SSC CGL Previous Year Questions: General Science - 12 - SSC CGL MCQ

Arson is the crime of intentionally and maliciously setting fire to buildings, wild land areas, vehicles or other property with the intent to cause damage. Distinct from spontaneous combustion and natural wildfires, it is considered to be a man–made disaster which is socially induced.

The thyroid gland is one of the largest endocrine gland in the throat, and consists of two connected lobes. It is found at the front of the neck, below the Adam’s apple. The thyroid gland secretes thyroid hormones, which influence the metabolic rate, protein synthesis, and have a wide range of other effects, including on development.

The cerebrum is the seat of intelligence and provides us with the ability to read, write and speak, make calculations and compose music; remember the past and plan for the future; and create works.

The average adult has a blood volume of roughly 5 liters, which is composed of plasma and several kinds of cells. By volume, the red blood cells constitute about 45% of whole blood, the plasma about 54.3%, and white cells about 0.7%.

The normal range of, conentration of fasting blood sugar is 80 to 120 mg/ml; in the testing of true blood sugar, the normal range of concentration is 70 to 100 mg/ml. so normal glucose levels fall between 70 and 150 mg. Higher levels may indicate diseases such as diabetes mellitus.

Entomology is the scientific study of insects. It is derived from the Greek word 'entomos' which means "that which is cut in pieces or engraved/segmented", hence "insect".

(b) and (c) * Exobiology is the branch of science that deals with the possibility of life in space including other planets.

The ionosphere is a region of Earth's upper atmosphere, from about 60 km (37 mi) to 1,000 km (620 mi) altitude and includes the thermosphere and parts of the mesosphere and exosphere, it is ionized by solar radiation, plays an important part in atmospheric electricity and forms the inner edge of the magnetosphere. It has practical importance because among other functions, it influences radio propagation to distant places on the Earth.

Coral reefs are underwater structures made from calcium carbonate secreted by corals. Coral reefs are colonies of tiny animals found in marine waters that contain few nutrients.

Phytochrome is a photoreceptor, a pigment that plants use to detect light. It is a protein with a bilin chromophore. It detects mainly red and far-red region of the visible spectrum and also regulates germination of seeds.

Quenching is a process in which absorbed light energy is dissipated as heat and does not take part in photochemistry. The phenomenon involves quenching of chlorophyll-a fluroescence, which is induced under steady-state illumination.

AIDS virus destroys the T-cells of the immune system. T cells or T lymphocytes belong to a group of white blood cells known as lymphocytes, and play a central role in cell – mediated immunity

Bragg Spectrometer is an instrument used to analyze crystal structure by using X– rays. In it, a beam of collimated X–rays strikes the crystal, and a detector measures the angles and intensities of the reflected beam.

Alpha particles consist of two protons and two neutrons bound together into a particle identical to a helium nucleus, which is generally produced in the process of alpha decay.

The human body requires more calcium than any other mineral. At least 99% of the calcium is found in the bones and teeth, giving them strength and rigidity.

Heterocercal type of tail is found in Sharks. In this type of tail the vertebral column bends upwards and reaches up to the tip of the more prominent dorsal lobe due to which caudal fin becomes asymmetrical and thus called as heterocercal type.

The sigmoid colon is the part of the large intestine. It forms a loop that averages about 40 cm in length

A good conductor of electricity while carrying current remains electrically neutral because the total number of electrons and protons always remains same in the conductor.

Containment of toxic or hazardous constituents in industrial solid wastes is currently being accomplished using: (i) coating grains of waste material with an inert and non-reactive impervious material (microencapsulation), and (ii) coating blocks of waste material with an inert, non-reactive impervious material (microencapsulation).

UV radiation can be an effective viricide and bactericide. Disinfection using UV radiation is commonly used in wastewater treatment and is finding an increased usage in drinking water treatment.

When cells are exposed to sunlight, radiant energy can damage the DNA. For example, ultraviolet irradiation cause covalent bond formation between adjacent thymines on the same strand of DNA. Ultraviolet light is absorbed by a double bond in thymine and cytosine bases in DNA.

In order to manufacture silicones, alkyl-substituted chlorosilanes are used as starting material. Since dimethylsilane contains – OH group at the end of the chain, polymerization and chain length increases. However, the hydrolysis of alkyl trichlorosilane gives very complex cross linked polymer.

Examples of natural colloids can be found in our body itself : blood consists of colloidal sized red blood corpuscles (RBC) which carry the vital oxygen to all the body tissues.

Nickel silver, also known as German silver, is a copper alloy with nickel and often zinc. The usual formulations is 60% copper, 20% nickel and 20% zinc. Nickel silver is named for its silvery appearance, but it contains no elemental silver unless plated.

Atomic absorption spectroscopy is an analytical chemistry technique used for determining concentration of particular metal element and is widely used in pharmaceutics. It was used for the determination of cobalt in Vitamin B12.

Prof. Ananda Mohan Chakrabarty genetically engineered a new species of Pseudomonas bacteria ("the oil-eating bacteria") in 1971 while working for the Research & Development Center at General Electric Company in Schenectady, New York.

Devarda's alloy is an alloy of aluminium (44% - 46%) copper (49% - 51%) and zinc (4% - 6%). Devarda's alloy is used as reducing agent in analytical chemistry for the determination of nitrates after their reduction to ammonia under alkaline conditions. It owes its name to the Italian chemist Arturo Devarda (1859-1944), who synthezised it at the end of the 19th century to develop a new method to analyze nitrate in Chile saltpeter.

Grit chambers are long narrow tanks that are designed to slow down the flow so that solids such as sand, coffee grounds, and eggshells will settle out of the water. Grit causes excessive wear and tear on pumps and other plant equipment. Its removal is particularly important in cities with combined sewer systems, which carry a good deal of silt, sand, and gravel that wash off streets or land.

Cysteine (abbreviated as Cys or C) is an a-amino acid with the chemical formula HO₂CCH(NH₂)CH₂SH. It is a semi-essential amino acid, which means that it can be biosynthesized in humans. The thiol side chain in cysteine often participates in enzymatic reactions, serving as a nucleophile.

Neon is a chemical element with symbol Ne and atomic number 10. It is in group 18 (noble gases) of the periodic table. Neon is a colorless, odorless, inert monatomic gas under standard conditions, with about two-thirds the density of air.