Explore topic-wise InterviewSolutions in Current Affairs.

The irrigation requirements of a crop depend on the nature of soil in which the crop is grown. There are two types of soil- sandy soil and clayey soil. Sandy soil is highly porous having highly permeability. So, the water quickly percolates down to the soil and crop plants standing in the sandy soil, are not able to get adequate amount of water. Thus, crop cultivated in sandy soil need more frequent irrigation of water. On the other hand, the clayey soil is much less permeable than sandy soil due to which it can retain water for a much longer time. Thus, crop cultivated in clayey soil can absorb adequate amount of water. Hence, the crop grown in a clayey soil need irrigation less frequently.

1. sprinkler system 

2. Drip system

(a) crop 

(b) preparation 

(c) nutrients; water 

(d) float 

(e) nitrogen 

(f) irrigation 

(g) weeds 

(h) neem 

(i) coastal

         A                                   B 

(i) Kharif crops                (e) Paddy and maize 

(ii) Rabi crops                (d) Wheat, gram, pea 

(iii) Chemical fertilisers (b) Urea and super phosphate 

(iv) Organic manure       (c) Animal excreta, cow dung, urine and plant waste

D. transplantation 

Paddy, tomatoes and chillies are grown by transplantation.

 (a) The same kind of plants grown and cultivated on a large scale at a place is called crop. 

(b) The first step before growing crops is preparation of the soil. 

(c) Damaged seeds would float on top of water. 

(d) For growing a crop, sufficient sunlight and water and nutrients from the soil are essential

Correct option is (c) A traditional approach to management can be successfully applied to the problems of a modern organisation

Correct option is (a) classical perspective

Correct option is (d) are self-motivated and self-directed toward achieving organizational goals.

Correct option is (c) Frederick Taylor

Garbage: Waste of vegetables, fruits, food, and other domestic materials.

Decompose: Broken down of organic matter physically and chemically by bacterial or fungal action or rot.

Conjunctivitis: Conjunctivitis is swelling (inflammation) or infection of the membrane lining the eyelids (conjunctiva).

The main symptom of goiter is a very big and bulging throat.

Insulin hormone deficiency causes diabetes.

The deficiency of thyroxine hormone in body causes goiter.

The deficiency of thyroxine hormone in adults causes a disease called goiter. The main symptom of disease is that the neck of the person suffering from Goitre appears to be swollen.

Acetic acid (CH₃COOH) is a weak acid and belongs to the family of carboxylic acids. 

Physical Properties: 

Acetic acid exists in liquid state at room temperature. Pure acetic acid has a melting point of 290K and often freezes when kept in cold climates. 

Chemical Properties: 

(a) Reaction with alcohol: 

Acetic acids react with alcohols in the presence of an acidic medium to form esters. Esters are sweet smelling substances and are often used in perfumes and as flavouring agents.

CH₃COOH + R-OH \(\overset{Acid}\longrightarrow\) CH₃COOR + H₂O

(b) Reaction with base: 

Like other acids, acetic acid reacts with base to form salt and water. The reaction is called neutralization reaction. 

CH₃COOH + NaOH (base) → CH₃COONa (Salt) + H₂O

(c) Reaction with carbonates and bicarbonates:

Acetic acid reacts with carbonates and bicarbonates to form salt, carbon dioxide and water.

2CH₃COOH + Na₂CO₃ → 2CH₃COONa + CO₂↑ + H₂O

CH₃COOH + NaHCO₃ → CH₃COONa + CO₂↑ + H₂O

• Lichens secrete organic acids like Oxalic acids which corrodes the rock surface and helps in weathering of rocks, acting as pioneers in Xerosere. 
• Lichens are sensitive to air pollutants and are considered as pollution indicators.
• Cladonia rangiferina (Reindeer moss) is used as food for animals living in Tundra regions.
• Usnic acid produced from lichens show antibiotic properties. 

Ribosomes are involved in protein synthesis. Starch is not produced by ribosomes as plastids are involved in the production of starch.

Because ribosome help in the production of protein molecules and enzymes for the cell to work efficiently. 

But hormone and starch molecule formation is not carried out by ribosomes.

• Mycorrhizae helps to derive nutrition in Monotropa, a saprophytic angiosperm.
• Improves the availability of minerals and water to the plants. 
• Provides drought resistance to the plants. 
• Protects roots of higher plants from the attack of plant pathogens. 

• They are most primitive prokaryotes. 
• They are found in extreme environmental conditions. Eg: Hot springs. 
• Unique feature is presence of lipids like glycerol and isopropyl ethers in their cell membrane. 
• Hence the membrane shows resistance against cell wall antibiotics. Eg: Methanobacterium. 

• As soon as the phage injects its linear DNA into the host cell, it becomes circular and integrates into the bacterial chromosome by recombination.
• The integrated phage DNA is now called prophage. 

• Property of self-regulation and tendency to maintain a steady state within an external environment which is liable to change is called Homeostasis. It is essential for the living organisms. 

• Archaebacteria are primitive prokaryotes and are adapted to live in extreme environment like hot springs, high salinity and low pH. E.g., Thermoplasma. 

• In the lysogenic cycle of a phage, the integrated phage DNA with bacterial DNA is called prophage.

• Cholera, Typhoid, Tuberculosis and Leprosy. 

• Anthrax, Brucellosis, Bovine tuberculosis and black leg. 

Typhoid is caused by Salmonella typhi. TB is caused by Mycobacterium tuberculosis.

• They are prokaryotes. 
• The genetic material is called nucleoid and lacks nuclear membrane. 
• They reproduce by fission. (Binary or Multiple) 

Plasmodesmata is a connection between cell walls of two adjacent plant cells.

Some of the cells (eg parenchyma, sclerenchyma, sieve plates, vessels, trachids cells) remain unthickened. The unthickened parts develop pits which are of two types –

(A) Simple pits – They are found in between the cell wall of adjacent cells of sieve tubes, parenchyma, companion cells etc. These pits are round & cylindrical. They allow the exchange of water and dissolved substances across the membrane. The diameter of simple pits remain uniform and the pit cavity trpens in the lumen of the cell..

(B) Bordered pit – The bordered pits are more complex than the simple pits. In this case, the secondary wall border over the cavity of the pits. Hence, the pit opening become narrow than the pit diameter. In certain cases, the pit aperture are lenticular. The pit membrance of bordered pit develops an oval thickening in the middle. It is called torus. Pit membrane is flexible.

The answer is (c) Pectates of Ca & Mg

The answer is (c) Carbohydrates

Intake of substances into the cytoplasm.

Robertson (1958) propounded unit membrane concept. According to it, one (single) unit membrane consists of three layers (2 proteins +1 phospholipid) and its thickness is 75A° (70 to 80A°).

The answer is Secondary’ cell wall.

The answer is Polysaccharides (Chitin, cellulose, pectin).

The answer is 75A° (70 to 80A°).

The answer is Robertson (1958).

Modifications of plasma membrane:

In animal cells, the plasma membrane forms certain structures to perform special functions which are as follows –
(i) The epithelial cells form finger – like processes called microvilli to provide increase surface for absorption.
(ii) It forms desmosomes between adjacent cells that consists of tono fibrils.
(iii) In some cells, it forms interdigitations.

Functions of Plasma Membrane:

1. It provides shape & size to the cells.
2. It protects the cell organelles.
3. It performs transportation of the substances which is of two types-

• Passive transport – It involves movement of the substances from their high to low concentration. It does not require energy.
• Example – Diffusion, Osmosis.
• Active transport – It involves movement of the substances against concentration gradient i.e. from low to high concentration. It takes place at the cost of energy (ATP). In this process carrier proteins (Permeases) act as carrier.

1. It helps in cell adhesion.
2. It bears respiratory enzymes in prokaryotes (e.g. bacteria)
3.  It performs endocytosis. The intake of substance with the help of plasma membrane is called as endocytosis. The intake of solid substance is termed as phagocytosis and the intake of liquid substances is called as pinocytosis.
   (vii) It performs exocytosis (expulsion of waste products from the cell).

Thickening takes place in the cell wail during formation of secondary wall on the inner side of the primanry wail, This type of thickening depends upon the nature of the cell wall. This thickening takes place due to deposition of hard substances such as lignin. cellulose, hemicelluloses. suberin etc. The thickening is found in the cells of certain parts like pericycle, phloem. xylem etc.

Some of the cells (cg parenchvina, sclerenchvma. sieve plates, vessels. trachids cells) remain unthickened. The unthickened parts develop pits which are of two types –

• Simple pits – The are found in between the cell wall of adjacent cells of sieve tubes, parenchyma. companion cells etc. These pits arc round & cylindrical. They allow the exchange of water and dissolved substances across the membrane, The diameter of simple pits remain uniform and the pit cavity trpens in the lumen of the cell.
• Bordered pit – The bordered pits are more complex than the simple pits. In this case. the secondar’ wall border over the cavity of the pits. Hence, the pit opening become narrow than the pit diameter. In certain cases, the pit aperture are lenticular The pit membrance of bordered pit develops an oval thickening in the middle. It is called torus. Pit membrane is flexible.

The liquid in cell put pressure on the pit membrane and the pit membrane pushes the torus. Thus the toruse closes the bordered pit. Hence, it acts as a valve.These are found in the vessles, tracheids and fibres of xylem.

(i) It provides shape & size to the cells.

(ii) It protects the cell organelles.

Thickening takes place in the cell wall during formation of secondary wall on the inner side of the primary wall. This type of thickening depends upon the nature of the cell wall. This thickening takes place due to deposition of hard substances such as lignin, cellulose, hemicelluloses, suberin etc.

The answer is (c) Endocytosis

The answer is (c) Sieve tubes

The organisms isolated from pleural fluid of cattle Mycoplasma. 

The answer is (a) 3000 glucose molecules