Explore topic-wise InterviewSolutions in Current Affairs.

A) Marylebone Cricket Club

A) A disturbed state of mind

The correct answer is (B) malpighian tubules

The correct answer is (B) bursa copulatrix

The correct answer is (B) perineural sinus

The correct answer is (D) both (A) and (C)

Legs: Three pairs of walking legs are present on the ventral side. Each leg is formed of five podomeres namely coxa, trochanter, femur, tibia and tarsus.Tarsus is the last segment and it is made up of five movable segments or tarsomeres. The last tarsomere bears a pair of claws and cushion-like arolium helpful in clinging.

Spiracles: They are paired respiratory openings. Spiracles are present on the ventrolateral side of the body, in pleural membrane. Cockroaches have two pairs of thoracic and eight pairs of abdominal spiracles.The spiracles open into a series of air sacs from which arise the tubes called trachea. The spiracles let the air into and out of trachea.

Autonomic nervous system (ANS): It consists of four ganglia and a retrocerebral complex. 

The ganglia are as follows: 

1. Frontal ganglion: It is present above the pharynx and in front of brain. 

2. Hypocerebral ganglion: It is present on the anterior region of oesophagus. 

3. Ingluvial ganglion: It is present on crop. It is also called as visceral ganglion. 

4. Ventricular ganglion: It is present on gizzard.

• When bleaching powder comes in contact with air, it reacts with carbon dioxide to form calcium carbonate and releases chlorine gas.

CaOCl₂ + CO₂ → CaCO₃ + Cl₂ ↑ (from air)

• This generated chlorine is known as “available chlorine.”
• On the basis of the percentage of “available chlorine” various brands of bleaching powder are available in the market.

Peripheral nervous system (PNS): 

1. The peripheral nervous system comprises of nerves that arise from various ganglia of CNS. 

2. Six pairs of nerves arise from the supraoesophageal ganglia.They supply to the eyes, antenna and labrum.

3. Nerves arising from the suboesophageal ganglion supply to the mandibles, maxillae and labium. 

4. Nerves arising from the thoracic ganglia supply to the wings, legs and internal thoracic organs. 

5. Nerves from abdominal ganglia go to the abdominal organs of respective abdominal segments.

1. Cockroach has a body cavity or true coelom present around the viscera. 

2. The body cavity of cockroach is known as haemocoel as it is filled with haemolymph (blood). Cockroaches have open type of circulation thus; the body cavity is filled with haemolymph. 

3. The body cavity contains fat bodies. These are in the form of loose, whitish mass of tissue. They are made up of large, polygonal cells which contain fat globules, proteins and sometimes glycogen.

Compound eyes: Compound eyes are paired, dark, kidney — shaped structures placed on the dorsolateral sides of the head. They are made up of large number of hexagonal ommatidia i.e. around 2000 ommatidia (sing, ommatidium). These ommatidia are the structural and functional unit of compound eye, each forming an image of very small part of visual field. Collectively, the compound eye produces a mosaic image. Even though the compound eye gives a mosaic or hazy vision yet the animal can detect the slightest movement of the object. Compound eyes provide low resolution and more sensitive vision.

• Anodizing is process of forming a protective rayer of hydrated aluminium oxide on utensils.
• Due to anodizing, the surface of the cooking utensils become non-standing, non-toxic and non-reactive with the ingredients of the foot. 
• These utensils get heated faster and withstand high heat.
• Also the amount of butter, ghee or oil used to cook food in these type of utensils is neglible.
• These utensils are tough, durable and resistant to corrosion. Hence, we use anodized cooking utensils like gridders and cookers.

Each gland has a salivary duct. Both the ducts unite to form a common salivary duct.

Exoskeleton: Tough, waxy, non-living chitinous exoskeleton protects the body of the cockroach. It is made up of nitrogenous polysaccharide – chitin that provides strength, elasticity and surface area for attachment of muscles. Each body segment of cockroach is covered by four chitinous plates called sclerites namely, dorsal tergum, ventral sternum and two lateral pleurons.

• When soap is mixed with hard water, calcium and magnesium salts of fatty acids are formed. 
• These being water insoluble, they form a precipitate and that is why lather is not formed.

• A protective layer is formed naturally on the surface of aluminium metal by reaction with oxygen in air. 
• In the anodizing process, this layer is made of the desired thickness. Anodizing is done by electrolysis. 
• Dilute Sulphuric acid is taken in the electrolytic cell and the aluminium article is dipped in it as the anode. 
• When an electric current is passed, hydrogen gas is released at the cathode and oxygen gas at the anode. 
• A reaction with oxygen occurs and a layer of hydrated aluminium oxide is formed on the anode. Therefore, aluminium article is used as an anode in the anodizing process.

• We regularly use artificial colours on Rang Panchami. 
• The red colour used on Rang Panchami is very dangerous. It contains a high proportion of mercury in it. 
• This poses risks like blindness, skin cancer, asthma, itching of the skin, permanent blocking of sweat pores, etc. 
• Therefore, it is necessary to use eco-friendly colours. 
• We will prepare colours for Rang Panchami from natural resources such as beet root, flowers of flame of forest, spinach, flame tree (gulmohar) and protect your health by using these.

Antennae: They are also called as feelers.These are long, filamentous, segmented structures that can move in all directions.They are lodged in membranous pits known as antennal sockets.They are tactile (touch) as well as olfactory (smell) organs. 

Function: They are useful in locating the food material in the vicinity.

• To prevent the occurrence of these problem, instead of using artificial colours, natural colours should be used. 
• Natural colours are prepared from natural resources such as beet root, flowers of flame of forest, spinach, flame tree (gulmohar).

• After playing colours on Rang Panchami we may get problems such as risks of blindness, skin cancer, asthma, itching of the skin, permanent blocking of sweat pores etc. 
• This is because the colours used in rang panchami specially the red colour is very dangerous.
• It contains a high proportion of mercury in it.

• On painting the house and furniture with artificial colours which are dangerous, we may get problems such as risks of blindness, skin cancer, asthma, itching of the skin, permanent blocking of sweat pores, etc.
• This is because the colours contain a high proportion of mercury in it.

• Long before pure chemicals were manufactured in labs, people used plants for medicine. 
• There are over a hundred active ingredients derived from plants for use as drugs and medicines. 
• The emergence of synthetic chemistry in the 1800s opened up new avenues for scientific research into drugs. 
• Many chemists tried to locate medically active ingredients in plants (for instance the important malaria remedy quinine), and subsequently tried to make those substances in the laboratory in order to become independent of plant supplies.
•  At the same time, a new industry developed as scientists developed processes to synthesise new chemicals on a large scale.
• New production methods developed in the late 1800s and early 1900s made it easier to standardise, package and transport medicines.

The use of methods like Teflon coating became more common because of following properties of teflon:

• The atmosphere, rain water and chemical substances have no effect on Teflon. 
• Neither water nor oil will stick to Teflon coated articles. 
• High temperatures do not affect Teflon as its melting point is 327 °C. 
• Teflon coated articles are easy to clean. 
• Teflon is a poor conductor of electricity.

• Powder coating is a method of applying a layer harder than paint on the surface of an iron object to prevent rusting.
• In this method, a polymer resin, a pigment and some other ingredients are melt, mixed, cooled and ground into a uniform powder. 
• This powder is sprayed on the polished metal surface by electrostatic spray deposition (ESD).
• In this method, the particles of the powder are given an electrostatic charge due to which a uniform layer of the powder sticks to the metal surface. 
• Then the object is heated in the oven along with the coating. 
• A chemical reaction occurs in the layer, resulting in the formation of long cross-linked polymeric chains.

(1) Low-grade fats and oils 

(2) Polycythemia

(3) Tumour detection 

(4) 15% 

(5) NaHCO.

1. This picture shows powder coating of the given object. Powder coating is a method of applying a layer harder than paint on the surface of an iron object to prevent rusting.

2. In this method, a polymer resin, a pigment and some other ingredients are melt mixed, cooled and ground into a uniform powder.

3. This powder is sprayed on the polished metal surface by electrostatic spray deposition (ESD).

4. In this method, the particles of the powder are given an electrostatic charge due to which a uniform layer of the powder sticks to the metal surface.

5. Then the object is heated in the oven along with the coating.

6. A chemical reaction occurs in the layer, resulting in the formation of long cross-linked polymeric chains.

7. This powder coating is highly durable, hard and attractive. Powder coating can be done on plastic and medium density fibre (MDF) board in day to day use as well.

Answer is (B) Kanauj

• Powder coating is a method of applying a layer harder than paint on the surface of an iron object to prevent rusting.
• In this method, a polymer resin, a pigment and some other ingredients are melt, mixed, cooled and ground into a uniform powder.
• This powder is sprayed on the polished metal surface by electrostatic spray deposition (ESD).
• In this method, the particles of the powder are given an electrostatic charge due to which a uniform layer of the powder sticks to the metal surface.
• Then the object is heated in the oven along with the coating.
• A chemical reaction occurs in the layer, resulting in the formation of long cross-linked polymeric chains.
• This powder coating is highly durable, hard and attractive.
• Powder coating can be done on plastic and medium density fibre (MDF) board in day to day use as well.

• In the pH scale, the pH of solutions varies from 0 to 14 in accordance with the strength of the acids or base. 
• The pH scale shows different colours at different values of pH. Colour from dark red to yellow or from pH value 0 to 6 indicates the substances are acidic. 
• Colour from light blue to violet or from pH value 8 to 14 indicates the substances are basic. 
• Green colour or pH value 7 indicates the substances are neutral.

• Advanced ceramics requires a temperature of 1600 to 1800 °C and an oxygen-free atmosphere for firing. 
• This process is called sintering.

• Detergent is a water-soluble cleansing agent which combines with impurities and dirt to make them more soluble, and differs from soap in not forming a scum with the salts in hard water.
• Today, detergents are more likely to be a mixture of synthetic chemicals and additives cooked up in a huge chemical plant and, unlike traditional soap, they’re generally liquids rather than solids.
• Detergents are used in everything from hair shampoo and clothes, washing powder to shaving foam and stain removers.
• The most important ingredients in detergents are chemicals called surfactants – a word made from bits of the words surface-active agents.

(1) Acidic 

(2) Potassium phosphate 

(3) Sodium hydrogen carbonate 

(4) 24H₂O 

(5) MgSO₄.7H₂O

• When radioactive radiations are allowed to pass through two oppositely charged plates they get separated. This method was introduced by Rutherford in 1902.
• Rutherford and Willard studied the radiation emitted by radioactive substances.
• For this purpose, the rays were allowed to pass through an electrical field and a photographic plate was held in their path.
• It was found that the radiation was divided into three types.
• One type of radiation deviated slightly towards the negatively charged plate, while the second type of radiation deviated substantially towards the positively charged plate.
• However, the third type of radiation did not deviate at all in the electrical field.
• The rays which deviated slightly toward negatively charged plate are called alpha rays.
• Those which deviate substantially towards the positively charged plate are called beta rays and those which did not deviate at all are called gamma rays.

Uses of dyes :

• They are used for colouring cloth and hair. 
• Fluorescent colours are used to make street boards that are visible at night.
• Dyes are used to polish leather shoes, purses and chappals.

• On 26th April 1986, the graphite reactor in the Chernobyl atomic power plant exploded, and suddenly the radioactive isotopes and radiation came out. 
• Due to this episode, radioactive isotopes entered the human body through water and land and caused genetic disorders.
• These got carried further into the next generation. 
• Thyroid disorders increased in children as well as adults. 
• As a result, the incidence of throat diseases is greater there than in other places.

(D) Chauhans

• It is a misconception that radioactive elements are used only for making an atom bomb. 
• Radioactive isotopes are used in various fields such as scientific research, agriculture, industry, medicine, etc. 
• Radioactive substances are used in two ways. 
• By using the radiation alone. 
• By using the radioactive element itself.

Field of agriculture:

• The genes and chromosomes that give seeds properties like fast growth, higher productivity, etc. can be modified by means of radiation. 
• The radioactive isotope cobalt-60 is used for food preservation. 
• Onions, potatoes are irradiated with gamma rays from cobalt-60 to prevent their sprouting. 
• Strontium-90 is used as a tracer in the research on various crops.

• Blue vitriol is used in the blood test for diagnosing anaemia. 
• Bordeaux mixture which is a mixture of slaked lime and blue vitriol is used as a fungicide on fruits like grapes and musk melon.

Luminescent paint and radioluminescence:

• The radioactive substances radium, promethium, tritium with some phosphour are used to make certain objects visible in the dark, for example, the hands of a clock, and certain other objects. 
• Krypton-85 is used in HID (High Intensity Discharge) lamps while promethium-147 is used in portable X-ray units as the source of beta rays.

(A) Al-Biruni

Properties and uses of sodium bicarbonate:

(i) NaHCO₂ reacts with moist litmus paper and red litmus turns blue which means that it is basic in nature. 

(ii) It is used to make bread, cake, dhokla. 

(iii) Being basic in nature it is used to reduce acidity in the stomach. 

(iv) NaHCO₃ is used to make the active substance CO₂ in the fire extinguisher. 

(v) Baking soda is used to clean an oven.

• Elements with a high atomic number such as uranium, thorium, radium have a property of spontaneously emitting invisible, highly penetrating and high energy radiation. This property is called radioactivity.
• A substance having this property is called a radioactive substance.

Medical science:

• Polycythemia: The red blood cell count increases in the disease polycythemia. Phosphorus- 32 is used in its treatment. 
• Bone cancer: Strontium-89, strontium-90, samarium-153 and radium-223 are used in the treatment of bone cancer.
• Hyperthyroidism: Enlargement of thyroid gland, weight loss in spite of appetite, insomnia are the symptoms of hyperthyroidism.
• It occurs due to overproduction of hormones by the thyroid gland. Iodine-123 is used in the treatment of hyperthyroidism.
• Tumour detection: Boron-10, iodine-131, cobalt-60 are used in the treatment of brain tumour, while arsenic-74 is used in detection of small tumours in the body.

• Food colours are mixed in most soft drinks and foodstuffs available in the market. 
• These food colours are in the form of powders, gels and pastes. 
• Food colours are used in domestic as well as commercial products. 
• Certain colours and essences are added to ice cream, ice candies, sauces, fruit juices, cold drinks, pickles, jams and jellies.
• Food colours are often found to be added to packaged meat (chicken, mutton), chilli powder, turmeric, sweets and other similar substances so as to give them a good colour.
• Food colours are natural as well as artificial. 
• The food colours prepared from seeds, beetroot, flowers and fruit concentrate are natural.
• Tetrazene, sunset yellow are artificial food colours used extensively. 
• However, over-consumption of artificial food colours can be detrimental to health. Therefore, usage of natural food colours is always good.

(B) Mahmud Ghazni

• The central nervous system is affected by radioactive radiations. 
• Hereditary defects are generated by bombardment of radiation on D.N.A in the body.
• Radioactive radiation can penetrate the skin, and causes diseases like skin cancer, leukemia.
• The radiative pollutants created due to explosions enter the body through air and it is difficult to control them.
• The radioactive pollutants released in the sea enter the bodies of fishes and through them enter the human body.
• The radioactive paint on the watch can cause cancer.
• The radioactive isotopes strontium-90 can enter the body through plants, fruits, flowers, cereals, milk, etc. and cause diseases like bone cancer, leukemia.

Correctly matched column: