Explore topic-wise InterviewSolutions in Current Affairs.

(a) Relief rainfall in Tamil Nadu (Palni and Shevaroy hills) is beneficial for the millets and rice crops.

(b) Cyclonic rainfall in Punjab during winter is highly useful for rabi crops in Punjab, Haryana and Western Uttar Pradesh.

(c) Mango showers on the Kerala coast are early Pre-monsoon showers before the south-west monsoons which are good for the mango trees.

Rainfall caused by the Mediterranean cyclones in winter is known as Mavath in regional language.

(b) From land to sea

The lowest air pressure in summer is found in the Thar desert of India.

During the winter season, due to movement of the belt of west winds towards the equator, a specific front region develops in the Mediterranean region. In this, the strong, cold and dry winds of Europe and central – Asia combine with the humid and warm winds on the northern border of the Mediterranean belt and near the Persian Gulf. The conjunction of these two winds with different nature results into the origination of the Mediterranean cyclones.

• Districts of Tamil Nadu Partly / fully located on Eastern Ghats and Western Ghats.
• Districts on Eastern Ghats: Vellore, Thiruvannamalai, Salem, Nammakal, Trichirapalli, Perambalur.
• Districts on Western Ghats: Nilgiris, Kanyakumari, Dindigul, Virudhunagar.

Foreigners who transacted business were known as Yavanars. Arabs who traded with Tamil were called ‘Jonagar’. Pattinappalai praised Kaveripumpattinam as a city where various foreigners of high civilization speaking different languages assembled to transact business with the support of the then Kingdom.

Many ports were developed during the Sangam period. Kaveripumpattinam was the chief port of the Kingdom of Cholas while Nagapattinam, Marakannam, Arikamedu, etc., were other small ports on east coast. Similarly, Pandiyas developed Korkai, Saliyur, Kayal, Marungaurpattinam and Kumari for foreign trade. The State Govertments installed check posts to collect customs along the highways and the ports.

The factors that affect climate are called climatic controls.

Mavath takes place due to Mediterranean cyclonic winds that blow from surface to sea in India.

The Indian climate shows diversities. The controlling and effecting factors of Indian climate are:

1. Height from the sea level. 

2. Distance from sea. 

3. Distance from equator line. 

4. Location of mountains. 

5. Direction of mountains. 

6. Direction of winds. 

7. High level air transmission. 

8. Amount of cloudiness. 

9. Coverage of vegetation. 

10.Oceanic currents.

13 Districts – Thiruvallur, Chennai, Kaneheepuram, Villupuram, Cuddalore, Tiruvarur, Nagapattinam, Thanjavur, Pudukottai, Ramanathapuram, Thoothukudi, Tirunelveli and Kanyakumari are the coastal districts.

Big cities like Poompuhar had the ‘Maruvurappakam’ (inland town) and ‘Pattinapakkam’ (coastal town), had market and bazaars where many merchants met one another for the purpose of selling or buying different kinds of commodities and food stuff. Port towns like Tondi, Korkai, Puhar and Muziri were always seen as busy with marts and markets with activities related to imports and exports. In such a brisk trade, people of the coastal region, engaged themselves in coastal trade and developed their intercontinental trade contacts.

They were engaged in different kinds of fishing pearls, and conches and produced salts and built ships. Boats like ‘Padagu’ , ‘Thimil’ , ‘Thoni’ , ‘Ambu’ , ‘Odampunai’ , etc., were used to cross rivers for domestic trade while ‘Kalam’ , ‘Marakalam’ , ‘Vangam’ , ‘Navai’ , etc., were used for crossing oceans for foreign trade.

The climate of India is affected by the movement of upper air currents in the atmosphere above 12,000 m called ‘Jet Streams’.

The factors that affect climate are called climatic controls. 

These include 

• Latitude 
• Land-water relationship 
• Relief and 
• Upper air circulation.

The difference between the temperature of day and night and that of summer and winter is not much. This is known as ‘equable climate’.

Most of the rainfall in India occurs due to the monsoon winds, therefore Indian climate is called monsoon type.

The Indian Meteorological Department divides Indian monsoon period into two parts: 

1. North – Eastern or Winter Monsoon. 

2. South – Western or Summer Monsoon.

Dusty, hot and dry winds that blow in north – western India during summer season are known as Loo.

C) Kanyakumari lies in tropical belt

As the Earth started to take shape from a fire bail to a planet, many gases were released.

These gases did not escape into outer space because of the Earth’s gravitational pull, and it still holds them back.

The climate of India is strongly influenced by the monsoon winds. The sailors who came to India during the olden days noticed the regular periodic reversal of winds. They used these winds to sail towards the Indian coast. Arab traders named this seasonal reversal of wind system ‘monsoon’. 

1. The monsoon forms in the tropical area at approximately between 20°N and 20°S latitudes. 

2. The heating of land creates low pressure on the landmass of Indian subcontinent. 

3. Southwest monsoon ‘on set’ reaches Kerala and gives rain to Western ghats and Northeast India except in the Coromandel coast. 

4. It is operated in two branches, Arabian sea branch and Bay of Bengal branch.

5. Retreat of the monsoon is marked by clear skies and rise in temperature. 

6. Lower pressure conditions move to Bay of Bengal by early November. 

7. Bulk of the rainfall of the Coromandel coast is derived from depressions and cyclones.

Correct option is B) Burst

The Arabian Sea branch and the Bay of Bengal branch.

C) Only 1 is correct

Temperature of two places located on the same latitude my be different due to difference in their heights.

D) part of North-East trade winds

Bursting monsoon: The pre-monsoon showers towards the end of the summer season in the Deccan Plateau.

The bulk of annual rainfall in India is received from the southwest monsoon.

C) Withdrawal of South West monsoon

India’s climate is controlled by various factors i.e., direction of monsoon winds, altitude (height from sea level), distance of sea, latitude (distance from equator), location of mountains and excessive atmospheric pressure.

Monsoon winds 

Climate of country is determined by various factors like Latitude, Relief, Land water relationship and upper air circulation. Climate in India is influenced by monsoons. The Arab traders named the term monsoon. The monsoons in the tropical area are strong as low pressure forms here. The Southeast monsoon winds from the Southern hemisphere carry moisture as they flow over the Indian ocean and towards the equatorial low-pressure zones. After crossing the equator, these winds deflect towards the low pressure formed in the Indian sub-continent. The heating of land creates low pressure on the land mass of Indian subcontinent, especially over central India and the Gangetic plain. Along with this, the Tibetan plateau gets intensely heated and causes strong vertical air currents and the formation of low pressure over the plateau at above 9 kms altitude.

They then flow as the southwest monsoon. The Indian peninsula divides them into two branches – the Arabian Sea branch and the Bay of Bengal branch. The Bay of Bengal branch strikes the Bengal coast and the southern face of the Shillong plateau. Then, it gets deflected and flows westward along the Gangetic valley. The Arabian Sea branch arrives at the west coast of India and moves north ward. Both the branches reach India by the beginning of June, which is known as the ‘onset of monsoon’. They gradually spread over the entire country in four to five weeks. The bulk of annual rainfall in India is received from south-west monsoon. The amount of rainfall is very high along the west coast due to the Western ghats, and in north-east India due to the high peaked hills. Tamil Nadu coast (Coromandel), however, remains mostly dry during this season as it is in the rain shadow area of the Arabian Sea branch and is parallel to the Bay of Bengal branch.

The low pressure conditions which once prevailed over north-western India move far South to the centre of the Bay of Bengal by early November. During this period, cyclonic depressions are common which originate over the Andaman area. These tropical cyclones are often very destructive. The thickly populated deltas of the Godavari, Krishna and Cauveri are their targets. No year ever goes disaster-free. Occasionally, these tropical cyclones visit Sundarbans and Bangladesh too. Bulk of the rainfall of the Coramandel Coast is derived from depressions and cyclones.

The Arabian Sea branch arrives at the west coast of India and moves northward. Both the Arabian Sea and Bay of Bengal branches reach India by the beginning of June, which is known as ’Onset of monsoon1.

Four factors which influence the climate are: 

1. Altitude (Height above sea-level) 

2. Latitude (Distance from equator) 

3. Distance from the sea 

4. Direction of winds

The monsoon forms in the tropical area approximately between 20eN and 208S latitudes,

Correct Answer is: (c) Hot-Moist

Correct Answer is: (d) six

1. Single cross over: Formation of single chiasma and involves only two chromatids out of four. 

2. Double cross over: Formation of two chiasmata and involves two or three or all four strands. 

3. Multiple cross over: Formation of more than two chiasmata and crossing over frequency is extremely low.

Correct Answer is : T.H. Morgan

Temperature, X-rays, Gamma rays and UV rays.

(c) Ascorbic acid

(a) Ethyl methane sulphonate (EMS) 

(b) Mustard gas 

(c) Magnous salt 

(d) Formaldehyde

The chromosome number of somatic cells changes due to addition or elimination of individual chromosome or basic set of chromosomes. This condition in known as numerical chromosomal aberration or ploidy.

The Arabian Sea Monsoon branch strikes the Western Ghat and sheds about 250 to 300 cm of rainfall. As they fall in rain shadow area, they receive very low rainfall. Its Nagpur branch moving through Narmada-Tapti valley joins the Bay of Bengal. Another sub-branch reaches directly the Western Himalayas, passing through Gujarat, Rajasthan, etc. Rajasthan receives very little rainfall because of its location parallel to the Aravalli ranges.

The Aravalli range divides Rajasthan on the basis of rainfall, because more rainfall occurs in its eastern part, while less rainfall occurs in its western part. But because of its less height, it does not play any role in getting rainfall. Due to its parallel of Aravallis, the branch of the Arabian Sea proceeds by its sides towards the north. With no obstruction, precipitation is minimal through this branch.

The fast blowing winds of a steady velocity, moving in a narrow zone of the upper atmosphere, are called the Jet Streams.

Jet streams flow over the western and the central Asia.

(b) Gamma radiation

On the basis of area the Jet Streams are named as: 

1. Tropical Eastern Jet 

2. Semi-Tropical Western Jet.