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Access Class 11 Maths NCERT Solutions Chapter 12 Introduction to three Dimensional Geometry Ex 12.2, contains solutions for all Exercise 12.2 Class 11 questions.

Introduction to three Dimensional Geometry Class 11 NCERT Solutions Maths Chapter 12 Exercise 12.2

NCERT Solutions for Class 9 Social Science Geography Chapter 1 India-Size and Location

These Solutions are part of NCERT Solutions for Class 9 Social Science. Here we have given NCERT Solutions for Class 9 Social Science Geography Chapter 1 India-Size and Location.

Question 1.
Choose the right answer from the four alternatives given below.

(i) The Tropic of Cancer does not pass through
(a) Rajasthan
(b) Odisha
(c) Chhattisgarh
(d) Tripura
Ans. (b) Odisha.

(ii) The easternmost longitude of India is
(a) 97°25′ E
(b) 68°7′ E
(c) 77°6’E
(d) 82°32’E
Ans. (a) 97°25′ E

(iii) Uttarakhand, Uttar Pradesh, Bihar, West Bengal and Sikkim have common frontiers with
(a) China
(b) Bhutan
(c) Nepal
(d) Myanmar
Ans. (c) Nepal.

(iv) If you intend to visit kavarati during your summer vacations, which one of the following Union Territories of India you will be going to
(a) Puducherry
(b) Lakshadweep
(c) Andaman and Nicobar
(d) Daman and Diu
Ans. (b) Lakshadweep.

(v) My friend hails from a country which does not share land boundary with India. Identify the country.
(a) Bhutan
(b) Tajikistan
(c) Bangladesh
(d) Nepal
Ans. (b) Tajikistan

Question 2.
Answer the following questions briefly.

(i) Name the group of islands lying in the Arabian Sea.
Ans. Lakshadweep islands lie in the Arabian Sea.

(ii) Name the countries which are larger than India.
Ans. Russia, Canada, U.S.A, China, Brazil, and Australia are the countries that are larger than India.

(iii) Which island group of India lies to its south-east?
Ans. Andaman and Nicobar island group lie to the south-east of India.

(iv) Which island countries are our southern neighbours?
Ans. Sri Lanka and Maldives are the two island countries that are our southern neighbours.

Question 3.
The sunrises two hours earlier in Arunachal Pradesh as compared to Gujarat in the west but the watches show the same time. How does this happen?
Answer:
The latitudinal and longitudinal extent of the mainland is about 30°. Despite this fact, the east-west extent appears to be smaller than the north-south extent. From Gujarat to Arunachal Pradesh there is a time lag of two hours. Hence, time along the Standard Meridian of India (82°30’E) passing through Mirzapur (in Uttar Pradesh) is taken as the standard time for the whole country. The latitudinal extent influences the duration of the day and night, as one moves from south to north.

Question 4.
The central location of India at the head of the Indian Ocean is considered of great significance. Why?
Answer:
The location of India at the head of the Indian Ocean has helped India in establishing close contacts with West Asia, Africa, and Europe from the western coast and eastern Asia from the eastern coast.

Map Skills

Question 1.
Identify the following with the help of map reading.
(i) The Island groups of India lying in the Arabian Sea and the Bay of Bengal.
(ii) The countries constituting the Indian Subcontinent.
(iii) The States through which the Tropic of Cancer passes.
(iv) The northernmost latitude in degrees.
(v) The southernmost latitude of the Indian mainland in degrees.
(vi) The eastern and the western-most longitude in degrees.
(vii) The place situated on the three seas.
(viii) The strait separating Sri Lanka from India.
(ix) The Union Territories of India.
Answer:

Hope given NCERT Solutions for Class 9 Social Science Geography Chapter 1 are helpful to complete your homework.

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Access Class 12 Maths NCERT Solutions Chapter 9 Differential Equations Ex 9.3, contains solutions for all Exercise 9.3 Class 12 questions.

Differential Equations Class 12 NCERT Solutions Maths Chapter 9 Exercise 9.3

Here we are providing NCERT Solutions for Class 12 English Flamingo Chapter 5 Indigo. Students can get Class 12 English Indigo NCERT Solutions, Questions and Answers designed by subject expert teachers.

Indigo NCERT Solutions for Class 12 English Flamingo Chapter 5

Indigo NCERT Text Book Questions and Answers

Indigo Think as you read 

Question 1.
Choose the correct options.
(a) Rajkumar Shukla was
(i) a sharecropper
(ii) a politician
(iii) a delegate
(iv) a landlord
Answer:
(i) a sharecropper

(b) Rajkumar Shukla was
(i) poor
(ii) physically strong
(iii) illiterate
(iv) poor
Answer:
(iii) illiterate

Question 2.
Why is Rajkumar Shukla described as being “resolute”?
Answer:
Rajkumar Shukla was a “resolute” man. He was determined to take Gandhi to Champaran, to champion the cause of the poor sharecroppers. When Gandhi said that he had a prior arrangement to go to Kanpur and to other parts of India, Shukla went everywhere with him. He also followed Gandhi to his ashram near Ahmedabad and stayed there for weeks and begged him to visit Champaran. Gandhi finally agreed to go with him, and asked him to take him to Champaran from Calcutta.

Question 3.
Why do you think the servants thought Gandhi to be another peasant?
Answer:
Shukla took Gandhi to the house of Rajendra Prasad who was out of town, but the servants knew of Shukla as a poor farmer. They, therefore, presumed Gandhi to be another peasant.

Question 4.
List the places that Gandhi visited between his first meeting with Shukla and his arrival at Champaran.
Answer:
Gandhi met Shukla in Lucknow. From there, Gandhi went to Kanpur and to other parts of India. Then Gandhi returned to his ashram near Ahmedabad. He later went to Calcutta and from there to Patna in Bihar. Gandhi then decided to go to Muzzafarpur, which was en route to Champaran, and finally to Champaran.

Question 5.
What did the peasants pay the British landlords as rent? What did the British subsequently want and why?
What would be the impact of synthetic indigo on the prices of natural indigo?
Answer:
Most of the cultivable land in the Champaran district was divided into large estates owned by Englishmen where Indian tenants worked. The chief commercial crop was indigo. The landlords forced the tenants to plant fifteen per cent of their land with indigo and give up the whole indigo harvest as rent. The landlords had learned how Germany had developed synthetic indigo. Thus, they forced the sharecroppers to sign agreements to pay them compensation to be released from the fifteen per cent arrangement.

The sharecroppers, who refused this arrangement, engaged lawyers, and to counter them, the landlords hired thugs. But, when the information about synthetic indigo reached the peasants who had signed the agreement, they wanted their money back.

Question 6.
The events in this part of the text illustrate Gandhi’s method of working. Can you identify some instances of this method and link them to his ideas of satyagraha and non-violence?
Answer:
Gandhi visited the secretary of the British landlords’ association to collect information about his cause of assisting the indigo sharecroppers. They refused to give information to an outsider but Gandhi stated emphatically that he was no outsider.

When the British official commissioner of the Tirhut division asked Gandhi to leave Tirhut, he refused. Even when the messenger served him with an official notice to quit Champaran, Gandhi signed a receipt for the notice and wrote on it that he would disobey the order. He disregarded the order to leave, “not for want of respect for lawful authority, but in obedience to the higher law of our being, the voice of conscience”.

He organised a gathering of peasants at Motihari, around the courthouse, which was the beginning of their liberation from fear of the British. Nevertheless, Gandhi cooperated with the officials to regulate the crowd. He was polite and friendly. He gave them concrete proof that their might could be challenged by Indians.

He inspired the lawyers to fight the injustice meted out to the sharecroppers. He organised them in pairs and formulated the order in which each pair was to court arrest. He demonstrated by his own example how peaceful protest and non-violence could be useful tools to achieve results. He used similar philosophy when he carried out satyagraha later in his political career.

Question 7.
Why did Gandhi agree to a settlement of 25 per cent refund to the farmers?
Answer:
After the inquiry committee report, the peasants expected the refund of the entire sum of money but Gandhi asked for only fifty per cent of the sum. However, when the representative of the planters offered to refund twenty-five per cent, Gandhi accepted it.

Gandhi felt that money was less important at that stage. What was more important was that for the first time, the landlords had been made to surrender their self-esteem. Moreover, the peasants realized that they had rights as citizens and the agitation taught them their first lesson in courage.

Question 8.
How did the episode change the plight of the peasants?
Answer:
The episode made the landlords surrender their self-esteem. Till then, the planters had behaved as lords, above the reach of law. The peasants were made to realise how they could fight for their rights. It liberated them from their fear of the British.

 Indigo Understanding the text

Question 1.
Why do you think Gandhi considered the Champaran episode to be a turning point in his life?
Answer:
Gandhi went to Champaran in 1917 and it was then that he decided on insisting that the British leave India. It was there that he raised his voice against the injustice of the landlord system in Bihar and also freed the peasants from their fear. First, he defied the secretary of the British landlords’ association, who refused to give information to an “outsider”. Next, he refused to leave Tirhut division in which the Champaran district lay despite being told to do so. He also arranged a gathering of peasants in huge numbers which was the beginning of their freedom from fear of the British.

The officials felt powerless without Gandhi’s cooperation. This was his proof that the power of the Englishmen could be challenged by the Indians.The peasants realized that they had rights and it was their first lesson in courage. Soon, within a few years, the British planters returned the estates to the peasants. This was the end of indigo sharecropping in India.

Through the Champaran incident, Gandhi declared for the first time that the British could not order Indians in their own country. He, through personal example, was able to motivate the masses into civil disobedience and teach them to be self-reliant.

Question 2.
How was Gandhi able to influence lawyers? Give instances.
Answer:
The Muzzafarpur lawyers called on Gandhi in Champaran to brief him about their cases and talked about the fees they charged the sharecroppers. Gandhi reprimanded the lawyers for charging the poor sharecroppers hefty sums of money. He also said that freedom from fear would help the sharecroppers more than merely taking such cases to court.

When Gandhi courted arrest, he assembled Rajendra Prasad, Brij Kishor Babu, Maulana Mazharul Hut and several other prominent lawyers from Bihar. He asked them what they would do if he was sentenced to prison. A senior lawyer replied that they had come to him for advise and help, and if he went to jail, there would be nobody to advise them. They felt that if Gandhi being a complete stranger was prepared to go to prison for the sake of the peasants, then it would be a shameful desertion if they, not only as residents of the adjoining districts but also as those who claimed to have served these peasants, should go home. They went back to Gandhi and told him they were ready to follow him into jail.

Question 3.
What was the attitude of the average Indian in smaller localities towards advocates of “home rule”?
Answer:
Gandhi, on his way to Champaran, decided to meet J B Kripalani of the Arts College in Muzzafarpur, whom he had seen at Tagore’s Shantiniketan school. The train reached there at midnight on 15 April 1917. Gandhi stayed there for two days in the home of Professor Malkani, a teacher in a government school. This was an extraordinary thing in those days. It was highly unlikely that a government professor would give shelter to a rebel like him, for fear of termination from service by the government. In smaller regions, the Indians were afraid to show compassion for the supporters of home-rule.

Question 4.
How do we know that ordinary people too contributed to the freedom movement?
Answer:
The author mentioned several ordinary people who contributed to the home-rule movement in different capacities.
On his way to Champaran, in Muzzafarpur, Gandhi stayed in Muzzafarpur for two days in the home of Professor Malkani, a teacher in a government school. For a government servant, Malkani, showed a great deal of courage by giving shelter to a person who was fighting for home-rule.

In Champaran, at the railway station, there was a crowd to greet Gandhi. Motihari was also teeming with peasants, though they did not know about Gandhi’s achievements. But, their gathering in huge numbers was the beginning of their freedom from fear of the British. This was the proof that the power of the British could be challenged by Indians. The lawyers, after meeting Gandhi, assured him that they would court arrest. Civil disobedience—a movement of the people—won for the first time in modem India.

Gandhi and the lawyers then conducted a detailed enquiry into the grievances of the farmers. They prepared cases for about ten thousand peasants and collected relevant documents. The masses helped Gandhi, who was not satisfied with only political or economic solutions. What concerned him was the cultural and social backwardness in Champaran. He requested teachers to educate the masses. Two young men Mahadev Desai and Narhari Parikh and their wives, volunteered to do this work. Several more including Devadas, Gandhi’s youngest son, joined in. Kasturba Gandhi, too, taught personal cleanliness and community sanitation. Volunteers from amongst the masses rendered unflinching support.

 Indigo Talking about the text

Discuss the following.

Question 1.
“Freedom from fear is more important than legal justice for the poor.” Do you think that the poor of India are free from fear after Independence?
Answer:
As the rich and well-heeled made preparations to ring in the new year in style across a new, shining India, a wave of revulsion swept through the country after the report of mass killings in a sleepy, poor housing area. This was in Nithari, no more than eighteen miles from the capital, Delhi, and in one of India’s most prosperous and upcoming districts, Noida. Violent death involving such larger numbers is not so rare in India, especially where the poor are concerned. Nithari provoked a different response, because this case illustrates best the most barbaric and basic truth about the Indian state.

The incident reveals how the country’s poor is still under the threat of injustice. It is one example of how the poor and weak have just no place in the Indian system. It also deeply concerns how the Indian media has been sucked into covering the relatively more mundane, but sensational issues. The media had heard of reports of children disappearing but no one took the trouble to take up the issue. The inefficiency of the police is just a cover- up as this could never have happened if the victims belonged to a rich or middle-class neighbourhood.

Speaking to a BBC Hindi service show, one of India’s most celebrated police officers, Kiran Bedi, said that the Nithari case was an example of how, for the common man in the country, there is no police or justice system. “The system needs to be completely overhauled and wide-ranging reforms are needed in the police structure,” she said.

But only police reforms are insufficient, the entire system and attitudes desperately need to be reformed. India’s economic prowess and potential is much talked about but can we say with the same degree of optimism that there will not be another Nithari, when India does realise its dreams?

Question 2.
The qualities of a good leader.
Answer:

• Integrity
• Self knowledge
• Commitment
• Consistency of purpose
• Willingness to admit a mistake
• Ability to listen
• Openness to change
• Decisiveness
• Ability to go the extra mile
• Enthusiasm
• Awareness
• Positive Communication
• Dynamism
• Impartial approach

 Indigo Working with words

Question 1.
List the words used in the text that are related to legal procedures.
For example: deposition
List other words that you know that fall into this category.
Answer:
The words used in the text that are related to legal procedures are:
proceedings, brief, cases, agreements, notice, summons, prosecutor, pleading, pronounce sentence, bail, court, reconvened, judgment, sentenced, entreaty, evidence, defenders, trial, deposition, etc.

Indigo Extra Questions and Answers

Indigo Short Answer Questions

Answer the following briefly.

Question 1.
When and where did Louis Fischer first meet Gandhi? What did they talk about?
Answer:
Louis Fischer served as a volunteer in the British Army between 1918 and 1920. He wrote a book on Gandhi named ‘The Life of Mahatma Gandhi’. He met Gandhi when he first visited him, in 1942, at his ashram in Sevagram, in central India. That was the time when Gandhi told him how he had decided to urge the departure of the British from India, in 1917.

Question 2.
Why was Gandhi in Lucknow in 1916? What happened there that was to change the course of Indian history?
Answer:
In December 1916, Gandhi had gone to the annual convention of the Indian National Congress in Lucknow, where there were 2,301 delegates and many visitors. There, he met with a poor peasant, Rajkumar Shukla from Champaran. Shukla pleaded with Gandhi to visit his hometown and brought to Gandhi’s notice the miserable plight of the indigo farmers. This fuelled his campaign in 1917 to drive out the British from India.

Question 3.
How did Rajkumar Shukla decide to meet Gandhi?
Answer:
Rajkumar Shukla was one of the many sharecroppers of Champaran. He was illiterate but resolute. He had been advised to go to the Congress session to complain to Gandhi about the injustice of the landlord system in Bihar. He was told that Gandhi could help them. He followed Gandhi through his travels and stayed with him in the ashram till Gandhi promised to accompany him for the cause of the poor peasants.

Question 4.
What episode in Patna showed Gandhi the existence of a rigid caste system?
Answer:
Shukla took Gandhi to Patna. He led him to the house of a lawyer, Rajendra Prasad, who was out of town, but the servants recognized Shukla as a poor indigo peasant. They let him and his companion, Gandhi, stay on his premises but forbade them to draw water from the well. They presumed Gandhi to be another peasant and treated him as an untouchable. Gandhi was made aware of the menace of the caste system.

Question 5.
What was Gandhi’s first step to help Rajkumar Shukla and the indigo sharecroppers?
Answer:
Gandhi decided, first, to go to Muzzafarpur en route to Champaran, to obtain more information about the prevailing conditions of the indigo sharecroppers. He, consequently, sent a telegram to Professor J.B. Kripalani of the Arts College in Muzzafarpur, whom he had seen at Tagore’s Shantiniketan school requesting a meeting.

Question 6.
Why was Gandhi’s stay with Professor Malkani an astonishing experience?
Answer:
Gandhi stayed for two days in the home of Professor Malkani, a teacher in a government school. It was unlikely for a government professor to provide shelter to a rebel like Gandhi for fear of termination from service by the government. In smaller localities, the Indians were afraid to show sympathy for the advocates of home-rule. Professor Malkani’s defiance to fall in line revealed his sympathy for the movement.

Question 7.
Why did Gandhi decide against taking the cases of the sharecroppers to the court of law?
Answer:
When Gandhi reached Muzzafarpur, the lawyers told him about their cases and revealed how they charged ‘ the peasants hefty sums of money as fees. Gandhi reprimanded the lawyers and discouraged them from charging the sharecroppers. He said taking such cases to the courts would do no good. He felt that because the peasants were so crushed and fear-stricken, the law courts were useless. The real relief to them would be to free them from fear.

Question 8.
How was Gandhi’s visit to Champaran viewed by the peasants?
Answer:
Gandhi decided to visit Muzzafarpur, en route to Champaran, to obtain more information about the situation at Champaran. The news of Gandhi’s arrival and his initiative spread through Muzzafarpur and reached Champaran. Though they did not know of Gandhi’s record in South Africa, they gathered in multitudes to see him. These sharecroppers from Champaran began arriving on foot to see the man who had come to champion their cause.

Question 9.
What was the problem of the sharecroppers in Champaran?
Answer:
Most of the agricultural land in the Champaran district was divided into large estates that were owned by Englishmen. They engaged Indian tenants to work on their lands. The landlords forced all tenants to plant . fifteen per cent of their holdings with indigo and surrender the entire indigo harvest as rent. With Germany developing synthetic indigo, the British duped the sharecroppers into entering an agreement where they were required to pay them compensation for being released from the fifteen per cent arrangement. Some peasants signed it, while others engaged lawyers to get their money back. The landlords hired thugs to fight them.

Question 10.
What was the stand of the Englishmen on indigo farming? What was the reaction of the peasants?
Answer:
The English landlords learned that Germany had developed synthetic indigo. They forced the sharecroppers to enter an agreement whereby they were required to pay them compensation for being released from the fifteen per cent arrangement. Many peasants signed it. Some of them resisted and engaged lawyers. The landlords hired thugs to get their way. When the information about synthetic indigo reached the peasants who had signed the agreement, they wanted their money back. They arranged for Gandhi to intervene on their behalf but he was met with resentment from the government who tried their best to dissuade him from taking up this cause, by forcing him to leave Champaran.

Question 11.
It was not easy for Gandhi to get information about the agreement with the peasants. Why?
Answer:
Gandhi first visited the secretary of the British landlords association to collect information about the agreement with the peasants, they refused to give information to an “outsider”. The British official commissioner of the Tirhut division, in which the Champaran district lay, bullied him, and advised him to leave Tirhut. Gandhi refused to leave.

Question 12.
What was the treatment meted out to Gandhi in Motihari? What was the reaction to Gandhi refusing to obey the order to quit Champaran?
Answer:
Gandhi was accompanied by several lawyers to Motihari. There he got news that a peasant had been maltreated in a nearby village. Gandhi decided to go and meet him, but on his way, the police ordered him to return to town and Gandhi agreed. He was then asked to quit Champaran but Gandhi declared that he would disobey the order.

Question 12.
On his refusal to quit Champaran, Gandhi received summons to appear in court the next day.
Answer:
He telegraphed Rajendra Prasad to come from Bihar with his influential friends. He sent instructions to the ashram. He wired a full report to the Viceroy. By morning, Motihari was full of peasants. They demonstrated around the courthouse when Gandhi was summoned to court. This was the beginning of their liberation from fear of the British. The officials felt powerless without Gandhi’s cooperation. Gandhi finally helped them regulate the crowd.

Question 13.
How did the gathering of peasants in Motihari help them tremendously?
Answer:
The peasants who had collected in Motihari did not know Gandhi’s achievements in South Africa. They knew that a Mahatma who wanted to help them was in trouble with the authorities. Their unplanned demonstration, in thousands, around the courthouse was the beginning of their freedom from fear of the British. Thus, Gandhi knew that this was a leap in the right direction and would go a long way in helping them achieve home-rule.

Question 14.
How did Gandhi’s non-cooperation affect the officials?
Answer:
The peasants demonstrated in large numbers to lend support to Gandhi outside the courthouse in Motihari. The officials felt helpless without Gandhi’s cooperation to bring the crowd under control. Gandhi cooperated with them and helped regulate the crowd. He was polite and friendly. He gave British proof of how they could be challenged by Indians. The government was bewildered. The authorities wished to consult their superiors.

Question 15.
What was Gandhi’s advice to the lawyers that made them champion peasants rights?
Answer:
The prominent lawyers told Gandhi that they had come to advise and help him. When Gandhi talked to them about the injustice to the sharecroppers, the lawyers realized that Gandhi was a complete stranger and yet he was prepared to go to prison for the peasants. On the other hand, if they, being residents of the adjoining districts, and having claimed to have served these peasants, should go home, it would be a shameful desertion. They promised to join in Gandhi’s efforts and follow him to jail to win the cause.

Question 16.
Why did Gandhi say, “The battle of Champaran is won”? Was it true?
Answer:
When the lawyers told Gandhi that they were ready to follow him into jail, Gandhi exclaimed that the battle of Champaran was won. He divided the group into pairs and decided the order in which each pair was to court arrest. Several days later, Gandhi received a written communication from the magistrate informing him that the case against him was to bedropped. This gave them their first victory against the injustice at Champaran.

Question 17.
Why did Gandhi compromise to break the deadlock between the sharecroppers and planters?
Answer:
The Lieutenant Governor appointed an official commission of enquiry into the indigo sharecroppers’ situation. Gandhi was the sole representative of the peasants. The sharecroppers thought Gandhi would ask for repayment of the money which the landlords had illegally extorted from them. However, he asked for only fifty per cent of the amount, but later agreed to a twenty-five per cent refund. He said that the refund was less important than the fact that the landlords had surrendered a part of the money and were brought down from their pedestal. The landlords were made to realize that they were not beyond the reach of law.

Question 18.
What were Gandhi’s chief concerns? How did he address them?
Answer:
Gandhi was keen to assist in the improvement of the cultural and social conditions of the villages. He appealed to teachers and other young people to act as volunteers. People were educated in personal cleanliness and community sanitation. He looked into the health conditions of the community and medicines were made available to the people.

Question 19.
Who helped Gandhi in his endeavour to uplift the backward people?
Answer:
Mahadev Desai and Narhari Parikh, two young men and their wives volunteered to serve the community of Champaran. Several others arrived from Bombay, Poona, and other distant parts of the land. Devadas, Gandhi’s youngest son, and his wife, Kasturba Gandhi, played a pivotal role in helping him fight backwardness. Primary schools were opened in six villages. Kasturba taught the ashram rules on personal cleanliness and community sanitation.

Question 20.
Why was the Champaran episode a turning point in Gandhi’s life?
Answer:
The Champaran episode was a turning point in Gandhi’s life. It was during his fight for justice for the Champaran peasants that he declared that the British could not order him about in his own country. It grew out of his attempt to alleviate the distress of large numbers of poor peasants. The Champaran episode made Gandhi launch a movement that finally drove out the British from India.

Question 21.
Gandhi was not a politician but his political principles were intertwined with the practical problems of the Indians. Justify.
Answer:
Gandhi’s political principle was aligned with the day-to-day problems of the masses. He was not loyal to his principles alone, he endeavoured to work towards the greater good of human beings. Champaran was a typical pattern of Gandhi’s politics. It did not begin as an act of defiance but as an effort to help the destitute.

Indigo Long Answer Questions

Question 1.
Rajkumar Shukla unwittingly played an important role in freeing the peasant community in India. Discuss.
Answer:
Rajkumar Shukla met Gandhi in December 1916, when he had gone to attend the annual convention of the Indian National Congress in Lucknow. He informed Gandhi about the injustice of the indigo sharecropping arrangement that preyed on the poor Champaran peasants. He informed him about the injustice of the landlord system in Bihar.

Though Rajkumar was illiterate, he was resolute to convince Gandhi to take up their cause. He accompanied Gandhi to Kanpur and other parts of India and to his ashram near Ahmedabad, and for weeks he never left Gandhi’s side. Finally, when Gandhi went to Calcutta, Rajkumar Shukla convinced him to visit Champaran.

Question 2.
Give a detailed account of the problem of sharecroppers in Champaran.
Answer:
In Champaran, most of the arable land was owned by Englishmen who had engaged Indian tenants to cultivate their lands. The landlords of the area compelled all tenants to plant fifteen per cent of their holdings with indigo, the chief commercial crop, and surrender the entire indigo harvest as rent. This was done by long-term contract. When the landlords learned that Germany had developed synthetic indigo, they forced the sharecroppers to enter into an agreement to rake in compensation to free them of their fifteen per cent arrangement. Many peasants signed it willingly. Those who resisted, engaged lawyers but the landlords hired thugs to beat them into accepting their terms. Meanwhile, the information about synthetic indigo reached the illiterate peasants, and they demanded their money back.

Question 3.
What was the first order of the British government that Gandhi refused to obey?
Answer:
In Bihar, to find out about the sharecropping arrangement, Gandhi first visited the secretary of the British
landlords’ association. The secretary refused to give information to an “outsider”. Next, the British commissioner of Tirhut asked him to leave Tirhut, which he did not. Instead, he proceeded to Motihari, accompanied by several lawyers. There he heard that a peasant had been maltreated in a nearby village. Gandhi decided to go and see him but he was interrupted by the police superintendent’s messenger who ordered him to return. Gandhi agreed but the messenger who drove him home served him with an official notice to quit Champaran immediately. Gandhi signed a receipt for the notice and wrote on it that he would disobey the order.

Question 4.
Why did the officials feel powerless without Gandhi’s cooperation? How did they react?
Answer:
When Gandhi was summoned to appear in court, he telegraphed Rajendra Prasad to come with his influential friends. The town of Motihari was filled with peasants, who had come because they had heard that the Mahatma, who wanted to help them, was in trouble with the authorities. The demonstration, in thousands, was the first step toward their liberation from fear. The officials felt powerless without Gandhi’s cooperation.

He helped them regulate the crowd. He proved that their might could be challenged by Indians. The government was taken aback and wanted to consult their superiors. The prosecutor requested the judge to postpone the trial but Gandhi protested against the delay. He read a statement stating that he was guilty of flouting the law but he expressed no regret for helping the cause of the poor peasants. He also refused to furnish bail and was eventually released without bail.

Question 5.
Civil disobedience had triumphed for the first time in modem India. When was it?
Answer:
Gandhi received summons to appear in court when he defied the order to leave Motihari. By morning, the peasants demonstrated to lend Gandhi support. Their spontaneous demonstration in thousands, around the courthouse was the beginning of their liberation from fear of the British. The officials were powerless and had to seek Gandhi’s help to regulate the crowd.

Several prominent lawyers from Bihar came to confer with Gandhi about his impending sentence. Gandhi convinced them to lend their voice and support to the sharecropping cause. The lawyers promised to follow Gandhi into jail. Gandhi viewed the support of the countrymen as true victory. A few days later, the case against Gandhi was dropped. Civil disobedience triumphed for the first time in modem India.

Question 6.
Cultural and social backwardness of the people was Gandhi’s chief concern. Explain.
Answer:
Gandhi was never satisfied with only political or economic solutions. He wanted to rectify the cultural and social backwardness in Champaran. He appealed for teachers and social workers to serve at Champaran.
Mahadev Desai and Narhari Parikh, two of Gandhi’s disciples, and their wives, volunteered for the work.
Several other arrived from Bombay, Poona and other distant parts of the land. Devadas, Gandhi’s youngest son, and Kasturba arrived from the ashram. Primary schools were opened in six villages. Kasturba taught the ashram rules on personal cleanliness and community sanitation. Gandhi also worked towards improving the health conditions and arranged for a doctor to volunteer his services for six months. Three medicines were made available to the poor farmers—castor oil, quinine, and sulphur ointment.

Indigo Value Based Questions

Question 1.
Gandhi compromised on the material terms because the peasants had gained what no money could buy. Explain.
Answer:
Gandhi was summoned to the offices of Sir Edward Gait, the Lieutenant Governor, with whom he had four interviews and an official commission of inquiry was ordered into the indigo sharecroppers’ situation. The commission that had Gandhi as the sole representative of the peasants, gathered a lot of evidence against the big planters, and they agreed to offer refunds to the peasants. The peasants expected repayment of the money in full but Gandhi asked for only fifty per cent. When the representative of the planters offered to refund twenty-five per cent, Gandhi agreed.

Gandhi realized that the monetary benefit that he achieved for the peasants in the way of the settlement was of less significance in comparison to the spirit of liberation they had gained. He explained that the amount of the refund was less important than the fact that the landlords had been forced to surrender a part of their money and bow down to law, bridging the divide between the landowners and the poor peasants.The peasants were made aware of their rights, their plights received a voice and they were consequently . liberated from their fear of the British.

Question 2.
“Self-reliance, Indian independence and help to sharecroppers were all bound together.” Justify.
Answer:
In Champaran, the landlords forced the peasants to enter into an arrangement to relieve them of the fifteen per cent sharecropping arrangement in return for compensation. The poor peasants were duped out of their money and they were demanding a refund. They appealed to Gandhi to fight for their cause. He resisted and was produced in a court in Motihari. Peasants flocked from around the area, and turned up in thousands to offer Gandhi their support. This planted the seeds of the first civil disobedience movement in India. Gandhi finally succeeded in making the British authorities order for reimbursement to the sharecroppers.

Though the peasants were compensated in part, they won against the system of landlord and the British government. It taught them an essential lesson in self-reliance and instilled them with courage to stand against injustice and British rule. The civil disobedience movement was the first of its kind in India, and paved way for the struggle to achieve Indian independence.

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Gymnosperms Various Types and its General Characteristics

Naked Seed Producing Plants

Michael Crichton’s Science Fiction is a book transformed into a Film of Steven Spielberg (1993) called Jurassic Park. In this film you might have noticed insects embedded in a transparent substance called amber which preserves the extinct forms. What is amber? Which group of plants produces Amber?

Amber is a plant secretion which is an efficient preservative that doesn’t get degraded and hence can preserve remains of extinct life forms. The amber is produced by Pinites succinifera, a Gymnosperm. In this chapter we shall discuss in detail about one group of seed producing plants called Gymnosperms.

Gymnosperms (Gr. Gymnos = naked; sperma = seed) are naked seed producing plants. They were dominant in the Jurassic and Cretaceous periods of Mesozoic era. The members are distributed throughout the temperate and tropical region of the world.

General Characteristic Features

1. Most of the gymnosperms are evergreen, woody trees or shrubs. Some are lianas (Gnetum)
2. The plant body is sporophyte and is differentiated into root, stem and leaves.
3. A well developed tap root system is present. Coralloid roots of Cycas have symbiotic association with blue green algae. In Pinus the roots have mycorrhizae.
4. The stem is aerial, erect and branched or unbranched (Cycas) with leaf scars.
5. In conifers two types of branches namely branches of limited growth (Dwarf shoot) and Branches of unlimited growth (Long shoot) is present.
6. Leaves are dimorphic, foliage and scale leaves are present. Foliage leaves are green, photosynthetic and borne on branches of limited growth. They show xerophytic features.
7. The xylem consists of tracheids but in Gnetum and Ephedra vessels are present.
8. Secondary growth is present. The wood may be Manoxylic (Porous, soft, more parenchyma with wide medullary ray – Cycas) or Pycnoxylic (compact with narrow medullary ray-Pinus).
9. They are heterosporous. The plant may be monoecious (Pinus) or dioecious (Cycas).
10. Microsporangia and megasporangia are produced on microsporophyll and megasporophyll respectively.
11. Male and female cones are produced.
12. Anemophilous pollination is present.
13. Fertilization is siphonogamous and pollen tube helps in the transfer of male nuclei.
14. Polyembryony (presence of many embryo) is present. The naked ovule develops into seed. The endosperm is haploid and develop before fertilization.
15. The life cycle shows alternation of generation. The sporophytic phase is dominant and gametophytic phase is highly reduced.
16. The photograph of some of the gymnosperms is given in Figure 2.8. Sporne (1965) classified gymnosperms into 3 classes, 9 orders and 31 families.

The Classes Include:-

• Cycadospsida
• Coniferopsida
• Gnetopsida.

Comparison of Gymnosperm with Angiosperms

Gymnosperms resemble with angiosperms in the following features:-

• Presence of well organised plant body which is differentiated into roots, stem and leaves.
• Presence of cambium in gymnosperms as in dicotyledons.
• Flowers in Gnetum resemble the male flower of the angiosperm. The zygote represent the first cell of sporophyte.
• Presence of integument around the ovule.
• Both plant groups produce seeds.
• Pollen tube helps in the transfer of male nucleus in both.
• Presence of eustele.

The difference between Gymnosperms and Angiosperms were given in Table 2.4.

Economic Importance Of Gymnosperms

Palaeobotany in India

The National wood fossil park is situated in Tiruvakkarai, a Village of Villupuram district of Tamil Nadu. The park contains petrified wood fossils approximately 20 million years old. The term ‘form genera’ is used to name the fossil plants because the whole plant is not recovered as fossils instead organs or parts of the extinct plants are obtained in fragments. Shiwalik fossil park-Himachal Pradesh, Mandla Fossil park-Madhya Pradesh, Rajmahal Hills-Jharkhand, Ariyalur – Tamilnadu are some of the fossil rich sites of India.

Some of the Fossil Representatives of Different Plant Groups are Given Below:

• Fossil Algae – Palaeoporella, Dimorphosiphon
• Fossil Bryophytes – Naiadita, Hepaticites, Muscites
• Fossil Pteridophytes – Cooksonia, Rhynia, Baragwanthia, Calamites
• Fossil Gymnosperms – Medullosa, Lepidocarpon, Williamsonia, Lepidodendron
• Fossil Angiosperms – Archaeanthus, Furcula

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Fungi Definition – Types, Characteristics, Classification and its Types

World War II and Penicillin
History Speaks on Fungi

Sir Alexander Fleming

Discovery of Penicillin in the year 1928 is a serendipity in the world of medicine. The History of World War II recorded the use of Penicillin in the form of yellow powder to save lives of soldiers. For this discovery – The wonderful antibiotic he shared Nobel Prize in Medicine in the year 1945 along with Ernest Boris chain and Sir Howard Walter Florey.

Milestones in Mycology

1729 – P.A. Micheli conducted spore culture experiments
1767 – Fontana proved that Fungi could cause disease in plants
1873 – C.H. Blackley proved fungi could cause allergy in Human beings
1904 – A.F.Blakeslee reported heterothallism in fungi
1952 – Pontecorvo and Roper reported Parasexual cycle

The word ‘fungus’ is derived from Latin meaning ‘mushroom’. Fungi are ubiquitous, eukaryotic, achlorophyllous heterotrophic organisms. They exist in unicellular or multicellular forms. The study of fungi is called mycology. (Gr. mykes – mushroom: logos – study). P.A. Micheli is considered as founder of Mycology. Few renowned mycologists include Arthur H.R. Buller, John Webster, D.L.Hawksworth, G.C.Ainsworth, B.B.Mundkur, K.C.Mehta, C.V. Subramanian and T.S. Sadasivan.

General Characteristic Features

Majority of fungi are made up of thin, filamentous branched structures called hyphae. A number of hyphae get interwoven to form mycelium. The cell wall of fungi is made up of a polysaccharide called chitin (polymer of N-acetyl glucosamine) and fungal cellulose.

The fungal mycelium is categorised into two types based on the presence or absence of septa (Figure 1.18). In lower fungi the hypha is aseptate, multinucleate and is known as coenocytic mycelium (Example: Albugo). In higher fungi a septum is present between the cells of the hyphae. Example: Fusarium.

The mycelium is organised into loosely or compactly interwoven fungal tissues called plectenchyma. It is further divided into two types prosenchyma and pseudoparenchyma. In the former type the hyphae are arranged loosely but parallel to one another. In the latter hyphae are compactly arranged and loose their identity.

In holocarpic forms the entire thallus is converted into reproductive structure whereas in Eucarpic some regions of the thallus are involved in the reproduction other regions remain vegetative. Fungi reproduce both by asexual and sexual methods. The asexual phase is called Anamorph and the sexual phase is called Teleomorph. Fungi having both phases are called Holomorph.

General sexual reproduction in fungi includes three steps:-

• Fusion of two protoplasts (plasmogamy)
• Fusion of nuclei (karyogamy) and
• Production of haploid spores through meiosis. Methods of reproduction in fungi is given in Figure 1.19.

Methods of Reproduction in Fungi

Asexual Reproduction

1. Zoospores:
They are flagellate structures produced in zoosporangia (Example: Chytrids).

2. Conidia:
The spores produced on condiophores (Example: Aspergillus, Penicillium).

3. Oidia/Thallospores/Arthrospores:
The hypha divided and developed in to spores called oidia (Example: Erysiphe).

4. Fission:
The vegetative cell divides into 2 daughter cells. (Example: Schizosaccharomyces-yeast).

5. Budding:
A small outgrowth is developed on parent cell, which gets detached and becomes independent. (Example: Saccharomycesyeast)

6. Chlamydospore:
Thick walled resting spores are called chlamydospores (Example: Fusarium).

Sexual Reproduction

1. Planogametic Copulation:

Fusion of motile gamete is called planogametic copulation.

a. Isogamy:
Fusion of morphologically and physiologicall similar gametes. (Example: Synchytrium).

b. Anisogamy:
Fusion of morphologically or physiologically dissimilar gametes (Example: Allomyces).

c. Oogamy:
Fusion of both morphologically and physiologically dissimilar gametes. (Example: Monoblepharis).

2. Gametangial Contact:

During sexual reproduction a contact is established between antheridium and Oogonium (Example: Albugo).

3. Gametangial Copulation:

Fusion of gametangia to form zygospore (Example: Mucor, Rhizopus).

4. Spermatization:

In this method a uninucleate pycniospore/microconidium is transferred to receptive hyphal cell (Example: Puccinia, Neurospora)

5. Somatogamy:

Fusion of two somatic cells of the hyphae (Example: Agaricus)

Classification of Fungi

Many mycologists have attempted to classify fungi based on vegetative and reproductive characters. Traditional classifications categorise fungi into 4 classes – Phycomycetes, Ascomycetes, Basidiomycetes and Deuteromycetes. Among these ‘Phycomycetes’ include fungal species of Oomycetes, Chytridiomycetes and Zygomycetes which are considered as lower fungi indicating algal origin of fungi.

Constantine J. Alexopoulos and Charles W. Mims in the year 1979 proposed the classification of fungi in the book entitled ‘Introductory Mycology’. They classified fungi into three divisions namely Gymnomycota, Mastigomycota and Amastigomycota. There are 8 subdivisions, 11 classes, 1 form class and 3 form subclasses in the classification proposed by them.

The salient features of some of the classes – Oomycetes, Zygomycetes, Ascomycetes, Basidiomycetes and Form class Deuteromycetes are discussed below.

Oomycetes

Coenocytic mycelium is present. The cell wall is made up of Glucan and Cellulose. Zoospore with one whiplash and one tinsel flagellum is present. Sexual reproduction is oogamous. Example: Albugo.

Zygomycetes

• Most of the species are saprophytic and live on decaying plant and animal matter in the soil. Some lead parasitic life (Example: Entomophthora on housefly).
• Bread mold fungi (Example: Mucor, Rhizopus) and coprophilous fungi (Fungi growing on dung Example: Pilobolus) belong to this group (Figure 1.20).
  
• The mycelium is branched and coenocytic.
• Asexual reproduction by means of spores produced in sporangia.
• Sexual reproduction is by the fusion of the gametangia which results in thick walled zygospore. It remains dormant for long periods.
• The zygospore undergoes meiosis and produce spores.

Ascomycetes

1. Ascomycetes include a wide range of fungi such as yeasts, powdery mildews, cup fungi, morels and so on (Figure 1.21).
2. Although majority of the species live in terrestrial environment, some live in aquatic environments both fresh water and marine.
3. The mycelium is well developed, branched with simple septum.
4. Majority of them are saprophytes but few parasites are also known (Powdery mildew – Erysiphe).
5. Asexual reproduction takes place by fission, budding, oidia, conidia, and chlamydospore.
6. Sexual reproduction takes place by the fusion of two compatible nuclei.
7. Plasmogamy is not immediately followed by karyogamy, instead a dikaryotic condition is prolonged for several generations.
8. A special hyphae called ascogenous hyphae is formed.
9. A crozier is formed when the tip of the ascogenous hyphae recurves forming a hooked cell. The two nuclei in the penultimate cell of the hypha fuse to form a diploid nucleus. This cell forms young ascus.
10. The diploid nucleus undergo meiotic division to produce four haploid nuclei, which further divide mitotically to form eight nuclei. The nucleus gets organised into 8 ascospores.
11. The ascospores are found inside a bag like structure called ascus. Due to the presence of ascus, this group is popularly called “Sac fungi”.
12. Asci gets surrounded by sterile hyphae forming fruit body called ascocarp.
13. There are 4 types of ascocarps namely Cleistothecium (Completely closed), Perithecium (Flask shaped with ostiole), Apothecium (Cup shaped, open type) and Pseudothecium.

Basidiomycetes

Basidiomycetes include puff balls, toad stools, Bird’s nest fungi, Bracket fungi, stink horns, rusts and smuts (Figure 1.22).

• The members are terrestrial and lead a saprophytic and parasitic mode of life.
• The mycelium is well developed, septate with dolipore septum (bracket like). Three types of mycelium namely primary (Monokaryotic), secondary (Dikaryotic) and tertiary are found.
• Clamp connections are formed to maintain dikaryotic condition.
• Asexual reproduction is by means of conidia, oidia or budding.
• Sexual reproduction is present but sex organs are absent. Somatogamy or spermatisation results in plasmogamy.
• Karyogamy is delayed and dikaryotic phase is prolonged.
• Karyogamy takes place in basidium and it is immediately followed by meiotic division.
• The four nuclei thus formed are transformed into basidiospores which are borne on sterigmata outside the basidium (Exogenouz).
• The basidium is club shaped with four basidiospores, thus this group of fungi is popularly called “Club fungi”. The fruit body formed is called Basidiocarp.

Deuteromycetes or Fungi Imperfecti

The fungi belonging to this group lack sexual reproduction and are called imperfect fungi. A large number of species live as saprophytes in soil and many are plant and animal parasites. Asexual reproduction takes place by the production of conidia, chlamydospores, budding, oidia etc., Conidia are also produced in special structures called pycnidium, acervulus, sporodochium and synnemata (Figure 1.23). Parasexual cycle operates in this group of fungi. This brings genetic variation among the species.

Economic Importance

Fungi provide delicious and nutritious food called mushrooms. They recycle the minerals by decomposing the litter thus adding fertility to the soil. Dairy industry is based on a single celled fungus called yeast. They deteriorate the timber. Fungi cause food poisoning due the production of toxins. The Beneficial and harmful activities of fungi are discussed below:

Beneficial Activities

Food

Mushrooms like Lentinus edodes, Agaricus bisporus, Volvariella volvaceae are consumed for their high nutritive value. Yeasts provide vitamin B and Eremothecium ashbyii is a rich source of Vitamin B₁₂.

Medicine

Fungi produce antibiotics which arrest the growth or destroy the bacteria. Some of the antibiotics produced by fungi include Penicillin (Penicillium notatum) Cephalosporins (Acremonium chrysogenum) Griseofulvin (Penicillium griseofulvum). Ergot alkaloids (Ergotamine) produced by Claviceps purpurea is used as vasoconstrictors.

Industries

Production of Organic Acid:

For the commercial production of organic acids fungi are employed in the Industries. Some of the organic acids and fungi which help in the production of organic acids are: citric acid and gluconic acid – Aspergillus niger, Itaconic acid – Aspergillus terreus, Kojic acid – Aspergillus oryzae.

Bakery and Brewery

Yeast(Saccharomyces cerevisiae) is used for fermentation of sugars to yield alcohol. Bakeries utilize yeast for the production of Bakery products like Bread, buns, rolls etc., Penicillium roquefortii and Penicillium camemberti were employed in cheese production.

Production of Enzymes

Aspergillus oryzae, Aspergillus niger were employed in the production of enzymes like amylase, protease, lactase etc. Rennet which helps in the coagulation of milk in cheese manufacturing is derived from Mucor spp.

Agriculture

Mycorrhiza forming fungi like Rhizoctonia, Phallus, Scleroderma helps in absorption of water and minerals. Fungi like Beauveria bassiana, Metarhizium anisopliae are used as Biopesticides to eradicate the pests of crops. Gibberellin, produced by a fungus Gibberella fujikuroi induce the plant growth and is used as growth promoter.

Harmful Activities

Fungi like Amanita phalloides, Amanita verna, Boletus satanus are highly poisonous due to the production of Toxins. These fungi are commonly referred as “Toad stools”.

Aspergillus, Rhizopus, Mucor and Penicilium are involved in spoilage of food materials. Aspergillus flavus infest dried foods and produce carcinogenic toxin called aflatoxin.

Patulin, ochratoxin A are some of the toxins produced by fungi.Fungi cause diseases in Human beings and plants (Table 1.11).

Activity 1.4

Get a button mushroom. Draw diagram of the fruit body. Take a thin longitudinal section passing through the gill and observe the section under a microscope. Record your observations.

Activity 1.5

Keep a slice of bread in a clean plastic tray or plate. Wet the surface with little water. Leave the setup for 3 or 4 days. Observe the mouldy growth on the surface of the bread. Using a needle remove some mycelium and place it on a slide and stain the mycelium using lactophenol cotton blue. Observe the mycelium and sporangium under the microscope and record your observation and identify the fungi and its group based on characteristic features.

Mycorrhizae

The symbiotic association between fungal mycelium and roots of plants is called as mycorrhizae. In this relationship fungi absorb nutrition from the root and in turn the hyphal network of mycorrhizae forming fungi helps the plant to absorb water and mineral nutrients from the soil (Figure 1.24). Mycorrhizae is classified into three types (Table 1.12)

Importance of 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

Lichens

The symbiotic association between algae and fungi is called lichens. The algal partner is called Phycobiont or Photobiont., and the fungal partner is called Mycobiont. Algae provide nutrition for fungal partner in turn fungi provide protection and also help to fix the thallus to the substratum through rhizinae.

Asexual reproduction takes place through fragmentation, Soredia and Isidia. Phycobionts reproduce by akinetes, hormogonia, aplanospore etc., Mycobionts undergo sexual reproduction and produce ascocarps.

Classification

• Based on the habitat lichens are classified into following types: Corticolous (on Bark) Lignicolous (on Wood) Saxicolous (on rocks) Terricolous (on ground) Marine (on siliceous rocks of sea) Fresh water (on siliceous rock of fresh water).
• On the basis of morphology of the thallus they are divided into Leprose (a distinct fungal layer is absent) Crustose-crust like; Foliose-leaf like; Fruticose- branched pendulous shrub like (Figure 1.25).
  
• The distribution of algal cells distinguishes lichens into two forms namely Homoiomerous (Algal cells evenly distributed in the thallus) and Heteromerous (a distinct layer of algae and fungi present).
• If the fungal partner of lichen belongs to ascomycetes, it is called Ascolichen and if it is basidiomycetes it is called Basidiolichen.

Lichens secrete organic acids like Oxalic acids which corrodes the rock surface and helps in weathering of rocks, thus acting as pioneers in Xerosere. Usnic acid produced from lichens show antibiotic properties. Lichens are sensitive to air pollutants especially to sulphur-di-oxide. Therefore, they are considered as pollution indicators.

The dye present in litmus paper used as acid base indicator in the laboratories is obtained from Roccella montagnei. Cladonia rangiferina (Reindeer mose) is used as food for animals living in Tundra regions.

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Exchange of Gases in Respiratory Pigments, Methaemoglobin

The primary site for the exchange of gases is the alveoli. The uptake of O₂ and the release of CO₂ occur between the blood and tissues by simple diffusion driven by partial pressure gradient of O₂ and CO₂. Partial pressure is the pressure contributed by an individual gas in a mixture of gases.

It is represented as pO₂ for oxygen and pCO₂ for carbon-dioxide. Due to pressure gradients, O₂ from the alveoli enters into the blood and reaches the tissues. CO₂ enters into the blood from the tissues and reaches alveoli for elimination. As the solubility of CO₂ is 20-25 times higher than that of O₂, the partial pressure of CO₂ is much higher than that of O₂ (Table 6.1 and Figure 6.6).

Respiratory Pigments

Haemoglobin

Haemoglobin belongs to the class of conjugated protein. The iron containing pigment portion haem constitutes only 4% and the rest colourless protein globin belongs to histone classs. Haemoglobin has a molecular weight of 68,000 daltons and contains four atoms of iron, each of which can combine with a molecule of oxygen.

Methaemoglobin

If the iron component of the haem moieties is in the ferric state, than the normal ferrous state, it is called methaemoglobin. Methaemoglobin does not bind O₂. Normally RBC contains less than 1% methaemoglobin.


Table 6.1 Partial pressure of Oxygen and Carbon dioxide (in mmHg) in comparison to those gases in the atmosphere.

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Respiratory Organs in Various Organisms

Different animals have different organs for exchange of gases, depending upon their habitats and levels of organization. The amount of dissolved oxygen is very low in water compared to the amount of oxygen in the air. So the rate of breathing in aquatic organisms is much faster than land animals.

In animals like sponges, coelenterates and flatworms exchange of gases takes place through the body surface by simple diffusion. Earthworms use their moist skin, whereas insects have tracheal tubes. Gills are used as respiratory organs in most of the aquatic Arthropods and Molluscs.

Among vertebrates, fishes use gills whereas amphibians, reptiles, birds and mammals have well vascularised lungs. Frogs spend most of their time in water and also use their moist skin for respiration along with lungs and bucco pharynx.

Human Respiratory System

The respiratory system includes external nostrils, nasal cavity, pharynx, larynx, trachea, bronchi and bronchioles and lungs which contain alveoli (Figure 6.1). The parts starting from the external nostrils up to the terminal bronchioles constitute the conducting zone, whereas the alveoli and the ducts are called the respiratory zone. The parts of the conducting zone, humidifies and warms the incoming air.

In human beings, air enters the upper respiratory tract through the external nostrils. The air passing through the nostrils is filtered by fine hairs and mucus lining the passage. The external nostrils lead to the nasal chamber which opens into the nasopharynx which opens through the glottis of the larynx region into the trachea. The ciliated epithelial cells lining the trachea, bronchi and bronchioles secrete mucus.

Mucus membrane lining the airway contains goblet cells which secrete mucus, a slimy material rich in glycoprotein. Microorganisms and dust particles attach in the mucus films and are carried upwards to pass down the gullet during normal swallowing. During swallowing a thin elastic flap called epiglottis prevents the food from entering into the larynx and avoids choking of food.

The trachea is semiflexible tube supported by multiple cartilaginous rings which extends up to the midthoracic cavity and at the level of the 5^th thoracic vertebra where it divides into right and left primary bronchi, one bronchus to each lung. Within the lungs the bronchi divides repeatedly into secondary and tertiary bronchi and further divides into terminal bronchioles and respiratory bronchioles.

Bronchi have ‘C’ shaped curved cartilage plates to ensure that the air passage does not collapse or burst as the air pressure changes during breathing. The bronchioles are without cartilaginous rings and have rigidity that prevent them from collapsing but are surrounded by smooth muscle which contracts or relaxes to adjust the diameter of these airways.

The fine respiratory bronchioles terminate into highly vascularised thin walled pouch like air sacs called alveoli meant for gaseous exchange (Figure 6.2, 6.3). The diffusion membrane of alveolus is made up of three layers – the thin squamous epithelial cells of the alveoli, the endothelium of the alveolar capillaries and the basement substance found in between them. The thin squamous epithelial cells of the alveoli are composed of Type I and Type II cells. Type I cells are very thin so that gases can diffuse rapidly through them. Type II cells are thicker, synthesize and secrete a substance called Surfactant.

The lungs are light spongy tissues enclosed in the thoracic cavity surrounded by an airtight space. The thoracic cavity is bound dorsally by the vertebral column and ventrally by the sternum, laterally by the ribs and on the lower side by the dome shaped diaphragm.

The lungs are covered by double walled pleural membrane containing a several layers of elastic connective tissues and capillaries, which encloses the pleural fluid. Pleural fluid reduces friction when the lungs expand and contract.

Characteristic Features of Respiratory Surface:

• Surface area must be very large and richly supplied with blood vessels
• Should be extremely thin and kept moist
• Should be in direct contact with the environment
• Should be permeable to respiratory gases

The Steps Involved in Respiration are:-

• The exchange of air between the atmosphere and the lungs.
• The exchange of O₂ and CO₂ between the lungs and the blood.
• Transport of O₂ and CO₂ by the blood.
• Exchange of gases between the blood and the cells.
• Uptake of O₂ by the cells for various activities and the release of CO₂.

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Timber Defintion and Its Various Types

The basic need of shelter is obtained from the timber trees.

Teak

Botanical name: Tectona grandis
Family: Lamiaceae

Origin and Area of cultivation:

This is native to South east Asia. It is observed wild in Assam. But cultivated in Bengal, Assam, Kerala, Tamil Nadu and North-West India.

Uses

It is one of best timbers of the world. The heartwood is golden yellow to golden brown when freshly sawn, turning darker when exposed to light. Known for its durability as it is immune to the attack of termites and fungi.

The wood does not split or crack and is a carpenter friendly wood. It was the chief railway carriage and wagon wood in India. Ship building and bridge-building depends on teakwood. It is also used in making boats, toys, plywood, door frames and doors.