EVERYDAY SCIENCE PAPER 1995

Note: Attempt TEN questions. All questions carry equal marks. Draw diagrams where necessary. Negative marking would be done for incorrect answers in Question Nos. 1 and 14.

1. Which of the following statements are true and which are false.

a) Cryptograms are non-flowering plants.(f)
Cryptograms :coded message: a text or message that is in code or cipher.


b) Reserve food material is usually stored as glycogen in plants.(f)
Reserve food material is usually stored as starch in plants.

Reserve food material is usually stored as glycogen in liver and muscles of animals.

c) Streptococcus is a gram negative bacteria(f)

Streptococcus, genus of spherical, gram-positive, aerobic bacteria. The streptococci occur in pairs or chains, and some species are pathogenic in humans. Streptococcal infections include strep throat, scarlet fever, erysipelas, puerperal fever, and some pneumonias.

Streptococcus:a bacterium that typically occurs in clusters resembling grapes, normally inhabits the skin and mucous membranes, and may cause disease.


d) Spinach is a good source of vitamin K.(f)
d) Spinach is a good source of vitamin A, B2 (Riboflavin) and Iron.

e) Insulin is a hormone secreted by the spleen.(f)
e) Insulin is a hormone secreted by the pancreas.

f) Femur is a bone of the forearm.(f)
f) Femur is a bone of the leg.

g) The moon has no atmosphere.
g) The moon has nearly no atmosphere.because very minute quantity of gases are found.

h) Excessive burning of fossil fuels cause acid rain.(t)

Acid Rain, form of air pollution in which airborne acids produced by electric utility plants and other sources fall to Earth in distant regions. The corrosive nature of acid rain causes widespread damage to the environment. The problem begins with the production of sulfur dioxide and nitrogen oxides from the burning of fossil fuels, such as coal, natural gas, and oil, and from certain kinds of manufacturing. Sulfur dioxide and nitrogen oxides react with water and other chemicals in the air to form sulfuric acid, nitric acid, and other pollutants. These acid pollutants reach high into the atmosphere, travel with the wind for hundreds of miles, and eventually return to the ground by way of rain, snow, or fog, and as invisible “dry” forms.

i) Twenty-first of June is the longest day of the year in the northern hemisphere(t).summer solstice, here is summer
Twenty-first of June is the shortest day of the year in the southern hemisphere(t).here is winter

Vernal Equinox, one of two times of year when the Sun's position makes day and night of equal length in all parts of the Earth. The vernal equinox usually occurs on March 20 or 21 and marks the beginning of the spring season in the Northern Hemisphere.
and marks the beginning of the autumn season in the southern Hemisphere.

Autumnal Equinox, one of two times of year when the Sun’s position makes day and night of nearly equal length in all parts of the Earth. The autumnal equinox, which usually occurs on September 22 or 23, marks the beginning of the fall season in the Northern Hemisphere.

And marks the beginning of the spring season in the southern Hemisphere.


j) Electricity is a secondary source of energy.(t) not confirm, plz check this

2. Define any FIVE of the following scientific terms.

a) Doping: Doping, adding impurities to semiconductor materials in order to change their electrical characteristics.


b) Immunization:Immunization, also called vaccination or inoculation, a method of stimulating resistance in the human body to specific diseases using microorganisms—bacteria or viruses—that have been modified or killed. These treated microorganisms do not cause the disease, but rather trigger the body's immune system to build a defense mechanism that continuously guards against the disease. If a person immunized against a particular disease later comes into contact with the disease-causing agent, the immune system is immediately able to respond defensively.


c) Pasteurization:Pasteurization, process of heating a liquid, particularly milk, to a temperature between 55° and 70° C (131° and 158° F), to destroy harmful bacteria without materially changing the composition, flavor, or nutritive value of the liquid. The process is named after the French chemist Louis Pasteur, who devised it in 1865 to inhibit fermentation of wine and milk. Milk is pasteurized by heating at a temperature of 63° C (145° F) for 30 minutes, rapidly cooling it, and then storing it at a temperature below 10° C (50° F).

d) Modulation:change sound: to change the tone, pitch, or volume of sound, e.g. of a musical instrument or the human voice


e) Catabolism: constructive metabolism, is the process of synthesis required for the growth of new cells and the maintenance of all tissues. Catabolism, or destructive metabolism, is a continuous process concerned with the production of the energy required for all external and internal physical activity. Catabolism also involves the maintenance of body temperature and the degradation of complex chemical units into simpler substances that can be removed as waste products from the body through the kidneys, intestines, lungs, and skin.

f) Reprocessing of reactor fuel.
The spent fuel still contains almost all the original uranium-238, about one-third of the uranium-235, and some of the plutonium-239 produced in the reactor. In cases where the spent fuel is sent to permanent storage, none of this potential energy content is used. In cases where the fuel is reprocessed, the uranium is recycled through the diffusion plant, and the recovered plutonium-239 may be used in place of some uranium-235 in new fuel elements.


3. What do you understand by the term “deforestation”? Discuss its ill-effects on the mankind.
Deforestation, large-scale removal of forest prior to its replacement by other land uses. Forests are removed for a variety of reasons, including agriculture, timber harvesting, and mining, and to make way for roads, dams, and human settlements
Deforestation poses a severe worldwide environmental problem. Forests take enormous amounts of carbon dioxide from the atmosphere in the process of photosynthesis. The destruction of forests exacerbates the accumulation of carbon dioxide in the atmosphere, which then contributes to global warming. In addition, deforestation causes soil erosion and destabilizes watersheds, resulting in flooding or drought.

Deforestation also reduces biodiversity, particularly significant in tropical forests that are home to a substantial portion of the world’s plant and animal species. Deforestation processes are, in general, more destructive in the tropics. Most forest soils in the tropics are far less fertile than temperate soils, and more vulnerable to erosion. This is due to high rainfall, which leaches nutrients from the soil and speeds erosion.



4. Fill in the blanks.
a) The largest planet of the solar system is Jupiter.

Jupiter (planet), fifth planet from the Sun and the largest planet in the solar system. The fourth brightest object in Earth’s sky, after the Sun, the Moon, and Venus, Jupiter is more than three times brighter than Sirius, the brightest star. Due to its prominence in the sky, the Romans named the planet for their chief god, Jupiter.


b) The outermost layer of the earth is called crust.


Crust, outermost layer of Earth. The crust is solid and relatively thin, and it lies below both landmasses and oceans. The dry land of Earth’s surface is called the continental crust. It is about 15 to 75 km (9 to 47 mi) thick. The oceanic crust is thinner than the continental crust. Its average thickness is 5 to 10 km (3 to 6 mi).

Beneath the crust lies a much thicker layer called the mantle, which surrounds Earth’s central core.


c) Newton is the unit of force.

d) Radium was discovered by Marie Curie.

Wilhelm Roentgen, who had discovered X-rays,


e) The memory of the computer is expressed in Bytes.

f) Quartz is a crystalline form of silicon dioxide.

g) AIDS is caused by HIV.

h) Chemical name of gypsum is calcium sulfate.
it is hydrated calcium sulfate

i) Molten super hot material present inside a volcano is called Magma.

Lava, molten or partially molten rock that erupts at the earth’s surface. When lava comes to the surface, it is red-hot, reaching temperatures as high as 1200° C (2200° F).



j) Richter scale measures the severity of earthquake.

5. What is composition of blood? Describe six main functions of blood.

Blood, vital fluid found in humans and other animals that provides important nourishment to all body organs and tissues and carries away waste materials. Sometimes referred to as “the river of life,” blood is pumped from the heart through a network of blood vessels collectively known as the circulatory system.

Blood carries oxygen from the lungs to all the other tissues in the body and, in turn, carries waste products, predominantly carbon dioxide, back to the lungs where they are released into the air. When oxygen transport fails, a person dies within a few minutes. Food that has been processed by the digestive system into smaller components such as proteins, fats, and carbohydrates is also delivered to the tissues by the blood. These nutrients provide the materials and energy needed by individual cells for metabolism, or the performance of cellular function. Waste products produced during metabolism, such as urea and uric acid, are carried by the blood to the kidneys, where they are transferred from the blood into urine and eliminated from the body. In addition to oxygen and nutrients, blood also transports special chemicals, called hormones, that regulate certain body functions. The movement of these chemicals enables one organ to control the function of another even though the two organs may be located far apart. In this way, the blood acts not just as a means of transportation but also as a communications system.

The blood is more than a pipeline for nutrients and information; it is also responsible for the activities of the immune system, helping fend off infection and fight disease. In addition, blood carries the means for stopping itself from leaking out of the body after an injury. The blood does this by carrying special cells and proteins, known as the coagulation system, that start to form clots within a matter of seconds after injury.

Blood is vital to maintaining a stable body temperature; in humans, body temperature normally fluctuates within a degree of 37.0° C (98.6° F). Heat production and heat loss in various parts of the body are balanced out by heat transfer via the bloodstream. This is accomplished by varying the diameter of blood vessels in the skin. When a person becomes overheated, the vessels dilate and an increased volume of blood flows through the skin. Heat dissipates through the skin, effectively lowering the body temperature. The increased flow of blood in the skin makes the skin appear pink or flushed. When a person is cold, the skin may become pale as the vessels narrow, diverting blood from the skin and reducing heat loss.




6. Write short notes (not more than 150 words) on any two of the following.
a) Semi-conductors:Semiconductor, solid or liquid material, able to conduct electricity at room temperature more readily than an insulator, but less easily than a metal.

Such metals as copper, silver, and aluminum are excellent conductors, but such insulators as diamond and glass are very poor conductors .At low temperatures, pure semiconductors behave like insulators. Under higher temperatures or light or with the addition of impurities, however, the conductivity of semiconductors can be increased dramatically, reaching levels that may approach those of metals.


b) Pesticides: a chemical substance used to kill pests, especially insects

The chemical agents called pesticides include herbicides (for weed control), insecticides, and fungicides.


c) Laser:Laser, a device that produces and amplifies light. The word laser is an acronym for Light Amplification by Stimulated Emission of Radiation. Laser light is very pure in color, can be extremely intense, and can be directed with great accuracy. Lasers are used in many modern technological devices including bar code readers, compact disc (CD) players, and laser printers. Lasers can generate light beyond the range visible to the human eye, from the infrared through the X-ray range. Masers are similar devices that produce and amplify microwaves

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