normally hard and brittle; however, at when the temperature increases from 100 0 C, it becomes malleable. When temperature increases 210 0 C, then the zinc metal again becomes brittle and can be pulverized easily by beating. Zinc is a conductor of ele...

Chemistry - Gold Introduction Gold is a bright, reddish yellow, soft, dense, malleable, and ductile metal naturally found in the earth’s crust. The symbol of gold is  ‘Au’  and atomic number is  ‘79.’ Gold is (chemically) a transition metal and belongs to group 11 of the periodic table. Salient Features of Gold Gold, which remains in a solid state under standard conditions, is the least reactive element. Gold is resistant to most of the acids. Gold does dissolve in aqua regia; aqua regia is a mixture of nitric acid and hydrochloric acid. However, gold is insoluble in nitric acid. Gold usually dissolves in alkaline solutions of cyanide. Cyanide solutions are commonly used in mining and electroplating. Gold also dissolves in mercury and forms  ‘amalgam alloys.’ Gold does not react with oxygen at any temperature. Occurrence of Gold Gold commonly occurs as a free element i.e. in the natural form. Gold occurs as nuggets or else found in in rocks, grains, in veins, and in ...

Chemistry - Metallurgy The branch of science and technology that studies the properties of metals and their production and purification is known as  metallurgy . Naturally occurring solid inorganic substance is known as a  mineral . Naturally occurring solid material from which valuable mineral or metal can be extracted is known as  ore . The following table illustrates the major elements and their ores − Element Ores Chemical Composition Aluminum Bauxite Al 2 O 3 2H 2 O Corundum Al 2 O 3 Kryolite Na 3 AlF 6 Dyspore Al 2 O 3 .H 2 O Copper Copper Pyrite CuFeS 2 Malachite 2CuCO 3 Cu(OH) 2 Iron Hematite Fe 2 O 3 Magnetite Fe 3 O 4 Siderite FeCO 3 Sodium Sodium Carbonate Na 2 CO 3 Sodium Chloride NaCl Sodium Nitrate NaNO 3 Sodium Sulphate Na 2 SO 4 Potassium Potassium Chloride KCl Potassium Carbonate K 2 CO 3 Potassium Nitrate KNO 3 Magnesium Magnesite MgCO 3 Dolomite CaMg(CO 3 ) 2 Epsom Salt MgSO 4 Calcium Calcium Carbonate CaCO 3 Tin Cassiterite SnO 2 Lead Galena PbS Ceruss...

Fats Introduction Fat is a significant foodstuff for many forms of life. Fats serve structural as well as metabolic functions. The fats are molecules made up of glycerol and fatty acid. Fat is an organic compound of hydrogen, carbon, oxygen. Based on the number and bonding of the carbon atoms, fats and oils, are categorized in the aliphatic chain. fats and oil Functions of Fats Following are the major functions of Fats − Fat is a vital dietary requirement. The fat is usually the stored source of energy in the body that remained store beneath the skin. Fat acts a protective layer especially in the human body and provide protection. Some of the vitamins such as vitamin A, vitamin D, vitamin E, and vitamin K are fat-soluble, which means they can only be absorbed, digested, and transported in conjunction with the fats. Fats actively help in maintaining the healthy skin and hair. Fats insulate body organs against external shock. Fats also maintain body temperature. Fats promote healthy cell...

 Proteins proteins Introduction Proteins, which are basically biomolecules, play wide range of functions in the body of a living organism. Proteins are made up of tiny elements of different types of amino acids. A sequence of amino acid residues in a protein is known particularly by the sequence of a gene; gene is encoded in the genetic code. After formation, proteins exist for a fixed period of time and are then degraded and recycled. The proteins get recycled by the cell's machinery by the process of protein turnover. Most of the proteins contain linear polymers made up of series of up to 20 different L-α-amino acids. The amino acids in a polypeptide chain are connected by peptide bonds (see the image given below). The peptide bond, usually, has two resonance forms, which contribute some double-bond characters. Protein Structure Most of the proteins illustrate unique 3-dimensional structures (see image given below). protein enzyme combining However, proteins have not a rigid stru...

Carbohydrate Introduction Consisting of oxygen (O), carbon (C), and hydrogen (H), carbohydrate is a biological molecule. Carbohydrate is one of the essential elements for the living organisms, as it plays various important roles. carbohydrates Carbohydrate is the main source of energy, as about two-third energy requirement of living beings is fulfilled by it. Glucose, sugar, and starch are the important examples of carbohydrate. Source of Carbohydrate Carbohydrates naturally are occurring in wide variety of foods, such as − Wheat Maize Rice Potatoes Sugarcane Fruits Table sugar Bread Milk Sugar that we eat in our everyday life is mainly sucrose (table sugar). Sucrose is added in many food items while preparing, e.g. jam, biscuits, cakes, energy drinks, etc. Further, many fruits naturally contain glucose and fructose. Glycogen is another type of carbohydrate that found in the liver and muscle. Cellulose found in the cell wall of plant cells is carbohydrate. Types of Carbohydrate The fol...

 Branches of Biology branches of biology The following table illustrates the different branches of biology with their brief description − Branch Studies Anatomy Study of the internal structure of an organism Aerobiology Study of airborne microorganisms Agronomy Study of soil management and crop production Agrostology Study of grasses Araneology Study of spiders Actinobiology Study of the effects of radiation upon living organisms Angiology Study of the diseases of the circulatory system and of the lymphatic system Bioinformatics of collecting and analyzing complex biological data including genetic codes through computer technology Biotechnology Use of cellular and biomolecular processes to develop technologies and products, which ultimately help to improve human lives and the health of the planet. Biochemistry Study of chemical and physio-chemical processes and substances, which occur within the living organisms. Batrachology Study of amphibians including frogs and toads Bioclimato...

Blood Group Introduction Based on the presence and absence of antibodies, the blood is classified into different groups. Further, while classification, the presence and absence of the inherited antigenic substances also considered. different blood groups The types of blood groups are inherited and represent contributions from both the father and the mother. ABO Blood Group System In human blood, usually, there are two antigens and antibodies. The two antigens are antigen A and antigen B. The two antibodies are antibody A and antibody B. The antigens are remaining in the red blood cells, whereas the antibodies are found in the serum. Based on the antigen property, the blood group of all human beings can be classified as − Blood Group A  − antigen A and antibody B Blood Group B  − antigen B and antibody A Blood Group AB  − antigen A and antigen B and no antibody Blood Group O  − no antigen, but antigen A as well as antibody B Consideration of the ABO system is the most...

Natural Resources Introduction The resources, available on the Earth and the energy being received from the Sun, are essential to meet the basic necessities of all life-forms on the Earth. The  biotic  component incorporates all living of the biosphere. human sperm cells The abiotic component incorporates the air, the water, and the soil of the biosphere. Biogeochemical Cycles Biogeochemical cycles explain a constant interaction between the biotic and abiotic components of the biosphere. Biogeochemical cycles are a dynamic phenomenon that helps to maintain the stability in the ecosystem. The significant biogeochemical cycles are − Water Cycle Carbon Cycle Nitrogen Cycle Oxygen Cycle Let’s discuss each of them in brief − Water Cycle The whole process, starting from the water evaporation, rainfall to flowing back into the sea via rivers, is known as the  water-cycle . water forming a circle As shown in the image given above, water cycle is a complex phenomenon. During the p...

Biology - Why do We Fall Ill Introduction Health means a state of mental, physical, and social well-being. The health of an organism largely depends on his/her surroundings or the environment. a sick man Major causes of poor health are - the garbage, which is thrown in an open area nearby residence or streets, or/and the open drain water lying stagnant around the residence area. The public cleanliness is the key of good health. Some diseases, last only for a short period of time, are known as  acute diseases . E.g. cold, fever, etc. The diseases that last for a long period of time, even as much as a lifetime, are known as  chronic diseases . E.g. asthma, osteoporosis, etc. Chronic diseases, normally, have very severe long-term effects on people’s health as compared to the acute diseases. Infectious Diseases When microbes are the immediate causes of a disease, it is known as  infectious diseases . Some of the major agents of infectious diseases are viruses, bacteria, fungi...

Microorganisms: Friend and Foe Introduction The living organisms (available around us), which we cannot see with our naked eyes, are known as  microorganisms  or  microbes . Microorganisms are classified into the following four major groups − Bacteria Fungi Protozoa Algae Viruses Viruses are also microscopic microorganism. Viruses get reproduced only inside the cells of the host organism, which may be a bacterium, plant, or animal. The common ailments, such as cold, influenza (flu), and coughs are caused by viruses. The serious diseases, such as polio and chicken pox are also caused by viruses. The diseases like dysentery and malaria are caused by protozoans. The diseases like typhoid and tuberculosis (TB) are caused by bacteria. The single celled microorganisms are known as bacteria, algae, and protozoa. The multicellular microorganisms are known as fungi and algae. The microorganism can survive in any type of environment ranging from ice cold to hot desert. Microorganis...

Biology - Respiration Introduction The food material, taken in during the process of nutrition, is used by cells and then they provide energy for various life processes. Some organisms use oxygen to break-down glucose completely into carbon dioxide and water, such processes normally take place in cytoplasm. The following diagram illustrates the whole process of break-down of glucose through various pathways − During cellular respiration, the energy released, is immediately used to synthesize a molecule known as  ATP . ATP is further used to fuel all other activities in the cell. However, in these processes, ATP is broken down and give rise to a fixed amount of energy. This energy usually drives the endothermic reactions taking place in the cell. Adenosine triphosphate or simply ATP is a small molecule used in cells as a coenzyme (see image given below). More often, ATP is referred as the  energy currency  for most of the cellular processes (especially intracellular energy...

 Life Processes Introduction The processes, which collectively perform the maintenance of our body system, are known as  life processes . The maintenance processes protect us from damage and break-down; however, to keep these maintenance processes working properly, we need to provide energy to them. Healthy food is the best source of such energy. Nutrition We need energy from outside in order to grow, develop, synthesize protein, and other substances. The ultimate source of energy is varieties of healthy foods. These foods provide us nutrition essential for our survival. Depending upon the sources, nutrition is categorized as Autotrophic Nutrition and Heterotrophic Nutrition. Autotrophic Nutrition The autotrophic nutrition is prepared through the process of photosynthesis. Photosynthesis is a process by which autotrophic organisms (green plants) take in substances from the outside and then convert them into stored forms of energy. During the process of photosynthesis, carbon d...

Heredity and Evolution Introduction evolution The principle of heredity determines the process by which traits and characteristics of an organism are reliably inherited. There are some organisms (especially plants) in which there are very less variations and sometimes difficult to establish the differences, but in some other organisms (especially human beings), there are comparatively greater variations. This is the reason that offspring do not look similar. Rules for the Inheritance of Traits – Mendel’s Contributions Johann Mendel is known as " father of modern genetics ." In human beings, the rules for inheritance of traits and characteristics are related to the fact that both the father and the mother equally contribute the genetic material to their child. Further, each trait of an offspring is usually influenced by both paternal and maternal DNA. Johann Mendel, who was an Austrian scientist, had experimented on peas and gave the “ laws of inheritance .” Mendel used a vari...

Reaching the Age of Adolescence Introduction girl smilling The phase of life, when the body undergoes radical changes, leading to reproductive maturity, is known as  adolescence . Adolescence normally begins around the age of 11 and lasts up to 18 or 19 years of the age. However, the phase of adolescence varies from person to person. Starting from thirteen (13) to nineteen (19), ‘teen’ is suffix and common in every number; therefore, adolescents are also known as ‘ teenagers .’ In girls, adolescence phase may begin one year or two years earlier than the boys. During the adolescence phase, the human body undergoes several changes, which are marked as the onset of  puberty . The most important change, which marks puberty, is that the boys and the girls become capable of reproduction. Puberty, however, ends when an adolescent phase attains reproductive maturity. Changes at Puberty The most conspicuous change during the puberty is the swift increase in height. In the beginning, gi...