Subject Experts Solutions for Chapter: Micro-Organisms: Friend and Foe, Exercise 3: TOUGH NUT

Ramu noticed that milk turns into curd more quickly when left in the open than in a refrigerator. Can you explain why?

Renu saw in the news that a well-preserved body of a man was recently found in Antarctica. She wants to know how it survived the decaying process for so long. Can you explain the reason?

Why do you think sealed food packets are usually filled with nitrogen?

Reena recently fell sick and was advised by the doctor to always wash hands before eating anything and also after visiting the washroom. Why did the doctor give this advice?

Sarah likes to spend her free time in the park watching bird-lovers feeding pigeons. One day, as she was watching them, she noticed a family with an infant. The infant's father purchased apples, oranges, mangoes, and bananas from the roadside vendor. As there was no vendor available, both parents started eating the fruits without washing them. The mother mashed the fruits into small pieces in order to feed the infant. Sarah realised that she had read about something similar in chapter 2 of her science textbook. What did Sarah realise? It is advisable to eat fruits without washing?

Shanti lives in a slum area on the borders of a metro rail track. There has been a marked increase in dengue and malaria cases in the slum. Shanti is worried because ten cases of dengue and fifteen cases of malaria were reported during the last month. Today a team of representatives, from the department of health, has talked to slum dwellers. They also met Shanti and asked her about unhealthy conditions in the slum. The health department is of the view that stagnant water in the slum is the real cause of dengue and malaria. They have asked the people to clean the slum and to remove the stagnant water. Shanti was unable to understand this. Can you help Shanti to understand the relationship between stagnant water, dengue, and malaria?

Shanti lives in a slum area on the borders of a metro rail track. There has been a marked increase in dengue and malaria cases in the slum. Shanti is worried because ten cases of dengue and fifteen cases of malaria were reported during the last month. Today a team of representatives, from the department of health, has talked to slum dwellers. They also met Shanti and asked her about unhealthy conditions in the slum. The health department is of the view that stagnant water in the slum is the real cause of dengue and malaria. They have asked the people to clean the slum and to remove the stagnant water. Shanti was unable to understand this.

How can we, as students, help the slum dwellers?