SSC CGL Previous Year Questions: General Science - 10 - SSC CGL MCQ

Night blindness is the first sign of vitamin A deficiency. Night blindness and its worsened condition, xerophthalmia, are markers of vitamin A deficiency, as it can also lead to impaired immune function, cancer, and birth defects.

Cloves are the aromatic flower buds of a tree in the family Myrtaceae, Syzygium aromaticum. They are native to the Maluku Islands in Indonesia, and are commonly used as a spice.

Heating gypsum partially dehydrates the mineral by driving off approximately 75% of water contained in its chemical structure. The partially dehydrated mineral is called calcium sulfate hemihydrate or calcined gypsum commonly known to be Plaster of Paris.

Neutron was discovered by a British Physicist named Sir James Chadwick. In1932, Chadwick showed that the radiation from the element beryllium, caused by the bombardment of alpha particles is actually a stream of electrically neutral particles. He called these particles neutrons. He also studied some other properties of these particles. Neutrons directly emitted from atomic nuclei are termed as fast neutrons

Carbonated beverages like soda get their name from the carbon dioxide dissolved in the beverage. Most gases will dissolve in water (which is the main component of soda) but carbon dioxide is particularly good at dissolving and it adds a slightly sour taste to the beverage. It may also be added to make it reminiscent of the carbonation found in fermented beverages like champagns.

Biogas is a clean unpolluted and cheap source of energy in rural areas. It consists of 55-70% methane which is inflammable. Biogas is produced from cattle dung in a biogas plant commonly known as gobar gas plant through a process called digestion.

Carbon credit is a permit which allows a country or organization to produce a certain amount of carbon emissions and which can be traded if the full allowance is not used. It is associated with protection of environment.

A green leaf is green because of the presence of a pigment known as chlorophyll, inside chloroplast.

Temperature is measured by a thermometer. One of the most common devices for measuring temperature is the glass thermometer. This consists of a glass tube filled with mercury or some other liquid, which acts as the working fluid. Temperature increase causes the fluid to expand, so the temperature can be determined by measuring the volume of the fluid. Such thermometers are usually calibrated so that one can read the temperature simply by observing the level of the fluid in the thermometer.

At 25° C the pH of pure water is very close to 7. Acids have a pH less than 7 while bases have a pH greater than 7. Because it has a pH of 7, water is considered to be neutral. It is neither an acid nor a base, but is the reference point for acids and bases.

Distillation is a process of separating the component substances (impurities) from a liquid mixture by selective evaporation and condensation. The end result is pure water.

H₂SO₄ is the sulphuric acid which is a highly corrosive strong mineral acid . It cannot be used in food industry as a preservative.

The pancreas is a glandular organ in the upper abdomen, but it serves as two glands a digestive exocrine gland and a hormone-producing endocrine gland. Functioning as an exocrine gland, the pancreas produce enzymes to break down the proteins, lipids, carbohydrates, and nucleic acids in food. Functioning as an endocrine gland, the pancreas secretes the hormones insulin and glucagon to control blood sugar levels throughout the day.

Due to the action of motor cells at the base of the petiole and leaflets, the leaves of touch me not plant closes. The motor cells are activated by touch of the sensitive hairs present on the surface of touch-me-not plant. Like a number of other plant species, it undergoes changes in leaf orientation termed "sleep" or nyctinastic movement. The foliage closes during darkness and reopens in light.

The theoretical basis for plant tissue culture was proposed by botanist Gottlieb Haberlandt in1902 on his experiments on the culture of single cell.

Beak is technically only the external surface of a bird's mouth. The entire mouth structure of a bird is called the bill. The bill (or rostrum) consists of a bony framework, a vascular layer containing the blood vessels and nerves, a layer of connective tissue, which "glues" the beak to the bones, and the beak, which is the outer sheath covering the jaw bones. The beak is composed of keratin - the same tough, insoluble protein found in fingernails, hoofs, antlers and horns.

External ear is present in Mammals. Many mammals can move the pinna (with the auriculares muscles) in order to focus their hearing in a certain direction in much the same way that they can turn their eyes. Most humans, unlike most other mammals, do not have this ability.

Archimedes used the principle of buoyancy to find the purity of gold. According to which a body immersed in fluid experiences a buoyant force equal to the weight of the fluid it displaces. With the help of this principle, the density of the golden crown and solid gold was compared by balancing the crown on a scale with a reference piece, this set up is then immersed in water. If the crown is less dense than gold, it will displace more water, and thereby will experience a greater buoyant force than the reference piece.

The kinetic energy of a non-rotating object of mass m traveling at a speed v is 1/2mv². If m and v are increased
to twice its magnitude, then K.E= 1/2 * 2m * 2v * 2v = 1/2mv² (8) = 8 times kinetic energy.

The gravitational force is inversely proportional to the square of the distance: If you double the distance between the two bodies, the force of gravity is reduced to one-fourth its original value.

Stationary wave can occur because the medium is moving in the opposite direction to the wave, or it can arise in a stationary medium as a result of interference between two waves travelling in opposite directions

Two oxygen atoms can both achieve stable structures by sharing two pairs of electrons joined in a double bond. O=O. Each line represents one pair of shared electrons.

Helium is used by deep sea divers in their diving tanks as a substitute of nitrogen. The trouble with nitrogen in this situation is that nitrogen is a fairly heavy gas, and is soluble in blood at high pressure. Long term use of nitrogen can cause a strange sense of euphoria, or well being called nitrogen narcosis. This is a bit like being drunk, and makes the diver unable to assess dangers. Divers who work at depth or for long periods use a mixture of 20% Oxygen and 80% Helium. Helium is used for a number of reasons - It is light, cheap, and does not dissolve in blood. Being inert it cannot be toxic to the diver or corrosive to equipment.

The atomic number of uranium is 92, and the mass number of the isotope is given as 238. Therefore, it has 92 protons, 92 electrons, and 238 – 92 = 146 neutrons.

Auxanometer measures root pressure which is developed in the xylem of the roots . The auxanometer measures plant growth as well as the pressure developed within the xylem cells of roots.

Cell becomes turgid because of endosmosis. Plant cells need to be turgid (i.e. rigid) to support plant tissues. Plant cells become turgid when the concentration inside the cell is higher than outside. Therefore water moves into the cell by osmosis, and the vacuole swells and pushes against the cell wall. Endosmosis is the movement of water molecules from outside to inside of a cell through osmosis process.

Imbibition is the absorption of one substance by another, through the uptake of water or similar liquide.

A physical phenomenon known as osmosis causes water to flow from an area of low solute, high water concentration to an area of high solute, low water concentration, until the two areas have an equal ratio of solute to water. Normally, the solute diffuses toward equilibrium as well; however, all cells are surrounded by a lipid bilayer cell membrane which permits the flow of water in and out of the cell but restricts the flow of solute under many circumstances. As a result, when a cell is placed in a hypotonic solution, water rushes into the membrane, increasing the cell's volume.

Transboundary pollution is the pollution that originates in one country but is able to cause damage in another country's environment, by crossing borders through pathways like water or air. Acid rain is a classic example of a transboundary pollution because it can be blown anywhere by the wind. Sulphur dioxide and nitrous oxides are the two main chemicals that react with water to make acid rain. The chemicals are commonly released from power stations, factories and transport.

The Nicobar pigeon is a pigeon found on small islands and in coastal regions from the Nicobar Islands, India, through the Malay Archipelago, to the Solomons and Palau. It is the only living member of the genus Caloenas and the closest living relative of the extinct dodo.