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Poultry   Poultry includes the birds like chicken (hen), ducks, geese and turkey. Poultry farming deals with the rearing of them for their eggs and meat. Fowls are widely distributed as domesticated animal since time immemorial, but in the present century, it has become an important small scale industry due to modern need for palatable and nutritive food which it provides in the form of eggs as well as adult animal. An egg laying poultry bird is called hen and the poultry birds groomed for obtaining meat are called chicken or broilers. Birds especially chicken grown for meat only is known as Broiler Poultry is closely related to the problems of nutrition. Poultry and poultry products like eggs are a rich source of animal protein and a right kind of fat for good health. India and the neighboring countries, like Burma, Sri Lanka are the original home of the red jungle fowl (Gallus gallus). It seems that Aseel or Malay fowl were carried to Europe through the Middle East about 2,000 years ago and have given rise to the present-day European breeds.   (i) Poultry farming v/s livestock rearing : Poultry birds are easy to raise, can be acclimatised to a wide range of climatic conditions, have short life span and are prolific breeders and thus poultry farming is advantageous over livestock rearing. Moreover, poultry farming requires less space and easy to manage and maintain and brings fast returns. Hens have an average yield of 60 eggs per year, but high yielding varieties can produce more than 240 eggs in a year. Poultry contributes about Rs. 7,500 crores to the gross national product (GNP) of India. India ranks fifth in the world's egg production. Egg is one such food commodity which cannot be adulterated. The average per capita consumption is about 32 eggs and 600 grams of poultry meat a year. At present poultry is estimated to provide employment to about seven lakh families.   (ii) Raising of poultry - Fowl house: Fowls can be reared in the hills of India without houses, but in the plains, well- ventilated and illuminated, dry houses are essential. A house of  has sufficient accommodation for six fowls. An open shed or verandah must be attached to this house as run to the fowls for exercise. The fowl house may be either of wood or brick and the roof is made up of corrugated iron sheets, thatch or wood. The floor is littered with chopped straw, paddy husk, dry leaves or groundnut hulls. The fowl house must be rat- proof, with proper drainage. The house and shed should be cleaned daily. Fowls of different ages are kept in separate houses. In regions with moderate climate, they are kept in cages (coops).   (a) Feed: The quality and balanced quantity of food material are the back-bones of poultry. The feed given to poultry birds should contain all the essential nutrients like carbohydrates, fats, proteins, minerals and vitamins. The feed usually consists more...

Anaerobic Respiration   Anaerobic respiration first studied by Kostychev (1902), Anaerobic respiration is an enzyme-controlled, partial break down of organic compounds (food) without using oxygen and releasing only a fraction of the energy. It is also called intra-molecular respiration (Pfluger, 1875). Anaerobic respiration occurs in the roots of some water-logged plants, certain parasitic worms (Ascaris and Taenia), animal muscle and some microorganisms (bacteria, moulds). In microorganisms anaerobic respiration is often called fermentation. Higher organism like plants cannot perform anaerobic respiration for long. It is toxic because accumulation of end products, insufficient amount of available energy and causes stoppage of many active process. (1) Process of anaerobic respiration : In this process pyruvate which is formed by glycolysis is metabolised into ethyl alcohol or lactic acid and \[C{{O}_{2}}\]in the absence of oxygen. Glycolysis is occurs in cytoplasm so the site of anaerobic respiration is cytoplasm. \[{{C}_{6}}{{H}_{12}}{{O}_{6}}2{{C}_{2}}{{H}_{5}}OH+\text{ }2C{{O}_{2}}+\text{ }52\text{ }Kcal/218.4kJ\] (i) Formation of ethyl alcohol :  When oxygen is not available, yeast and some other microbes convert pyruvic acid into ethyl alcohol. This is two step process as explained below                (a) In the first step pyruvic acid is decarboxylated to yield acetaldehyde and \[C{{O}_{2}}\]. In the presence of Mg++ and TPP (Thiamine pyrophosphate) pyruvate carboxylase. \[\underset{(\text{Pyruvic}\,\text{acid})}{\mathop{C{{H}_{3}}COCOOH}}\,\underset{\begin{smallmatrix}  \text{Carboxylase} \\  M{{g}^{2+}}+TPP \end{smallmatrix}}{\mathop{\xrightarrow{\text{Pyruvic}}}}\,\underset{(\text{Acetaldehyde})}{\mathop{C{{H}_{3}}CHO}}\,+C{{O}_{2}}\] (b) In the second step acetaldehyde is reduced to ethyl alcohol by NADH2 formed in the glycolysis. \[\underset{(\text{Acetaldehyde})}{\mathop{C{{H}_{3}}CHO}}\,+NAD{{H}_{2}}\underset{\text{dehydrogenase}}{\mathop{\xrightarrow{\text{Alcoholic}}}}\,\underset{(\text{Ethyl}\,\text{alcohol})}{\mathop{{{C}_{2}}{{H}_{5}}OH}}\,+NAD\] (ii) Production of lactic acid : In this process hydrogen atoms removed from the glucose molecule during glycolysis are added to pyruvic acid molecule and thus lactic acid is formed. \[\underset{\text{(Pyruvic acid)}}{\mathop{C{{H}_{3}}COCOOH}}\,\to \underset{\text{(Lactic acid)}}{\mathop{C{{H}_{3}}CHOH.COOH}}\,+NAD\] Lactic acid is produced in the muscle cells of human beings and other animals. During strenuous physical activity such as running, the amount of oxygen delivered to the muscle cells may be insufficient to keep pace with that of cellular respiration. Under such circumstances lactic acid is formed which accumulates in the muscle cells and causes muscle fatigue.   (2) Pasteur effect : Two types of respiration -anaerobic and aerobic respiration produce carbon dioxide in the ratio of 1:3 as shown in the equation. Anaerobic Respiration : \[\underset{(\text{Two}\,\text{molecules}\,\text{of}\,\,C{{O}_{2}}\,\text{are}\,\text{produced})}{\mathop{{{C}_{6}}{{H}_{12}}{{O}_{6}}\to 2{{C}_{2}}{{H}_{5}}OH+2C{{O}_{2}}}}\,\] Aerobic Respiration : \[\underset{(\text{Six}\,\text{molecules}\,\text{of}\,C{{O}_{2}}\,\text{are}\,\text{produced})}{\mathop{{{C}_{6}}{{H}_{12}}{{O}_{4}}+6{{O}_{2}}\to 6{{H}_{2}}O+6C{{O}_{2}}}}\,\] Pasteur noted that when oxygen is given to the running anaerobic respiration the output of CO2 is not similar to aerobic respiration, i.e. during aerobic respiration the ratio 1:3 does not always appear to be true. In several cases the amount of carbon dioxide is much less in comparison to normal aerobic respiration as shown above. For such cases it is considered that the presence of oxygen may sometimes lower down the rate of breakdown of sugar. The phenomenon is named as 'Pasteur's effects' after the name of great scientist and the process may be defined as "the inhibition of sugar breakdown due to the presence of oxygen under aerobic condition" and the reaction is called Pasteur reaction. Dixon (1937) stated that the Pasteur effect is the action of oxygen is more...

Introduction   All organisms require continuous input of energy to carry on life process. These energy comes from cellular activities. All the cellular activities can be grouped into two categories: anabolism (biosynthetic activities of the cell) and catabolism (breaking- up process of the cell). The anabolic activities are endergonic (utilizes energy in cellular activities), while the catabolic activities are usually exergonic (energy releasing process by oxidation of food material). The sum of total catabolic and anabolic reactions occurring at any time in a cell is called metabolism.   Respiration is a vital process, includes the intake of oxygen. Chemically it is catabolic and brings about the oxidation and decomposition of organic compounds like carbohydrate, fat, protein in the cells of plants and animals with the release of energy. Oxidation of organic compounds by respiration, resulting in the release of chemical energies water and carbon dioxide. The overall process may be states according to the following general equation: \[\underset{\text{glucose}}{\mathop{{{C}_{6}}{{H}_{12}}{{O}_{6}}}}\,+6C{{O}_{2}}\xrightarrow{\text{enzymes}}\underset{\text{carbondioxide}}{\mathop{6C{{O}_{2}}}}\,+\underset{\text{Water}}{\mathop{6{{H}_{2}}O}}\,+\underset{\text{(ATP)}}{\mathop{energy}}\,\] In this reaction, six molecules of oxygen taken up and six molecules each of \[C{{O}_{2}}and\text{ }{{H}_{2}}O\]are formed with energy derived from respiration of each molecule of sugar oxidation. The plant cell is able to do chemical work in synthesizing energy- rich materials such as fat and hydrocarbon, osmotic work such as uptake and accumulation of salt and mechanical work such as involved in growth.   Respiration   Definition of respiration : Cellular respiration is an enzyme controlled process of biological oxidation of food materials in a living cell, using molecular\[{{O}_{2}}\], producing\[C{{O}_{2}}and\text{ }{{H}_{2}}O\], and releasing energy in small steps and storing it in biologically useful forms, generally  ATP.   (1) Use of energy : Cellular activities like active transport, muscle-contraction, bioluminescenes, homothermy locomotion, nerve impulse conduction, cell division, growth, development, seed germination require energy. Main source of energy for these endergonic activities in all living organisms including plants, comes from the oxidation of organic molecules.     The energy released by oxidation of organic molecules is actually transferred to the high energy terminal bonds of ATP, a form that can be readily utilized by the cell to do work. Once ATP is formed, its energy may be utilized at various places in the cell to drive energy- requiring reactions. In these processes, one of the three phosphate groups is removed from the ATP molecule. Thus the role of ATP as an intermediate energy transforming compound between energy releasing and energy consuming reactions.             (2) Significance of respiration: Respiration plays a significant role in the life of plants. The important ones are given below: (i) It releases energy, which is consumed in various metabolic process necessary for life of plant. (ii) Energy produced can be regulated according to requirement of all activities. (iii) It convert in soluble foods into soluble form. (iv) Intermediate products of cell respiration can be used in different metabolic pathways e.g. Acetyl- CoA (in the formation of fatty acid, cutin and isoprenoids) ; \[\alpha \]- ketoglutaric acid (in more...

A branch of science which deals with the measurement of temperature of a substance is known as thermometry. (1) The linear variation in some physical properties of a substance with change of temperature is the basic principle of thermometry and these properties are defined as thermometric property \[(x)\] of the substance. (2) Thermometric properties \[(x)\] may be as follows (i) Length of liquid in capillary (ii) Pressure of gas at constant volume. (iii) Volume of gas at constant pressure. (iv) Resistance of a given platinum wire. (3) In old thermometry, freezing point \[({{0}^{o}}C)\] and steam point \[({{100}^{o}}C)\] are taken to define the temperature scale. So if the thermometric property at temperature \[{{0}^{o}}C,\,{{100}^{o}}C\] and \[{{t}^{o}}C\] are \[{{x}_{0}},\,{{x}_{100}}\] and \[x\] respectively then \[\frac{t-0}{100-0}=\frac{x-{{x}_{0}}}{{{x}_{100}}-{{x}_{0}}}\] Þ \[t{}^\circ C=\frac{x-{{x}_{0}}}{{{x}_{100}}-{{x}_{0}}}\times 100{}^\circ C\] (4) In modern thermometry instead of two fixed points only one reference point is chosen (triple point of water 273.16 K) the other is itself 0 K where the value of thermometric property is assumed to be zero. So if the value of thermometric property at 0 K, 273.16 K and TK are \[0,\,\,{{x}_{Tr}}\] and \[x\] respectively then \[\frac{T}{273.16}=\frac{x}{{{x}_{Tr}}}\]  \[\Rightarrow \] \[T=273.16\,\left[ \frac{x}{{{x}_{Tr}}} \right]\,K\]  

Electrovalent Bonding Atoms of different elements excepting noble gases don?t have complete octet so they combine with other atoms to form chemical bond. The force which holds the atoms or ions together within the molecule is called a chemical bond and the process of their combination is called Chemical Bonding.             Chemical bonding depends on the valency of atoms. Valency was termed as the number of chemical bonds formed by an atom in a molecule or number of electrons present in outermost shell i.e., valence electrons. Valence electrons actually involved in bond formation are called bonding electrons. The remaining valence electrons still available for bond formation are referred to as non-bonding electrons.             Cause and Modes of chemical combination. Chemical combination takes place due to following reasons. (1) Chemical bonding takes place to acquire a state of minimum energy and maximum stability. (2) By formation of chemical bond, atoms convert into molecule to acquire stable configuration of the nearest noble gas. Modes: Chemical bonding can occur in the following manner. Electrovalent bond. When a bond is formed by complete transfer of electrons from one atom to another so as to complete their outermost orbits by acquiring 8 electrons (i.e., octet) or 2 electrons (i.e., duplet) in case of hydrogen, helium etc. and hence acquire the stable nearest noble gas configuration, the bond formed is called ionic bond,  electrovalent bond or polar bond. Compounds containing ionic bond are called ionic, electrovalent or polar compounds. Example: Some other examples are: \[MgC{{l}_{2}},\text{ }CaC{{l}_{2}},\text{ }MgO,\text{ }N{{a}_{2}}S,\text{ }Ca{{H}_{2}},\text{ }Al{{F}_{3}},\text{ }NaH,\text{ }KH,{{K}_{2}}O,\text{ }KI,\text{ }RbCl,\text{ }NaBr,\text{ }Ca{{H}_{2}}\] etc. (1) Conditions for formation of electrovalent bond (i) Number of valency electrons : The atom which changes into cation (+ ive ion) should possess 1, 2 or 3 valency electrons. The other atom which changes into anion (- ive ion) should possess 5, 6 or 7 electrons in the valency shell. (ii) Electronegativity difference: A high difference of electronegativity (about 2) of the two atoms is necessary for the formation of an electrovalent bond. Electrovalent bond is not possible between similar atoms. (iii) Small decrease in energy: There must be overall decrease in energy i.e., energy must be released. For this an atom should have low value of Ionisation potential and the other atom should have high value of electron affinity. (iv) Lattice energy: Higher the lattice energy, greater will be the ease of forming an ionic compound. The amount of energy released when free ions combine together to form one mole of a crystal is called lattice energy (U). Magnitude of lattice energy \[\propto \frac{\text{Charge of ion}}{\text{size}\ \text{of}\ \text{ion}}\] \[{{A}^{+}}(g)+{{B}^{-}}(g)\xrightarrow{{}}AB(s)+U\] Determination of lattice energy (Born Haber cycle) When a chemical bond is formed between two atoms (or ions), the potential energy of the system constituting the two atoms or ions decreases. If there is no fall in potential energy of the system, no bonding more...