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Q.2. (a) Fission & Fusion
Nuclear Fission: A nuclear reaction in which an atomic nucleus, especially a heavy nucleus such as an isotope of uranium, splits into fragments, usually two fragments of comparable mass, releasing from 100 million to several hundred million electron volts of energy.
235U + 1 neutron 2 neutrons + 92Kr + 142Ba + ENERGY
Nuclear Fusion: Nuclear fusion is the process by which two light atomic nuclei combine to form one heavier atomic nucleus. As an example, a proton (the nucleus of a hydrogen atom) and a neutron will, under the proper circumstances, combine to form a deuteron (the nucleus of an atom of "heavy" hydrogen).


Q.2. (b)Star & Planet
Star: A self-luminous body that during its life generates (or will generate) energy and support by thermonuclear fusion.
Explanation: Any massive celestial body of gas that shines by radiant energy generated inside it. The Milky Way Galaxy contains hundreds of billions of stars; only a very small fraction are visible to the unaided eye. The closest star to Earth is the Sun. The closest star to the Sun is about 4.2 light-years away; the most distant are in galaxies billions of light-years away. Single stars such as the Sun are the minority; most stars occur in pairs and multiple systems (see binary star). Stars also associate by their mutual gravity in larger assemblages called clusters (see globular cluster; open cluster). Constellations consist not of such groupings but of stars in the same direction as seen from Earth. Stars vary greatly in brightness (magnitude), colour, temperature, mass, size, chemical composition, and age. In nearly all, hydrogen is the most abundant element. Stars are classified by their spectra (see spectrum), from blue-white to red, as O, B, A, F, G, K, or M; the Sun is a spectral type G star. Generalizations on the nature and evolution of stars can be made from correlations between certain properties and from statistical results (see Hertzsprung-Russell diagram). A star forms when a portion of a dense interstellar cloud of hydrogen and dust grains collapses from its own gravity. As the cloud condenses, its density and internal temperature increase until it is hot enough to trigger nuclear fusion in its core (if not, it becomes a brown dwarf). After hydrogen is exhausted in the core from nuclear burning, the core shrinks and heats up while the star's outer layers expand significantly and cool, and the star becomes a red giant.
Planet: A relatively small, solid celestial body moving in orbit around a star, in particular the Sun.
Explanation: According to the IAU's current definitions, there are eight planets in the Solar System. In increasing distance from the Sun, they are:
1. Mercury
2. Venus
3. Earth
4. Mars
5. Jupiter
6. Saturn
7. Uranus
8. Neptune
Jupiter is the largest, at 318 Earth masses, while Mercury is smallest, at 0.055 Earth masses.
The planets of the Solar System can be divided into categories based on their composition:
• Terrestrials: Planets that are similar to Earth, with bodies largely composed of rock: Mercury, Venus, Earth and Mars.
• Gas giants: Planets with a composition largely made up of gaseous material and are significantly more massive than terrestrials: Jupiter, Saturn, Uranus, Neptune. Ice giants, comprising Uranus and Neptune, are a sub-class of gas giants, distinguished from gas giants by their significantly lower mass, and by depletion in hydrogen and helium in their atmospheres together with a significantly higher proportion of rock and ice.

Q.2. (c) Pollination & Fertilization
Transfer of pollen from the male reproductive organ (stamen) to the female reproductive organ (pistil) of the same or of another flower or cone. Pollination is not to be confused with fertilization, which it may precede by some time—a full season in many conifers. The most common agents of pollination are flying insects (as in most flowering plants) and the wind (as in many trees and all grasses and conifers), but crawling and hopping insects, snails, bats, primates, rodents, and hummingbirds may also serve.
The union of male and female gametes to form a zygote is known as fertilization.


Q.2. (d) Telescope & Microscope

A telescope is a device that collects light from and magnifies images of distant objects, undoubtedly the most important investigative tool in astronomy. A telescope is an instrument designed for the observation of remote objects and the collection of electromagnetic radiation.


A refracting telescope forms an image by focusing light from a distant objects.
Types of Telescopes:
(1) Optical Telescope: An optical telescope gathers and focuses light mainly from the visible part of the electromagnetic spectrum.
(2) Radio Telescope: Radio telescopes are directional radio antennas that often have a parabolic shape. Radio telescopes are also used to collect microwave radiation.
(3) X-ray and gamma-ray telescopes: X-ray and gamma-ray radiation go through most metals and glasses. Gamma-ray telescopes refrain from focusing completely and use coded aperture masks: the patterns of the shadow the mask creates can be reconstructed to form an image. These types of telescopes are usually on Earth-orbiting satellites or high-flying balloons since the Earth's atmosphere is opaque to this part of the electromagnetic spectrum.

Microscope: An instrument used to obtain an enlarged image of a small object. The image may be seen, photographed, or sensed by photocells or other receivers, depending upon the nature of the image and the use to be made of the information of the image.
(1) Simple Microscope: A simple microscope, hand lens, or magnifier usually is a round piece of transparent material, ground thinner at the edge than at the center, which can form an enlarged image of a small object. Commonly, simple microscopes are double convex or planoconvex lenses, or systems of lenses acting together to form the image.
(2) Compound Microscope: The compound microscope utilizes two lenses or lens systems. One lens system forms an enlarged image of the object and the second magnifies the image formed by the first. The total magnification is then the product of the magnifications of both lens systems (see illustration).

Compound microscope diagram. (After F. A. Jenkins and H. E. White, Fundamentals of Optics, 4th ed., McGraw-Hill, 1976)
The typical compound microscope consists of a stand, a stage to hold the specimen, a movable body-tube containing the two lens systems, and mechanical controls for easy movement of the body and the specimen. The lens system nearest the specimen is called the objective; the one nearest the eye is called the eyepiece or ocular. A mirror is placed under the stage to reflect light into the instrument when the illumination is not built into the stand. For objectives of higher numerical aperture than 0.4, a condenser is provided under the stage to increase the illumination of the specimen. Various optical and mechanical attachments may be added to facilitate the analysis of the information in the doubly enlarged image.




Q.2. (e) Antibiotics & Vaccines
Antibiotics: Substances produced by living organisms which inhibit the growth of other organisms. The first antibiotic to be discovered was penicillin, which is produced by the mould Penicillium notatum and inhibits the growth of sensitive bacteria. Many antibiotics are used to treat bacterial infections in human beings and animals; different compounds affect different bacteria.
Explanation: Antibiotics represent a class of drugs used in the treatment of infections and infectious diseases caused by bacteria. These bacteria possess unique features (e.g., a cell wall, proteins, enzymes) that differentiate them from animal cells. Antibiotics interfere with the production of these bacterial characteristics, resulting in selective killing or growth inhibition of susceptible microorganisms. For example, prior to 1990, infections caused by Streptococcus pneumoniae (e.g., pneumonia, bronchitis, ear infections), were usually treated with penicillin or amoxicillin. Streptococcus pneumoniae possess a cell wall that acts as a protective barrier— a unique feature not found on animal or human cells. Penicillin or amoxicillin, two common antibiotics, bind to that cell wall as it is produced, causing it to weaken and "leak," eventually killing the bacteria without harming the animal host cells.
Vaccines: A vaccine is a medical preparation given to a person to provide immunity from a disease.
Explanation: Vaccines use a variety of different substances ranging from dead microorganisms to genetically engineered antigens to defend the body against potentially harmful antigens. Effective vaccines change the immune system by promoting the development of antibodies that can quickly and effectively attack disease causing microorganisms or viruses when they enter the body, preventing disease development.
In 1961, an oral polio vaccine developed by Albert B. Sabin (1906–1993) was licensed in the United States.






Q.3. (a) Solar System

Definition: The Sun, its eight major planets, the dwarf planets and small bodies, and interplanetary dust and gas under the Sun's gravitational control. Or, the Sun and the bodies moving in orbit around it.
Another component of the solar system is the solar wind. The Sun contains more than 99% of the mass of the solar system; most of the rest is distributed among the planets, with Jupiter containing about 70%.
Explanation: The most massive body in the solar system is the Sun, a typical single star that is itself in orbit about the center of the Milky Way Galaxy. Nearly all of the other bodies in the solar system—the terrestrial planets, outer planets, asteroids, and comets—revolve on orbits about the Sun. Various types of satellites revolve around the planets; in addition, the giant planets all have orbiting rings. The orbits for the planets appear to be fairly stable over long time periods and hence have undergone little change since the formation of the solar system. It is thought that some 4.56 × 109 years ago a rotating cloud of gas and dust collapsed to form a flattened disk (the solar nebula) in which the Sun and other bodies formed. The bulk of the gas in the solar nebula moved inward to form the Sun, while the remaining gas and dust are thought to have formed all the other solar system bodies by accumulation proceeding through collisions of intermediate-sized bodies called planetesimals. Planetary systems are believed to exist around many other stars in the Milky Way Galaxy. Solid evidence for the existence of Jupiter-mass planets around nearby solarlike stars now exists.

Q.3. (b) Causes of Earthquakes
The short answer is that earthquakes are caused by faulting, a sudden lateral or vertical movement of rock along a rupture (break) surface.
However, the two main causes of eartquakes are as follows:
1- Explosive volcanic eruptions: they are in fact very common in areas of volcanic activity where they either proceed or accompany eruptions.
2- Tectonic activity: This activity is associated with plate margins and faults. The majority of earthquakes world wide are of this type.
Explanation: The earth is divided into three main layers - a hard outer crust, a soft middle layer and a center core. The outer crust is broken into massive, irregular pieces called "plates." These plates move very slowly, driven by energy forces deep within the earth. Earthquakes occur when these moving plates grind and scrape against each other.
Geologists and Geographers call the origin of the earthquake the focus. Since this is often deep below the surface and difficult to map, the location of the earthquake is often referred to as the point on the Earth surface directly above the focus. This point is called the epicentre.
Earthquake shockwaves and Types:
Earthquakes are three dimensional events, the waves move outwards from the focus, but can travel in both the horizontal and vertical plains. This produces three different types of waves which have their own distinct characteristics and can only move through certain layers within the Earth. Lets take a look at these three forms of shock waves.
Types of shockwaves:
1- P-Waves
Primary Waves (P-Waves) are identical in character to sound waves. They are high frequency, short-wavelength, longitudinal waves which can pass through both solids and liquids. The ground is forced to move forwards and backwards as it is compressed and decompressed. This produces relatively small displacements of the ground.
P Waves can be reflected and refracted, and under certain circumstances can change into S-Waves.

Particles are compressed and expanded in the wave's direction.
2- S-Waves
Secondary Waves (S-Waves) travel more slowly than P-Waves and arrive at any given point after the P-Waves. Like P-Waves they are high frequency, short-wavelength waves, but instead of being longitudinal they are transverse. They move in all directions away from their source, at speeds which depend upon the density of the rocks through which they are moving. They cannot move through liquids. On the surface of the Earth, S-Waves are responsible for the sideways displacement of walls and fences, leaving them 'S' shaped.

S-waves move particles at 90° to the wave's direction.
3- L-Waves
Surface Waves (L-Waves) are low frequency transverse vibrations with a long wavelength. They are created close to the epicentre and can only travel through the outer part of the crust. They are responsible for the majority of the building damage caused by earthquakes. This is because L Waves have a motion similar to that of waves in the sea. The ground is made to move in a circular motion, causing it to rise and fall as visible waves move across the ground. Together with secondary effects such as landslides, fires and tsunami these waves account for the loss of approximately 10,000 lives and over $100 million per year.

L-waves move particles in a circular path.
Types of Earthquakes:
1- Tectonic Earthquakes:
Tectonic earthquakes are triggered when the crust becomes subjected to strain, and eventually moves. The theory of plate tectonics explains how the crust of the Earth is made of several plates, large areas of crust which float on the Mantle. Since these plates are free to slowly move, they can either drift towards each other, away from each other or slide past each other. Many of the earthquakes which we feel are located in the areas where plates collide or try to slide past each other.
The process which explains these earthquakes, known as Elastic Rebound Theory can be demonstrated with a green twig or branch. Holding both ends, the twig can be slowly bent. As it is bent, energy is built up within it. A point will be reached where the twig suddenly snaps. At this moment the energy within the twig has exceeded the Elastic Limit of the twig. As it snaps the energy is released, causing the twig to vibrate and to produce sound waves.
Perhaps the most famous example of plates sliding past each other is the San Andreas Fault in California. Here, two plates, the Pacific Plate and the North American Plate, are both moving in a roughly northwesterly direction, but one is moving faster than the other. The San Francisco area is subjected to hundreds of small earthquakes every year as the two plates grind against each other. Occasionally, as in 1989, a much larger movement occurs, triggering a far more violent 'quake'.
Major earthquakes are sometimes preceded by a period of changed activity. This might take the form of more frequent minor shocks as the rocks begin to move,called foreshocks , or a period of less frequent shocks as the two rock masses temporarily 'stick' and become locked together. Detailed surveys in San Francisco have shown that railway lines, fences and other longitudinal features very slowly become deformed as the pressure builds up in the rocks, they become noticeably offset when a movement occurs along the fault. Following the main shock, there may be further movements, called aftershocks, which occur as the rock masses 'settle down' in their new positions. Such aftershocks cause problems for rescue services, bringing down buildings already weakened by the main earthquake.
2- Volcanic Earthquakes:
Volcanic earthquakes are far less common than Tectonic ones. They are triggered by the explosive eruption of a volcano. Given that not all volcanoes are prone to violent eruption, and that most are 'quiet' for the majority of the time, it is not surprising to find that they are comparatively rare.
When a volcano explodes, it is likely that the associated earthquake effects will be confined to an area 10 to 20 miles around its base, where as a tectonic earthquake may be felt around the globe.
The volcanoes which are most likely to explode violently are those which produce acidic lava. Acidic lava cools and sets very quickly upon contact with the air. This tends to chock the volcanic vent and block the further escape of pressure. For example, in the case of Mt Pelee, the lava solidified before it could flow down the sides of the volcano. Instead it formed a spine of solid rock within the volcano vent. The only way in which such a blockage can be removed is by the build up of pressure to the point at which the blockage is literally exploded out of the way. In reality, the weakest part of the volcano will be the part which gives way, sometimes leading to a sideways explosion as in the Mt St. Helens eruption.
When extraordinary levels of pressure develop, the resultant explosion can be devastating, producing an earthquake of considerable magnitude. When Krakatoa ( Indonesia, between Java and Sumatra ) exploded in 1883, the explosion was heard over 5000 km away in Australia. The shockwaves produced a series of tsunami ( large sea waves ), one of which was over 36m high; that's the same as four, two story houses stacked on top of each other. These swept over the coastal areas of Java and Sumatra killing over 36,000 people.
By contrast, volcanoes producing free flowing basic lava rarely cause earthquakes. The lava flows freely out of the vent and down the sides of the volcano, releasing pressure evenly and constantly. Since pressure doesn't build up, violent explosions do not occur.











Q.4. (a) Supernova
Definition: A large star in its death throes that suddenly explodes, increasing many thousands of times in brightness.
Explanation: Like novas, supernovas undergo a tremendous, rapid brightening lasting a few weeks, followed by a slow dimming, and show blue-shifted emission lines on spectroscopy, which implies that hot gases are blown outward. Unlike a nova, a supernova explosion is a catastrophic event for a star, leading to its collapse into a neutron star or black hole. Amounts of its matter equal to the mass of several Suns may be blasted into space with such energy that the exploding star outshines its entire home galaxy. Only seven supernovas are known to have been recorded before the 17th century, the most famous in AD 1054; its remnants are visible today as the Crab Nebula. The closest and most studied supernova in modern times is SN 1987A, which appeared in 1987 in the Large Magellanic Cloud. Supernova explosions release not only tremendous amounts of radio energy and X-rays but also cosmic rays; in addition, they create and fling into interstellar space many of the heavier elements found in the universe, including those forming Earth's solar system.
(b) Radioactivity
Definitions:
The spontaneous breaking apart, or decay, of unstable nuclei in isotopes. The unstable radioactive isotope is called the parent, and the products of the decay of the parent are called the daughter isotopes.
Or,
Radioactivity is a property exhibited by certain types of matter that emit radiation spontaneously.
Explanations:
The phenomenon was first reported in 1896 by Henri Becquerel for a uranium salt, and it was soon found that all uranium compounds are radioactive due to the uranium's radioactivity. In 1898 Marie Curie and her husband discovered two other naturally occurring, strongly radioactive elements, radium and polonium. The radiation is emitted by unstable atomic nuclei as they attempt to become more stable. The main processes of radioactivity are alpha decay, beta decay, and gamma decay. In 1934 it was discovered that radioactivity could be induced in ordinary matter by artificial transmutation.


(c) Laser
Definition: A laser is a device that emits light (electromagnetic radiation) through a process called stimulated emission.
Explanation: The term "laser" is an acronym for Light Amplification by Stimulated Emission of Radiation. Laser light is usually spatially coherent, which means that the light either is emitted in a narrow, low-divergence beam, or can be converted into one with the help of optical components such as lenses. The coherence of typical laser emission is distinctive. Most other light sources emit incoherent light, which has a phase that varies randomly with time and position.
Characteristics of Lasers:
The physical size of a laser depends on the materials used for light emission, on its power output, and on whether the light is emitted in pulses or as a steady beam. Lasers have been developed that are not much larger than a common flashlight. Various materials have been used as the active media in lasers. The first laser, built in 1960, used a ruby rod with polished ends; the chromium atoms embedded in the ruby's aluminum oxide crystal lattice were pumped to an excited state by a flash tube that, wrapped around the rod, saturated the rod with light of a frequency higher than that of the laser frequency (this method is called optical pumping). This first ruby laser produced intense pulses of red light. In many other optically pumped lasers, the basic element is a transparent, non-conducting crystal such as yttrium aluminum garnet (YAG). Another type of crystal laser uses a semiconductor diode as the element; pumping is done by passing a current through the crystal.
In some lasers, a gas or liquid is used as the emitting medium. In one kind of gas laser the inverted population is achieved through collisional pumping, the gas molecules gaining energy from collisions with other molecules or with electrons released through current discharge. Some gas lasers make use of molecular dissociation to create the inverted population. In a free-electron laser a beam of electrons is “wiggled” by a magnetic field; the oscillatory behavior of the electrons induces them to emit laser radiation. Another device under development is the X-ray laser, which presents special difficulties; most materials, for instance, are poor reflectors of X rays.
Applications of Lasers:
Lasers have been used in industry for cutting and boring metals and other materials, and for inspecting optical equipment. In medicine, they have been used in surgical operations. Lasers have been used in several kinds of scientific research. The field of holography is based on the fact that actual wave-front patterns, captured in a photographic image of an object illuminated with laser light, can be reconstructed to produce a three-dimensional image of the object. One important result of laser research is the development of lasers that can be tuned to emit light over a range of frequencies, instead of producing light of only a single frequency. Work is being done to develop lasers for communication; in a manner similar to radio transmission, the transmitted light beam is modulated with a signal and is received and demodulated some distance away. Lasers have also been used in plasma physics and chemistry.
Uses
When lasers were invented in 1960, they were called "a solution looking for a problem".[23] Since then, they have become ubiquitous, finding utility in thousands of highly varied applications in every section of modern society, including consumer electronics, information technology, science, medicine, industry, law enforcement, entertainment, and the military.
The first application of lasers visible in the daily lives of the general population was the supermarket barcode scanner, introduced in 1974. The laserdisc player, introduced in 1978, was the first successful consumer product to include a laser, but the compact disc player was the first laser-equipped device to become truly common in consumers' homes, beginning in 1982, followed shortly by laser printers.
Some of the other applications include:
• Medicine: Bloodless surgery, laser healing, surgical treatment, kidney stone treatment, eye treatment, dentistry
• Industry: Cutting, welding, material heat treatment, marking parts
• Defense: Marking targets, guiding munitions, missile defence, electro-optical countermeasures (EOCM), alternative to radar
• Research: Spectroscopy, laser ablation, Laser annealing, laser scattering, laser interferometry, LIDAR, Laser capture microdissection
• Product development/commercial: laser printers, CDs, barcode scanners, thermometers, laser pointers, holograms, bubblegrams.
• Laser lighting displays: Laser light shows
• Laser skin procedures such as acne treatment, cellulite reduction, and hair removal.
Q.4. (d) Semiconductors
Definition: A semiconductor is a solid material that has electrical conductivity in between a conductor and an insulator; it can vary over that wide range either permanently or dynamically.
Working: When electricity or light is applied to semiconductors, they change their state between conductive and non-conductive or reflective and non-reflective. The most significant semiconductor is the transistor, which in digital circuits works like an on/off switch. For analog applications, it may be an on/off switch as well, but is more likely used as an amplifier, taking in a low-voltage signal and outputting a higher voltage.
Doping: The property of semiconductors that makes them most useful for constructing electronic devices is that their conductivity may easily be modified by introducing impurities into their crystal lattice. The process of adding controlled impurities to a semiconductor is known as doping. The amount of impurity, or dopant, added to an intrinsic (pure) semiconductor varies its level of conductivity. Doped semiconductors are often referred to as extrinsic. An intrinsic semiconductor has equal concentrations of electrons and holes.
Uses: Semiconductors are important in electronic technology. Semiconductor devices, electronic components made of semiconductor materials, are essential in modern consumer electronics, including computers, mobile phones, and digital audio players. Silicon is used to create most semiconductors commercially, but dozens of other materials are used.
Extra: A semiconductor (a.k.a. a chip) is a material such as silicon, which conducts electrical charges but not as well as metals such as copper and aluminum.
To recap: Chip = semiconductor = integrated circuit. Semiconductors are used in computers, DVD players, cell phones, household appliances, and video games, along with many other products.

Figure:
When electricity or light is applied to semiconductors, they change their state between conductive and non-conductive or reflective and non-reflective. The most significant semiconductor is the transistor, which in digital circuits works like an on/off switch. For analog applications, it may be an on/off switch as well, but is more likely used as an amplifier, taking in a low-voltage signal and outputting a higher voltage. See n-type silicon, doping and chip.


Conceptual View of a Transistor
In a certain type of transistor, the semiconductor material normally acts as an insulator. When it is pulsed with electricity, it becomes electrically conductive for that moment and acts like an electrical bridge.





Q.4. (e) Geothermal Energy
Definition: Energy obtained by tapping the earth’s underground reservoirs of heat, usually near volcanoes or other hot spots on the surface of the Earth.
Applications: Most geothermal resources are in regions of active volcanism. Hot springs, geysers, pools of boiling mud, and fumaroles are the most easily exploited sources. The ancient Romans used hot springs to heat baths and homes, and similar uses are still found in Iceland, Turkey, and Japan. Geothermal energy's greatest potential lies in the generation of electricity. It was first used to produce electric power in Italy in 1904. Today geothermal power plants are in operation in New Zealand, Japan, Iceland, Mexico, the U.S., and elsewhere.
Electricity generation: Three different types of power plants - dry steam, flash, and binary - are used to generate electricity from geothermal energy, depending on temperature, depth, and quality of the water and steam in the area.[4] In all cases the condensed steam and remaining geothermal fluid is injected back into the ground to pick up more heat. In some locations, the natural supply of water producing steam from the hot underground magma deposits has been exhausted and processed waste water is injected to replenish the supply. Most geothermal fields have more fluid recharge than heat, so re-injection can cool the resource, unless it is carefully managed.
Advantages: Geothermal energy offers a number of advantages over traditional fossil fuel based sources.
 From an environmental standpoint, the energy harnessed is clean and safe for the surrounding environment.
 It is also sustainable because the hot water used in the geothermal process can be re-injected into the ground to produce more steam.
 In addition, geothermal power plants are unaffected by changing weather conditions.
 Geothermal power works continually, day and night, providing baseload power.
 From an economic view, geothermal energy is extremely price competitive in some areas and reduces reliance on fossil fuels and their inherent price unpredictability.
 Given enough excess capacity, geothermal energy can also be sold to outside sources such as neighboring countries or private businesses that require energy.
 It also offers a degree of scalability: a large geothermal plant can power entire cities while smaller power plants can supply more remote sites such as rural villages.
Disadvantages: There are several environmental concerns behind geothermal energy.
 Construction of the power plants can adversely affect land stability in the surrounding region. This is mainly a concern with hot dry rock geothermal energy Enhanced Geothermal water into hot dry rock where no water was before.
 Dry steam and flash steam power plants also emit low levels of carbon dioxide, nitric oxide, and sulfur, although at roughly 5% of the levels emitted by fossil fuel power plants.
 Although geothermal sites are capable of providing heat for many decades, eventually specific locations may cool down.

Q.4. (f) Computer Virus
Definition: Computer program designed to copy itself into other programs, with the intention of causing mischief or damage.
Explanation: A virus will usually execute when it is loaded into a computer's memory. On execution, it instructs its host program to copy the viral code into any number of other programs and files stored in the computer. The corrupted programs may continue to perform their intended functions while also executing the virus's instructions, thus further propagating it. The infection may transfer itself to other computers through storage devices, computer networks, and on-line systems. A harmless virus may simply cause a cryptic message to appear when the computer is turned on; a more damaging virus can destroy valuable data. Antivirus software may be used to detect and remove viruses from a computer, but the software must be updated frequently for protection against new viruses.
Worms & Trojan Horses: Viruses are sometimes confused with computer worms and Trojan horses. A worm can spread itself to other computers without needing to be transferred as part of a host, and a Trojan horse is a file that appears harmless. Worms and Trojans may cause harm to either a computer system's hosted data, functional performance, or networking throughput, when executed. In general, a worm does not actually harm either the system's hardware or software, while at least in theory, a Trojan's payload may be capable of almost any type of harm if executed. Some can't be seen when the program is not running, but as soon as the infected code is run, the Trojan horse kicks in. That is why it is so hard for people to find viruses and other malware themselves and why they have to use spyware programs and registry processors.
Most personal computers are now connected to the Internet and to local area networks, facilitating the spread of malicious code. Today's viruses may also take advantage of network services such as the World Wide Web, e-mail, Instant Messaging and file sharing systems to spread, blurring the line between viruses and worms. Furthermore, some sources use an alternative terminology in which a virus is any form of self-replicating malware.

Q.4. (g) Pasteurization
Definition: Partial sterilization of a substance, especially milk or other beverages, by using heat to destroy microorganisms while leaving its chemical makeup unaltered. The process is named for Louis Pasteur, its originator.
Explanation: Pasteurization of milk requires temperatures of about 145 °F (63 °C) for about 30 minutes, or higher temperatures for shorter periods. The treatment destroys any disease-causing organisms (principally Mycobacterium tuberculosis) as well as organisms that cause spoilage. Pasteurization of milk destroys all pathogens, and although it will sour within a day or two, this is not a source of disease. It is achieved either by heating to 63-66 °C for 30 minutes (holder method), followed by immediate cooling, or (the high-temperature short-time process) heating to 71 °C for 15 seconds.














Q.7. (a) Energy
Definition: Capacity for doing work.
Forms of Energy: Energy exists in various forms — including kinetic, potential, thermal, chemical, electrical, and nuclear — and can be converted from one form to another.
Energy Converters: For example, fuel-burning heat engines convert chemical energy to thermal energy; batteries convert chemical energy to electrical energy.
Characteristics of Energy: Though energy may be converted from one form to another, it may not be created or destroyed; that is, total energy in a closed system remains constant. All forms of energy are associated with motion. A rolling ball has kinetic energy, for instance, whereas a ball lifted above the ground has potential energy, as it has the potential to move if released. Heat and work involve the transfer of energy; heat transferred may become thermal energy. See also activation energy, binding energy, ionization energy, mechanical energy, solar energy, zero-point energy.
Renewable Sources of Energy: The main five renewable sources of energy include:
1. Solar energy.
2. Wind energy.
3. Tidal or wave energy.
4. Hydroelectricity.
5. Biomass
How can our country come out of the present energy crisis? …

Q.7. (b) Ceramics
Definition: Ceramics are objects created from such naturally occurring raw materials as clay minerals and quartz sand, by shaping the material and then hardening it by firing at high temperatures to make the object stronger, harder, and less permeable to fluids. The principal ceramic products are containers, tableware, bricks, and tiles.
Types of Ceramic Materials: Ceramic materials can be subdivided into traditional and advanced ceramics.
(1) Traditional ceramics include clay-base materials such as brick, tile, sanitary ware, dinnerware, clay pipe, and electrical porcelain. Common-usage glass, cement, abrasives, and refractories are also important classes of traditional ceramics.
(2) Advanced materials technology is often cited as an enabling technology, enabling engineers to design and build advanced systems for applications in fields such as aerospace, automotive, and electronics. Advanced ceramics are tailored to have premium properties through application of advanced materials science and technology to control composition and internal structure. Examples of advanced ceramic materials are silicon nitride, silicon carbide, toughened zirconia, zirconia-toughened alumina, aluminum nitride, lead magnesium niobate, lead lanthanum zirconate titanate, silicon-carbide-whisker-reinforced alumina, carbon-fiber-reinforced glass ceramic, silicon-carbide-fiber-reinforced silicon carbide, and high-temperature superconductors. Advanced ceramics can be viewed as a class of the broader field of advanced materials, which can be divided into ceramics, metals, polymers, composites, and electronic materials.













Q.8. (a) Camera
Definition: A camera is a device that takes photos of images, either as a photograph or moving images known as videos or movies.
History: The term comes from the camera obscura (Latin for "dark chamber"), an early mechanism of projecting images where an entire room functioned as a real-time imaging system; the modern camera evolved from the camera obscura.
Components & Working: A camera generally consists of an enclosed hollow with an opening (aperture) at one end for light to enter, and a recording or viewing surface for capturing the light at the other end. A majority of cameras have a lens positioned in front of the camera's opening to gather the incoming light and focus all or part of the image on the recording surface. The diameter of the aperture is often controlled by a diaphragm mechanism, but some cameras have a fixed-size aperture. Cameras may work with the light of the visible spectrum or with other portions of the electromagnetic spectrum.
Camera’s Focus: Due to the optical properties of photographic lenses, only objects within a limited range of distances from the camera will be reproduced clearly. The process of adjusting this range is known as changing the camera's focus.
A Camera’s Resemblance in its Function with the Human Eye:












Q.8. (b) Plastics
Definition: Plastics are organic substances made up of huge molecules called polymers.
Constituents: Chemicals found in plastics include carbon, hydrogen, oxygen, and nitrogen. Chlorine, fluorine, sulfur, or silicon may also be present. To make the polymers more flexible or tougher, a plasticizer is added.
Types of plastics:
(1) Thermoplastics: Thermoplastics are formed from long linear chains of molecules (polymers). These polymers can be softened and when cooled regain a solid state. These plastics can be first formed as sheets, pellets, films, tubes, rods, or fibers. These forms can then be reheated and molded into other shapes. For example, nylon thread can be made into fabric. The various chemical and molecular properties of thermoplastics determine whether they are called nylon, polyester, polypropylene, polystyrene, polyethylene, polyvinyl chloride (PVC), or other names.
(2) Thermo-set plastics: Thermo-set plastics are different. These polymers are formed from two directions and produce three-dimensional networks of molecules, not linear chains. Such substances cannot be re-melted. They are formed through compression molding or casting. Thermo-set plastics include phenolic laminates (the original Bakelite), urethane, melamine, epoxy, acrylic, silicone, fluorocarbons, and others.
Uses of Plastics
Plastics are prolific and have many advantages over other heavier, easily corroded, breakable, or more expensive materials.
(1) Uses of thermoplastics:
The five most prevalent plastics are all thermoplastics and account for 90 percent of the plastics of the early twenty-first century. These include
polyethylene, used in all types of bags, diaper liners, agricultural covers, and milk and juice jugs;
polyethylene terephthalate (PET), used principally for soda bottles and videotapes;
polystyrene, used as clear packaging, as a foam (Styrofoam), or for furniture, toys, utensils, and dishes;
polypropylene, used for battery cases, crates, film, molded car parts, appliances, fish nets, and wire coating; and
polyvinyl chloride, used as a flexible substance in film, hoses, rainwear, and wall coverings, or as a rigid substance in pipes, buildings, and credit cards.
(2) Uses of Thermoset Plastics:
The most prevalent thermoset plastics are phenolics, used with formaldehyde and fillers in plywood, fiberglass, and circuit boards; and urea resins, used in polyurethane foam fillers.










Plz add figures yourself.

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Regards

(i) Of what lead pencils are made of?
Ans: Lead pencils are made of graphite. Before the discovery of graphite, soft metals like lead were used for writing. An old name of graphite was 'black lead' and henced the name lead pencils.


(ii) Why is one’s breath visible in cold but not in hot weather?
In cold weather, vapours in exhaled breath take the form of tiny droplets due to cold and thus they become visible.

(iii) What is the chemical composition of diamond?
Ans: Diamond is composed solely of carbon with traces of impurities like boron and nitrogen.

(iv) Name the vaccine that protects against tuberculosis.
Ans: BCG Vaccine. BCG stands for Bacillus Calmette Guerin

(v) Name the disease of the liver that causes a patient to turn yellow.
Ans: Jaundice

Find in the attached file MCQs and Fill in the Blanks that appeared in EDS papers from 1981 to 1990. Only those years are mentioned in which MCQ or Fill in the blank questions have appeared.

Attached Files

MCQs.zip (186.6 KB, 1558 views)

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The precondition for existence of a higher humanity is not the state, but the nation possessing the necessary ability.

Question 1. Select the best option and fill in the appropriate Box on the answer sheet: (50 Marks)


1. Water is heated in a kettle. The inside water is heated by convection. A person sitting near the fire receives heat by :

a) Conduction
b) Convection
c) Radiation
d) Reflection
e) None of these

2. A time can come when we will be able to design a machine which can go on working for ever without the expenditure of energy. Is it possible ?

a) No
b) Yes
c) In due course time
d) Very soon
e) None of these

3. The measurement of rainfall is made by an instrument known as :

a) Hydrometer
b) Barometer
c) Hygrometer
d) Pedometer
e) None of these

4. Light year is a unit of :

a) Distance
b) Time Period
c) Light intensity
d) Time
e) none of these

5. Three elements needed for the healthy growth of plants are :

a) N,P,K
b) N,C,P
c) N,K,C
d) N,S,P
e) none of these

6.Copper can be converted into gold by :

a) Heating
b) Artificial Radioactivity
c) Electroplating
d) Chemical reaction
e) None of these

7. In winter an iron pipe feel colder than a wooden window . This is because wood is :

a) Conductor
b) non-Conductor
c) Semi- Conductor
d) Not a solid while iron is a solid
e) None of these

8. The echo (reflected sound) will be distinctly heard only at ordinary temperatures if the distance of the reflecting surfaces from the source of sound is at least :

a) 1120 ft
b) 120 ft
c) 56fft
d) 100 ft
e) None of these

9. It is possible to recognize a person in the dark by simply hearing his unique voice . It is because of the:

a) pitch
b) Frequency
c) Time period
d) Quality
e) None of these

10. When a ray of sunlight enters a dark room , its straight path become visible because of dust particles hanging in the air. It is because light is :

a) Visible
B) Transparent
c) Invisible
d) opaque
e) None of these

11. A six feet tall lady wants to see her full image in a plane mirror . The minimum length of the mirror will be :

a) 6 feet
b) 12 feet
c) 4 feet
d) 3 feet
e) None of these

12. The principle used in radar is the same as that of Sonar. In radar we use radio waves ; whereas in sonar we use :

A) red waves
b) Infrared waves
c) Ultrasonic
d) super sonic
e) None of these

13. In a fission nuclear reaction , a heavy nucleus breaks up into smaller nuclei whereas in another nuclear reaction two or more than two possibly nuclei are fused to form a heavy nucleus This nuclear reaction is called :

a) Chemical Reaction
b) Nuclear reaction
c) Fission nuclear reaction
d) Fusion nuclear reaction
e) None of these

14. Parsec is a unit of :

a) Energy
b) Time
c) Power
d) Distance
e) None of these

15. German Silver is an alloy of:

A) Zn + Ni
b) Cu + Zn
c) Cu + Ni
d) Cu + Sn
e) None of these

16. The Continent Antarctica lies at the:

a) North pole
b) South pole
c) middle of the earth
d) Equator
e) None of these

17. The temperature of the dead body is:

a) 0 'C
b) 37 '
c) room temperature
d) temperature of the place where it is kept
e) None of these

18. Lactometer is a type of Hydrometer which is used to measure the specific gravity of :

a) Honey
b) Water
c) Milk
d) olive oil
e) None of these

19. Cusec is a unit of :

a) Area
b) Time
c) Distance
d) mass
e) None of these

20. The deepest place on earth is :

a) Trench
b) Mariana Trench
C) Mangrove
d) Groove
e) None of these

21. Twinkling of stars is caused by :

a) Reflection of light
b) Polarization of light
c) refraction of light
d) Interference of light
e) None of these

22. Magnifying power of a simple microscope can be increased by :

a) increasing focal length of the lens
b) Decreasing focal length of the lens
c) Lens of large aperture
d) lens of short aperture
e) None of these

23. Bronze medal is made up of metal :

a) Copper , Zinc
b) Copper , Nickle
c) Copper , Tin
d) Sopper , Silver

24. One of the countries through which equator passes is :

a) Kenya
B) Pakistan
c) Malaysia
d) Malta
e) None of these

25. A very important practical application of properties of matter is hoeing or "godi" practiced by the farmers. This property of matter is called :

a) Elasticity
b) Stress
c) Capillarity
d) Strain
e) None of these

26. It is observed that the total pressure exerted by air on the man of average siz is around 14.7 lb wt. per square inch. But the man feels quite comfortable,. It is because of :

a) An equal and opposite pressure acts from inside
b) of the height of a man
c) of gravity
d) Earth pulls the man upward
e) None of these

27) A nuclear reactor is a device used to carry out controlled nuclear reaction whereas GM counter is a device used to detect :

a) Current
b) Voltage
c) nuclear Radiation
d) power
e) None of these

28. A body can escape the gravitational pull of the earth if it is thrown up with a velocity of:

a) 25 miles per sec
b ) 60 miles per sec
c) 7 miles per sec
d) 10 miles per sec
e) None of these

29. Night vision is possible with the help of :

a) Red light
b) Violet light
c) Infrared Rays
d) Ultra violet Light
e) None of these

30. Myopia is a defect of human eye. it can be corrected by using a lens called :

a) Convex lens
b) Concave lens
c) Cylindrical lens
d) Plano convex lens
e) None of these

31. Walnuts can be broken in the hand by squeezing two together but not one. It is because of :

a) Work done
b) Power
c) Energy
d) Volume
e) None of these

32. The instrument which i specially design for recording earth quake wave is called seismograph which measure earth quake waves on a:

a) Diatonic scale
b) Fahrenheit Scale
c) Richter scale
d) Celsius Scale
e) None of these

33. The planet Mercury completes one rotation around the sun is :

a) 88 days
b) 365 days
c) 98 days
d) 60 days
e) None of these

34. Fossils found in the lowest geological strata are generally most :

a) Advance
b) Complex
c) Primitive
d) Specialized
e) None of these

35. Evolution can be described as :

a) A continuing process
b) A catastrophic event in the past
c) Static
d) The attaining of an ideal type
e) None of these

36. What is the only source of new alleles?

a) Crossing over
b) independent assortment
c) Mutation
d) Fertilization
e) None of these

37. Polygenic characteristic are controlled by :

a) Dominant genes
b) Recessive genes
c) Multiple genes
d) Mutated genes
e) None of these

38. Which of the following , lists the four stages of food processing in order?

a) ingestion , digestion , absorption , elimination
b) digestion , ingestion , absorption , elimination
c) ingestion , absorption , elimination , digestion
d) absorption , digestion , ingestion , elimination
e) None of these

39. In humans , most nutrient molecules are absorbed by the :

a) small intestine
b) stomach
c) liver
d) large intestine
e) None of these

40. The energy needed to fuel essential body processes is called :

a) Essential nutrient level
b) Basal metabolism
c) None of these
d) recommended daily allowance
e) Optimum energy intake

41. Which of the following is an organic molecule needed by the body in small amounts?

a) Protein
b) Vitamin C
c) Zinc
d) Monosaccharide
e) None of these

42. Inhaled air passes through which of the following in the last?

a) Bronchiole
b) Larynx
c) Pharynx
d) Trachea
e) None of these

43. Which of the following is a form of sexual reproduction?

a) Hermaphroditism
B) Fission
c) Fragmentation
d) Budding
e) None of these

44. Cobalt is a material which is :

a) Strongly attracted by a magnet
B) Not attracted by a magnet
c) not a magnet
d) Weakly attracted by a magnet
e) None of these

45. Laughing gas has chemical composition of the following two elements which are :

a) Nitrogen + Hydrogen
b) Nitrogen + Carbon
c) Nitrogen + oxygen
d) Oxygen + Carbon
e) None of these

46. Hepatitis A is transmitted to different individuals by :

a) Water
b) Sneezing
c) Spit
d) Foeces
e) None of these

47. The unit that coordinates different devices of the computer system is :

a) ALU
b)Register
c) Control unit
d) Logical instruction
e) None of these

48. The most abundant element present is in the human body is :

a) Nitrogen
b) Oxygen
c) Carbon
d) Hydrogen
e) None of these

49. Cancer can be treated by :

a) Antibiotics and vaccines
b) Radiotherapy and antibodies
c) Chemotherapy and radiotherapy
d) Antibodies and chemotherapy
e) None of these

50. Animals obtain carbon dioxide mainly from :

a) Starch
b) Sucrose
c) Glucose
d) Glycogen
e) None of these

Note:Corrections are appreciated warmly.






Attempt only five questions. All questions carry equal marks. (50 Marks)

Question # 02 : Write shot note on the following by giving their exact life span and contributions to the field of science. ( Accurate fact will be appreciated) (10)

a) Al- Beruni
b) Ibn- al - Haitham

Question # 03: What do you know about hereditary disease ? Comment how they are transferred from parents to offsprings ? (10)

Question # 04: Write briefly any five of the following: (Answer in three or four sentences) (10)

a) Plaster of Paris

Compound of Calcium.
When hydrated, the form is rigid.
Blessing for broken bones.
Also used for architecture designing(Model designing), Sculpures and for filling purposes in different areas.

b) Reflex Action

A reflex action, also known as a reflex, is an involuntary and nearly instantaneous movement in response to a stimulus. In most contexts, in particular those involving humans, reflex actions are mediated via the reflex arc; this is not always true in other animals, nor does it apply to casual uses of the term 'reflex'.

c) Pace Maker

A pacemaker or artificial pacemaker, is a medical device which uses electrical impulses, delivered by electrodes contacting the heart muscles, to regulate the beating of the heart. The primary purpose of a pacemaker is to maintain an adequate heart rate, either because the heart's native pacemaker is not fast enough, or there is a block in the heart's electrical conduction system.

d) Swine flue

Swine influenza (also called pig influenza, swine flu, hog flu and pig flu) is an infection by any one of several types of swine influenza virus. Swine influenza virus (SIV) or S-OIV (swine-origin influenza virus) is any strain of the influenza family of viruses that is endemic in pigs. Transmission of the virus from pigs to humans is not common and does not always lead to human influenza, often resulting only in the production of antibodies in the blood.

e) Microwave oven

A microwave oven uses microwaves to heat food. Microwaves are radio waves. In the case of microwave ovens, the commonly used radio wave frequency is roughly 2,500 megahertz (2.5 gigahertz). Radio waves in this frequency range are absorbed by water, fats and sugars. When they are absorbed they are converted directly into atomic motion - heat. Microwaves in this frequency range have another interesting property: they are not absorbed by most plastics, glass or ceramics. Metal reflects microwaves, that’s why metal pans do not work well in a microwave oven.

f) Internet

The Internet is a global system of interconnected computer networks that use the standard Internet Protocol Suite (TCP/IP) to serve billions of users worldwide. It is a network of networks that consists of millions of private, public, academic, business, and government networks of local to global scope that are linked by a broad array of electronic and optical networking technologies. The Internet carries a vast array of information resources and services, most notably the inter-linked hypertext documents of the World Wide Web (WWW) and the infrastructure to support electronic mail.

g) Voltage Stabilizer

A voltage regulator is an electrical regulator designed to automatically maintain a constant voltage level. It may use an electromechanical mechanism, or passive or active electronic components. Depending on the design, it may be used to regulate one or more AC or DC voltages.

Question # 05: A) What is global warming ? Is there any a sunny side to global warming ? If yes , explain. (5)
B) What makes the seasons happen ? (5)

Question # 06: In which region of the world , the following animals are found? Give two main characteristics of each. (10)

a) Blind dolphin

Region: Indus River, Sukkur, Pakistan.

The Indus River Dolphin has a long beak and a stocky body. It has a low triangular hump on its back in place of a 'true' dorsal fin. It is gray-brown in color, sometimes with a pinkish belly. The eyes are extremely small, resembling pinhole openings slightly above the mouth. The Indus River dolphin measures between 1.5 - 2.5 m (5 - 8') in length and weighs 80 - 90 kg (180 - 200 lb). It is found exclusively in freshwater, living not only in the main channels, but also, during the flood season, in seasonal tributaries and the flooded lowlands. These dolphins favor silt-laden, turbid waters, at temperatures between 8 - 33°C (46 - 91°F).

b) Kangaroo

Region: Australia

They are large marsupials. A kangaroo has a strong back bone and four legs. The back two are stronger then the front two. It gives birth to undeveloped young which crawl up to the pouch to continue maturing. Most kangaroos and wallabies are herbivores, which means that they eat only plants. They eat mostly leaves and grass, although some also eat fruit, seeds, and fungi. Some of the smaller species are omnivores, animals that eat both animals and plants. These species eat insects and other invertebrates.

c) Panda

Region: China

The Giant Panda is a bear native to central-western and south western China. It is easily recognized by its large, distinctive black patches around the eyes, over the ears, and across its round body. Though it belongs to the order Carnivora, the Giant Panda's diet is 99% bamboo. Other parts of its diet include honey, eggs, fish, yams, shrub leaves, oranges, and bananas when available. The Giant Panda lives in a few mountain ranges in central China, mainly in Sichuan province, but also in the Shaanxi and Gansu provinces. Due to farming, deforestation, and other development, the Giant Panda has been driven out of the lowland areas where it once lived.

d) Kiwi

Region: New Zealand

Kiwis – flightless birds, grow to about the size of a chicken and weigh between three and nine pounds. They have no tail and tiny two inch wings which for all practical purposes, are useless. Despite its awkward appearance, a kiwi can actually outrun a human and have managed to survive because of their alertness and their sharp, three-toed feet, which enable them to kick and slash an enemy. Little Spotted KiwiThe kiwi’s long slender bill has nostrils at the lower end. Using its excellent sense of smell and flexible bill, the kiwi feeds on worms, insects and grubs, supplemented by leaves, berries and seeds. There are five kinds of kiwi in New Zealand - three closely related... Brown Kiwis, the Little Spotted Kiwi and the Great Spotted Kiwi... are pictured at the bottom of the page.

e) Penguin

Region: Antarctica

Penguins are a group of aquatic, flightless birds living almost exclusively in the southern hemisphere, especially in Antarctica. Highly adapted for life in the water, penguins have counter shaded dark and white plumage, and their wings have become flippers. Most penguins feed on krill, fish, squid, and other forms of sea life caught while swimming underwater. They spend about half of their life on land and half in the oceans.



Question # 07:
A) In which organ these parts are present in animals or human body ? (5)
B) Describe the function of each briefly : (5)

1. Coronary artery
2. Sino- Auricular Node
3. Aortic valve
4. Auricle

Question # 08: Differentiate between the following pairs:

a) Hydrometer and Hygrometer

A hydrometer is an instrument used to measure the specific gravity (or relative density) of liquids; that is, the ratio of the density of the liquid to the density of water.

Hygrometer is instrument used for measuring relative humidity. A simple form of a hygrometer is specifically known as a psychrometer and consists of two thermometers, one of which includes a dry bulb and one of which includes a bulb that is kept wet to measure wet-bulb temperature.

b) Perimeter and Telemeter

A perimeter is a path that surrounds an area. The word comes from the Greek peri (around) and meter (measure). The term may be used either for the path or its length - it can be thought of as the length of the outline of a shape. The perimeter of a circular area is called circumference.

A telemeter is a device used to transmit measurements of a quantity to a remote location. Telemeters are generally the physical devices used in telemetry and consist either of analog or digital transmitters.

c) Isotopes and Isomers

Isotopes are different types of atoms (nuclides) of the same chemical element, each having a different number of neutrons. In a corresponding manner, isotopes differ in mass number (or number of nucleons) but not in atomic number

In chemistry, isomers are compounds with the same molecular formula but different structural formulas.

d) Flying mammal and Bird

Flying Mammals are said to fly, such as flying squirrels, gliding possums and colugos, glide rather than fly, and only for short distances. Bats are considered as only flying mammals. The forelimbs of bats are webbed and developed as wings, making them the only mammals naturally capable of true and sustained flight.

Birds (class Aves) are winged, bipedal, endothermic (warm-blooded), egg-laying, vertebrate animals.

e) Vertebrates and Invertebrates

Vertebrates are members of the subphylum Vertebrata, chordates with backbones or spinal columns. Vertebrata is the largest subphylum of chordates, and contains many familiar groups of large land animals. Vertebrates comprise cyclostomes, bony fish, sharks and rays, amphibians, reptiles, mammals, and birds.

An invertebrate is an animal without a backbone. The group includes 95% of all animal species — all animals except those in the Chordate subphylum Vertebrata (fish, reptiles, amphibians, birds, and mammals).

Question # 09:
A) What are pesticides? Explain how these are dangerous to human beings?

B) What do the following scientific abbreviations stand for?

1) STP: Standard Temperature and Pressure
2) LORAN: Long Range Navigation
3) SONAR: Sound Navigation and Ranging
4) MAF: Million Acre Feet
5) MeV: Million Electron Volt, Mega electron Volt
6) MASER: Microwave Amplification By Stimulated Emission of Radiation
7) AWACS: Airborne Warning and Controlling System
8) CCTV : Closed Circuit Tele Vision

__________________
No matter how fast i run or how far i go it wont escape me, pain, misery, emptiness.

Correction: 39 is Small Intestine. Liver does not absorb something from the food. it stores some types of food and regulates the amount of food in the blood that our body needs.

Correction: 29 is c. Infra-red

__________________
Umar Abbas Babar
I Know I am Bad But When Bad is the Best, Bad is the Only Choice

Number 41 is Vitamin-C not Monosaccharide ..

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Bringing rhymes back to the strings of my life.....

Dear peers following some correction are required in above mentioned solution
pls notify

50-Glycogen
49-Chemotherapy and radiotherapy
48-Nitrogen 80% in body
46-foeces
43-Hermaphroditism
42-Bronchiole
41-Monosaccharide (imad bhai its correct)
40-Optimum energy intake
39-small intestine
38-ingestion , digestion , absorption , elimination
37-Multiple genes
36-independent assortment


these corrections are all related medical which i have consulted books and my brother who is in final year of MBBS.

Regards

__________________
Main ne Allah ko Apny irado ke tootany se pehchana":Hazrat Ali (RA)"

Please find one correction in the above!!!

__________________
Umar Abbas Babar
I Know I am Bad But When Bad is the Best, Bad is the Only Choice

40. The energy needed to fuel essential body processes is called :

a) Essential nutrient level
b) Basal metabolism
c) None of these
d) recommended daily allowance
e) Optimum energy intake(body ko energy muhaya krny ka major source optimum energy intke ha,basal metabolism ka mtlb hota ha todd phod kr dena,is k 2 process hain,,1 anabolism and 2 catabolism , smaller molecules are converted into larger molecule and in catabolism larger molecules are broken down into smaller molecule,and in question there is such thing)

48. The most abundant element present is in the human body is :

a) Nitrogen It is most abundent in earth 78% and
b) Oxygen Most abundent element in body is Oxygen,it is about 65%.sory for previouse
c) Carbon
d) Hydrogen
e) None of these

__________________
Main ne Allah ko Apny irado ke tootany se pehchana":Hazrat Ali (RA)"