Explore topic-wise InterviewSolutions in Current Affairs.

Cancer detection and diagnosis: Early detection of cancers, is essential as it allows the disease to be treated successfully in many cases. Cancer detection is based on biopsy and histopathological studies of the tissue and blood and bone marrow tests for increased cell counts in the case of leukemias. In biopsy, a piece of the suspected tissue cut into thin sections is stained and examined under microscope (histopathological studies) by a pathologist. Techniques like radiography (use of X-rays), CT (computed tomography) and MRI (magnetic resonance imaging) are very useful to detect cancers of the internal organs. Computed tomography uses X-rays to generate a three-dimensional image of the internals of an object. MRI uses strong magnetic fields and non-ionising radiations to accurately detect pathological and physiological changes in the living tissue.

• Antibodies against cancer-specific antigens are also used for detection of certain cancers. Techniques of molecular biology can be applied to detect genes in individuals with inherited susceptibility to certain cancers. Identification of such genes, which predispose an individual to certain cancers, may be very helpful in prevention of cancers. Such individuals may be advised to avoid exposure to particular carcinogens to which they are susceptible (e.g., tobacco smoke in case of lung cancer).

• Treatment of cancer: The common approaches for treatment of cancer are surgery, radiation therapy and immunotherapy. In radiotherapy, tumor cells are irradiated lethally, taking proper care of the normal tissues surrounding the-tumor mass. Several chemotherapeutic drugs are used to kill cancerous cells. Some of these are specific for particular tumors. Majority of drugs have side effects like hair loss; anemia, etc. Most cancers are treated by combination of surgery, radiotherapy and chemotherapy. Tumor cells have been shown to avoid detection and destruction by immune system. Therefore, the patients are given substances called biological response modifiers such as a-interferon which activates their immune system and helps in destroying the tumor.

Correct option is (b) 1770

Godowns: The place where the storage of dry grains to protect them from pests and microorganisms.

Threshing: The dry plant’s stocks are beaten on a hard surface to remove the grain.

Cold storage units: Here the vegetables, fruits, tamarind, chilies, and other products that are usually damaged and decolored within a short time.

Winnowing: In winnowing the grains are poured out of a basket or tray held high up the wind blows the chaff, dust, and lighter seeds aside, while the heavy grains collect below.

Winnowing is a process by which chaff is separated from grain. It can also be used to remove pests from stored grain. Winnowing usually follows threshing in grain preparation.

Weeding: Removal of undesirable plants (weeds) which grow along with crop plants.

Weedicides: When crops are fully grown and may not be suitable for uprooting weeds, farmers use weedicides like 2-4 D’chloro phenoxy acetic acid to control or kill the weeds.

Condensation - Dew is a form of condensation. condensation is the process by which water vapour in the air gets converted in to tiny droplets of water or ice. Dew formsin winters when the temperature is very low but not below 0°C. Moist air comes in contact with the cold surfaces near the ground. The water vapour in the air changes to water and we see it as dew drops on grass or on plants. Dew drops are beneficial for plants. 

Precipitation – Precipitation is the falling of atmospheric moisture as a result of condensation. It has many forms such as rainfall, snowfall, and hail.

When the weather conditions of the previous day are published, it is called a weather report. Weather forecasting is the application of science and technology to predict the state of the atmosphere for a given location. Nowadays it is made with the help of data gathered from weather satellites and radar systems. Forecasts help to plan what to wear, when to travel or which products to stock in super markets. It’s specially important for farmers, builders, sailors or anyone else who works out doors.

Isohytes : A weather map, which shows, by the help of lines, the amount of rainfall a place receives. Each of these lines is made by joining points that show the same amount of rainfall received in a given period. These lines are known as isohyets. 

Isotherm : On the map, places experiencing the same temperature at a given time are connected with a line. This line is known as an isotherm. Each of these points on the line reflects one temperature reading, or an average of several readings, over a period of time.

The instrument used for measuring ralative humidity is called hygrometer. the hygrometes consists of wet and dry bulb thermometer.The dry bulb thermometer is an ordinary thermometer while the wet bulb thermometer is kept wet by a wick that dips in to a container of distilled water. the wet bulb thermometer shows the lower temperature than the actual temperature as evaporation from the moist wick has a cooling effect. A larger difference between readings of two thermometers means low relative humidity and small difference means high relative humidity.

A large difference between the readings of the two thermometers means low relative humidity and a small difference between them means high relative humidity.

Beaufort scale is the scale that is used to estimate wind speed. The scale is based on the effect of the wind at different speeds.

In the early morning dew surrounds the leaves of plant with moisture and plant does not close its stomata.

Relative humidity is the ratio of the actual amount of water vapour present in the air and the total amount the air can hold at a given temperature. lt is expressed in percentage. while absolute humidity is measured in grams per cubic metre.

Following are the three main functions related to information: 

1.  Collecting information 

2.  Storing information 

3.  Distributing information

The protection of sensitive data and personal information from unintentional and intentional attacks and disclosure is called security.

Plagiarism occurs due to lack of knowledge.

Stealing someone else’s ideas or information and presenting them as your own is called plagiarism.

Follow the below given guidelines to avoid plagiarism: 

1. To avoid plagiarism, instead of copying the language of the book as it is, try to put it in your own language/words. 

2. One should have a clear understanding of plagiarism and its consequences, so that no one can perform it unintentionally. 

3. If copying someone else’s work in our task, word for word, then do not forget enclosing it in quotes and also mention its source. 

4. Another way is to credit the author has write which was useful for your task and not taking credit for it yourself.

True 

Lack of planning, time is called a plagiarism.

Web master helps in managing the administration and implementation of a Website.

A hydathode is a type of epidermal pore, commonly found in higher plants. Structurally, hydathodes are modified stomata, usually located at leaf tips or margins, especially at the teeth. Hydathodes occur in the leaves of submerged aquatic plants such as ranunculus fluitans as well as in many herbaceous land plants.

Histogen theory is proposed by Hanstein (1868) and supported by Strassburgur. 

The shoot apex comprises three distinct zones.

1. Dermatogen: It is a outermost layer. It gives rise to epidermis.

2. Periblem: It is a middle layer. It gives rise to cortex. 

3. Plerome: It is innermost layer. It gives rise to stele.

Correct Answer is: (b) Hofmeister

It is the inner zone of shoot apex,that forms cortex and stele of shoot.

Apical cell theory is proposed by Hofmeister (1852) and supported by Nageli (1859). A single apical cell is the structural and functional unit. This apical cell governs the growth and development of whole plant body. It is applicable in Algae, Bryophytes and in some Pteridophytes.

Apical cell theory is proposed by Nageli. The single apical cell or apical initial composes the root meristem. The apical initial is tetrahedral in shape and produces root cap from one side. The remaining three sides produce epidermis, cortex and vascular tissues. It is found in vascular cryptogams.

Correct Answer is: (d) Duchaigne

It is the most common type of collenchyma with irregular arrangement and thickening at the angles where cells meet., eg: Hypodermis of Datum and Nicotiana.

• Lowering of temperature at a given pressure, increases the rate of adsorption of gases on charcoal powder. By using this principle, high vacuum can be attained by adsorption.
• A vessel evacuated by vacuum pump is connected to another vessel containing coconut charcoal cooled by liquid air. The charcoal adsorbs the remaining traces of air or moisture to create a high vacuum.

The allotropes of carbon are classified into two types. 

They are 

i) Amorphous forms, 

ii) Crystalline forms. 

Examples : Amorphous forms :

Coal, coke, wood charcoal, animal charcoal, lamp black, gas carbon, petroleum coke, sugar charcoal, etc. 

Crystalline forms : 

Diamond, graphite, and buckminsterfullerene.

i. Catalysis (Heterogeneous catalysis) :

• The solid catalysts are used in many industrial manufacturing processes.
• For example, iron is used as a catalyst in manufacturing of ammonia, platinum in manufacturing of sulphuric acid, H₂SO₄ (by contact process) while finely divided nickel is employed as a catalyst in hydrogenation of oils.

ii. Gas masks :

• It is a device which consists of activated charcoal or mixture of adsorbents.
• It is used for breathing in coal mines to avoid inhaling of the poisonous gases.

A measure of the elastic force at the surface of a liquid is called surface tension. 

OR 

Surface tension is the amount of energy required to stretch or increase the surface of a liquid by a unit area.

(D) Dispersion forces

• The adsorption phenomenon is caused by dispersion forces (also known as London dispersion forces or van der Waals forces) which are short range and additive. Adsorption force is the sum of all interactions between all the atoms.
• The pulling interactions cause the surface of a liquid to tighten like an elastic film.
• A measure of the elastic force at the surface of a liquid is called surface tension.
• There is a tendency to have minimum surface tension, i.e., decrease of free energy, which leads to adsorption.

Because at those distances the light rays diverge each other.

Consider the following two examples:

• Example 1: When a metal spoon is dipped in milk and taken out, it is observed that a film of milk particles covers the spoon surface.
• Example 2: If a cold water bottle is taken out from the refrigerator and kept on a table for a while, water vapour is seen to condense on the outer surface of the bottle, forming droplets or a film.
• In the above examples, the milk particles or the water molecules from the air get adsorbed on the surface of the spoon and the bottle, respectively.
• Similarly, surfaces of many objects around us are exposed to the atmosphere. Water molecules as well as other gas molecules such as N₂ , O₂ , from the air form an invisible multimolecular film on these objects. This is known as the phenomenon of adsorption.

When the adsorbent such as gas molecules are accumulated at the surface of a solid on account of weak van der Waals forces, the adsorption is termed as physical adsorption or physisorption.

Characteristics:

• The van der Waals forces involved in physical adsorption are similar to forces causing condensation of gas into liquid. Thus, heat is released in physisorption.
• The heat released during physisorption is of the same order of magnitude as heat of condensation.
• Due to weak nature of van der Waals forces, physisorption is weak in nature.
• The adsorbed gas forms several layers of molecules at high pressures.
• The extent of adsorption is large at low temperatures.
• The equilibrium is attained rapidly.
• Physisorption is readily reversed by lowering of pressure of gas or by raising temperature.

Following are some examples of adsorption:

• Adsorption of gases like hydrogen and oxygen by finely divided metals, namely, platinum, palladium, copper, nickel, etc.
• Adsorption of gases like nitrogen and carbon dioxide by activated charcoal.
• Removal of colouring matter like an organic dye, for example, methylene blue. When charcoal is added to methylene blue solution and shaken, it becomes colourless after some time as dye molecules accumulate on the surface of charcoal.

When both adsorption and absorption occur simultaneously, it is known as sorption. e.g. When a chalk is dipped in ink, the ink molecules are adsorbed at the surface of the chalk while the solvent of the ink goes deeper into the chalk due to absorption.

The process of removal of an adsorbed substance from a surface on which it was adsorbed is called desorption.

When the iron articles are coated with metals like chromium or zinc, we can prevent them from rusting.

It is made up of calcium phosphate. It starts corroding due to acid formed in mouth. The food particles which are left in mouth form acids which cause tooth decay. Toothpaste and tooth powder are basic and neutralise acid formed in mouth which prevents tooth decay.

 Sodium hydrogen carbonate.

NH₃ +CO₂ +H₂O + NaCl→ NaHCO₃ +NH₄Cl

NaCO₃ + CO₂ +H₂O → 2NaHCO₃

It is used as an antacid.

Bromine non-metal is a liquid at room temperature.

At present about 80 metals are known to us.

There are 92 elements naturally occurring.