5. What is the difference between. Answers: (i) BIT and BYTE: BIT: Short for binary digit, the smallest unit of information on a machine. A single bit can hold only one of two values: 0 or 1. More meaningful information is obtained by combining consecutive bits into larger units. For example, a byte is composed of 8 consecutive bits. BYTE: Abbreviation for binary term, a unit of storage capable of holding a single character. On almost all modern computers, a byte is equal to 8 bits. Large amounts of memory are indicated in terms of kilobytes (1,024 bytes), megabytes (1,048,576 bytes), and gigabytes (1,073,741,824 bytes). (ii) RAM and ROM: RAM: Pronounced ramm, acronym for random access memory, a type of computer memory that can be accessed randomly; that is, any byte of memory can be accessed without touching the preceding bytes. RAM is the most common type of memory found in computers and other devices, such as printers. ROM: Pronounced rahm, acronym for read-only memory, computer memory on which data has been prerecorded. Once data has been written onto a ROM chip, it cannot be removed and can only be read. Unlike main memory (RAM), ROM retains its contents even when the computer is turned off. ROM is referred to as being nonvolatile, whereas RAM is volatile. Most personal computers contain a small amount of ROM that stores critical programs such as the program that boots the computer. In addition, ROMs are used extensively in calculators and peripheral devices such as laser printers, whose fonts are often stored in ROMs. In common usage, the term RAM is synonymous with main memory, the memory available to programs. For example, a computer with 8MB RAM has approximately 8 million bytes of memory that programs can use. In contrast, ROM (read-only memory) refers to special memory used to store programs that boot the computer and perform diagnostics. Most personal computers have a small amount of ROM (a few thousand bytes). In fact, both types of memory (ROM and RAM) allow random access. To be precise, therefore, RAM should be referred to as read/write RAM and ROM as read-only RAM. (iii) C.U. and A.L.U: CU: Short for control unit, it is a typical component of the CPU that implements the microprocessor instruction set. It extracts instructions from memory and decodes and executes them, and sends the necessary signals to the ALU to perform the operation needed. Control Units are either hardwired (instruction register is hardwired to rest of the microprocessor) or micro-programmed. ALU: Abbreviation of arithmetic logic unit, the part of a computer that performs all arithmetic computations, such as addition and multiplication, and all comparison operations. The ALU is one component of the CPU (central processing unit). (iv) Hardware and Software: Hardware: Refers to objects that you can actually touch, like disks, disk drives, display screens, keyboards, printers, boards, and chips. In contrast, software is untouchable. Software exists as ideas, concepts, and symbols, but it has no substance. Books provide a useful analogy. The pages and the ink are the hardware, while the words, sentences, paragraphs, and the overall meaning are the software. A computer without software is like a book full of blank pages -- you need software to make the computer useful just as you need words to make a book meaningful. Software: Computer instructions or data. Anything that can be stored electronically is software. The storage devices and display devices are hardware. The terms software and hardware are used as both nouns and adjectives. For example, you can say: "The problem lies in the software," meaning that there is a problem with the program or data, not with the computer itself. You can also say: "It's a software problem." (v) Personal computer and mainframe: Personal Computer (PC): Short for personal computer or IBM PC. The first personal computer produced by IBM was called the PC, and increasingly the term PC came to mean IBM or IBM-compatible personal computers, to the exclusion of other types of personal computers, such as Macintoshes. In recent years, the term PC has become more and more difficult to pin down. In general, though, it applies to any personal computer based on an Intel microprocessor, or on an Intel-compatible microprocessor. For nearly every other component, including the operating system, there are several options, all of which fall under the rubric of PC . Mainframe Computer: A very large and expensive computer capable of supporting hundreds, or even thousands, of users simultaneously. In the hierarchy that starts with a simple microprocessor (in watches, for example) at the bottom and moves to supercomputers at the top, mainframes are just below supercomputers. In some ways, mainframes are more powerful than supercomputers because they support more simultaneous programs. But supercomputers can execute a single program faster than a mainframe. The distinction between small mainframes and minicomputers is vague, depending really on how the manufacturer wants to market its machines. 6. Explain any five of the following terms (in not more than four lines each): Answers: (i) Osmosis: osmosis, in botany and chemistry, the flow of one constituent of a solution through a membrane while the other constituents are blocked and unable to pass through the (selecyively permeable membrane)membrane. experimentation is necessary to determine which membranes permit selective flow, or osmosis, because not all membranes act in this way. many membranes allow all or none of the constituents of a solution to pass through; only a few allow a selective flow. Glycolysis: Glycolysis, chemical process in which glucose is broken down, or catabolized, into the simpler sugar lactic acid, and energy is released. (ii) Phototaxis: movement of organism caused by light: movement of an organism either toward or away from a source of light . Phototaxis is called positive if the movement is in the direction of light and negative if the direction is opposite. (iii) Transpiration: Transpiration, evaporation of water particles from plant surfaces, especially from the surface openings, or stomata, on leaves . Stomatal transpiration accounts for most of the water loss by a plant, but some direct evaporation also takes place through the surfaces of the epidermal cells of the leaves. (iv) Saponification: Saponification is the hydrolysis of an ester under basic conditions to form an alcohol and the salt of a carboxylic acid (carboxylates). Saponification is commonly used to refer to the reaction of a metallic alkali (base) with a fat or oil to form soap. Saponifiable substances are those that can be converted into soap. Sodium hydroxide (NaOH) is a caustic base. If NaOH is used a hard soap is formed, whereas when potassium hydroxide (KOH) is used, a soft soap is formed. Vegetable oils and animal fats are fatty esters in the form of triglycerides. The alkali breaks the ester bond and releases the fatty acid salt and glycerol. If necessary, soaps may be precipitated by salting it out with saturated sodium chloride. The saponification value is the amount of base required to saponify a fat sample. (v) Emulsion: A suspension of small globules of one liquid in a second liquid with which the first will not mix: an emulsion of oil in vinegar 7. Fill in the blanks: (i) A sheet of muscles called diaphragm separates the chest from the abdomen. (ii) In the human body, blood-clotting factor is produced by the liver. (iii) Human blood is able to carry large amounts of oxygen because of the chemical hemoglobin. (iv) The living part of a plant cell is composed of a nucleus and cytoplasm. (v) The pattern for building protein molecules is stored in the messenger RNA. (vi) Anvil and stirrup are names of bones present in the ear. (vii) The front of the eye is covered with a tough transparent material called cornea. (viii) The young plant inside a grain of wheat is called the embryo plant. (ix) In born behaviour that involve only one part of the body are called reflex action. (x) The smallest branches of an artery lead into tiny blood vessels called capillaries. 8. What are Exocrine glands? Give names of any four along with the name of their secretion. Answer: Glands are of two principal types: (1) those of internal secretion, called endocrine, and (2) those of external secretion, called exocrine. Some glands such as the pancreas produce both internal and external secretions. Because endocrine glands produce and release hormones directly into the bloodstream without passing through a canal, they are called ductless. For the functions and diseases of endocrine glands, see Endocrine System. Sweat gland..............Sweat Sebaceous gland........Sebum Lacrimal gland ...........Tears Salivary gland.............Saliva 9. Which quantity do the following units measure:
(i) Volt (ii) Coulomb (iii) Walt (iv) Ohm (v) Mho (vi) Ampere (vii) Dyne (viii) Celsius (ix) Joule (x) Calorie (i) Voltage (ii) Charge of Electricity (iii) Power (iv) Resistance (v) Conductivity (vi) Current (vii) Force (viii) Temperature (ix) Energy (x) Heat 10. Give scientific reasons (in not more than four lines each) for the following: Answers: (i) Meat takes longer to cook on the mountains: The atmospheric pressure decreases as the altitude increases. The boiling point of water is 100 c at standard atmospheric pressure. At the mountains this atmospheric pressure is less, thus water boils at temperature lower than 100c.Therefore the meat takes longer time to be cooked. This can be overcome by using pressure cookers. (ii) Water remains cool in earthen pitchers: The water gets evaporated through the pores of earthen pot and in so doing takes more heat from the water in the form of latent heat and gets cooled in turn. While a metal or glass container has no pores and therefore does not permit the evaporation of water which does not get so cooled. (iii) Ice and salt mixture is used as a freezing agent by manual ice cream makers. Salt lowers down the temperature of ice by decreasing its freezing point. That is why ice and salt mixture is used as freezing agent in ice cream making. (iv) It is not advisable to sleep under trees during the night. Because plants at night releases carbon dioxide and takes up oxygen. (v) Greenhouse operators paint their glass roofs white in summer. In summer there is already much hot and white colour has a property of reflection of light to a maximum. And therefore white colour is painted on the roofs in the summer. 11. Which part/organ of the human body do the following belong: Answers: (i) Eustachian tube...... Ear (ii) Cartilage............... Connective tissue (iii) Auricle................. Ear (iv) Tendon ................Muscle (v) Dendrites.............. Neuron 12.Briefly describe the solar system. Name its members outlines the main characteristics of any two members. 13. Fill in the blanks. (i) Insulin is produced in the human body by the ___________. (Liver, Pancreas, Gallbladder) (ii) In an animal cell protein is synthesized in the ___________. (Nucleus, Mitochondria, Ribosome) (iii) Chemically finger nails are made up of ___________. (Carbohydrate, Protein, Minerals) (iv) Muscle stiffness is a symptom caused by the disease ___________ (Polio, Tetanus, Rabies) (v) Animals which obtain their food from dead organisms are called ___________. (Carnivores, Scavengers, Saprophytes) (vi) ___________ is not affected by cooking. (Ascorbic acid, Thiamin, Riboflavin) (vii) Rickets is caused by the deficiency of vitamin ___________. (A, D, K) (viii) The number of chromosomes in the spermatozoa is ___________ (Twenty-two,twenty-three, Forty-six) (ix) The fat in our food is digested by the enzymes ___________. (lipase, lactase, trypsin) (x) The most abundant element in the human body is ___________. (Carbon, Hydrogen,Oxygen) 14. Which of the following statements are false and which are true. (i) Sound is a form of energy. True (ii) A fraction of sunlight is refracted as it enters the earth’s atmosphere. True (iii) The energy possessed by a water fall is kinetic energy. False (iv) Rainbows are produced by the reflection of light through raindrops. False (v) Light switches in our homes are connected in parallel series. True (vi) Generators convert mechanical energy into electricity. True (vii) Modern incandescent bulbs contain filaments made of copper. False (viii) A steam engine cannot be powered by fossil fuels. False (ix) Nuclear energy is a cheap source of abundant electricity. True (x) Oil burns cleaner and is less damaging to the environment than coal as a fuel. True 15. Match words of List A with those of List B. Answers: ...A..............................B Protein.....................Amino acid Magnesium................Chlorophyll Carotene..................Vitamin A Bauxite....................Aluminium Haemitite.................Iron Casein.....................Milk Pancreas.................FATS Quartz....................Silicon Chlorofluorocarbon....Ozone Urea.......................Nitrogen ~~~~~~~~~******~~~~~~~~~
Note: Attempt TEN questions. All questions carry equal marks. 1. “Earthquakes have helped a great deal in deciphering the internal structure of the earth”. Comment on this statement. 2. Discuss briefly the achievements of Muslims in the development of science. State the reasons of downfall of science in Muslim Society. 3. Discuss in detail the fission and fusion processes. Which one of thee processes in the source of solar energy? 4. Give a detailed description of global warming and its possible effects on life. What measures have been taken by various nations to tackle this problem? 5. Give chemical name of one Nitrogenous and one Phosphorus containing fertilizer. What is the role of Nitrogen, Phosphorous and Potash in the growth and development of various parts of a plant. 6. Write short notes on the following: (i) Conductor (ii) Resistor (iii) Semi-conductor (iv) Thermistor (v) Transistor 7. Write short notes on five of the following: (i) Antibody (ii) Blood group (iii) Carbon cycle (iv) Nitrogen cycle (v) Scavenger (vi) Reaction time (vii) Photosynthesis (viii) Starfish 8.Which of the following statements are true? (i) Trout is a sea fish. False (ii) Epiphytes is a plant that grows upon another plant. True (iii) Hepatitis is inflammation of membranes surrounding the brain. False (iv) Meningitis is the inflammation of liver.False (v) Equinox is the time when the sun appears vertically overhead at noon at the equator. True (vi) Drought is a long period of rain. False (vii) Joseph Aspdin is the inventor of cement. True (viii) Neurology is the science of nervous system. True (ix) Biochemistry is the application of statistics in the study of Biology. True (x) Aviculture is the science of the rearing of animals. False 9. Name the quantities which are measured by the following units.
(i) Newton (ii) Joule (iii) Watt (iv) Volt (v) Light year (vi) Angstrom (vii) Acre-foot (viii) Becquerel (ix) Hertz (x) Cusec (i) Force (ii) Work Energy (iii) Power of electricity (iv) Potential difference (v) Distance of stars and planets (vi) Length (vii) Volume (viii) Radioactivity (ix) Frequency (x) Rate of flow of water 10. Match the cause of the disease: Answers: Disease-----Cause Rickets -------Deficiency of vitamin D Plasmodium ---Malaria Goiter---------Iodine deficiency Typhoid------ Salmonella typhosa Merismis ------Protein deficiency 11. What is the function of each of the following in a motor car: (i) Gear box (ii) Battery (iii) Carburetor (iv) Dynamo (v) Radiator 12. Explain the following: Answers: (i) Blood group A blood type (also called a blood group) is a classification of blood based on the presence or absence of inherited antigenic substances on the surface of red blood cells (RBCs). These antigens may be proteins, carbohydrates, glycoproteins or glycolipids, depending on the blood group system, and some of these antigens are also present on the surface of other types of cells of various tissues. Several of these red blood cell surface antigens, that stem from one allele (or very closely linked genes), collectively form a blood group system. (ii) Short circuit: 1) An electrical circuit of lower than usual resistance, especially one formed unintentionally. 2) A short circuit (sometimes abbreviated to short or s/c) allows a charge to flow along a different path from the one intended. The electrical opposite of a short circuit is an open circuit, which is infinite resistance between two nodes. It is common to misuse "short circuit" to describe any electrical malfunction, regardless of the actual problem. (iii) Short sight: the inability to see things clearly unless they are relatively close to the eyes; myopia. Detail: Short-sightedness, is a refractive defect of the eye in which collimated light produces image focus in front of the retina when accommodation is relaxed. Those with myopia see nearby objects clearly but distant objects appear blurred. With myopia, the eyeball is too long, or the cornea is too steep, so images are focused in the vitreous inside the eye rather than on the retina at the back of the eye. The opposite defect of myopia is hyperopia or "farsightedness" or "long-sightedness" — this is where the cornea is too flat or the eye is too short. (iv) International date line: Longitude line located at 180 degrees, longitude line that divides time zones so that one side is one one calendar day and the other side is on the next calendar day (v) Plaster of Paris: Plaster of Paris, or simply plaster, is a type of building material based on calcium sulfate hemihydrate, nominally CaSO4•0.5H2O. It is created by heating gypsum to about 150 °C. 13. Answer the following: (i) Of what lead pencils are made of? (ii) Why is one’s breath visible in cold but not in hot weather? (iii) What is the chemical composition of diamond? (iv) Name the vaccine that protects against tuberculosis. (v) Name the disease of the liver that causes a patient to turn yellow. 14. Fill in the blanks. (i) Black hole is a hypothetical region of space having a gravitational pull so great that no matter or radiation can escape from it. (ii) Fungicides are used against mould and fungi. (iii) The science which deals with heredity is known as genetics. (iv) Insulin is used for the treatment of diabetes. (v) Yuri Gagarin is the first space man. (vi) Pluto is the farthest planet from the sun in Solar System. (vii) The distance between the earth and the sun is called Astronomoical Unit. (viii) The study of chemical processes of living organisms is called biochemistry. (ix) The first computer virus invented by two Pakistani brothers is called the brain. (x) Severe efficiency of vitamin C results in scurvy. 15. Differentiate between any five of the following. Answers: (i) Artery and vein: Arteries: Muscular blood vessels that carry blood away from the heart. All arteries, with the exception of the pulmonary and umbilical arteries, carry oxygenated blood. Vein: A blood vessel that carries blood toward the heart. The majority of veins in the body carry low-oxygen blood from the tissues back to the heart; the exceptions being the pulmonary and umbilical veins which both carry oxygenated blood. (ii) Hard water and soft water: Hard water: Water that has a high mineral content (contrast with soft water), usually consisting of calcium (Ca2+) and magnesium (Mg2+) ions, and possibly including other dissolved metals, bicarbonates, and sulfates. Calcium usually enters the water as either calcium carbonate (CaCO3) in the form of limestone and chalk, or calcium sulfate (CaSO4) in the form of other mineral deposits. The predominant source of magnesium is dolomite (CaMg(CO3)2). Hard water is generally not harmful. Soft water: The term used to describe types of water that contain few or no calcium or magnesium ions. The term is usually relative to hard water, which does contain significant amounts of such ions. (iii) E-mail and Snail mail: E-Mail: Method of correspondence via the Internet; communication sent by electronic mail. Snail Mail: Regular mail, normal postal service (not electronic mail) (iv) Apes and monkey: A monkey is any member of either the New World monkeys or Old World monkeys, two of the three groupings of simian primates, the third group being the apes. (v) Hydrostatics and hydrodynamics: Hydrostatics: Fluid statics (also called hydrostatics) is the science of fluids at rest, and is a sub-field within fluid mechanics Hydrodynamics: The branch of science concerned with forces acting on or exerted by fluids (especially liquids). (vi) Comet and meteor: Comet: Any icy object that exists within the solar system. They are pieces of the primitive, unprocessed matter that formed the solar system 4.6 x 109 years ago. They are typically a few kilometers across and consist mainly of dust grains, frozen water, carbon monoxide and carbon dioxide; they contain many simple organic molecules. Meteor: A meteoroid is a small sand to boulder-sized particle of debris in the Solar system. The visible path of a meteoroid that enters Earth's (or another body's) atmosphere is a meteor, commonly called a "shooting star" or "falling star". Many meteors are part of a meteor shower. (vii) Barrage and dam: Barrage: Not built at heights. Pressure is not enough to produce electricity. Only Canals are marked out of it. Dam: Built at heights. Pressure is enough to move turbines so hydroelectricity is generated. (viii) Electron and hole: Electron: They belong to the lepton family and are the negatively charged components of atoms (1.6 x10^-19 coulomb). In the simplest model of the atom, electrons are envisaged to move around the atomic nucleus in specified circular and elliptical orbits. Electron Hole: An electron hole is the conceptual and mathematical opposite of an electron, useful in the study of physics and chemistry. The concept describes the lack of an electron. It is different from the positron, which is the antimatter duplicate of the electron. (ix) Isobars and isotopes: Isobars: line on a weather map or chart that connects areas of equal barometric pressure Isotopes: Any of the several different forms of an element each having different atomic mass (mass number). Isotopes of an element have nuclei with the same number of protons (the same atomic number) but different numbers of neutrons. Or Isotopes and Isobars: The various nuclides, or species, of a particular chemical element with equal proton number (atomic number), but different neutron numbers were called isotopes of the element, before the more inclusive term "nuclide" was internationally accepted (ca. 1950. Such particular nuclides may still be called "isotopes." However, nuclides with equal mass number but different atomic number are called isobars (isobar = equal in weight), whereas Isotones are nuclides of equal neutron number but different proton numbers. (x)Autopsy and biopsy: Autopsy: Postmortem, examination of a corpse to determine cause of death Biopsy: Removal and study of a tissue sample for diagnostic purposes ~~~~~~~~~******~~~~~~~~~
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