The Invisible Living World

Rani reads that microorganisms are what set milk into curd. She says curd must then be dangerous to eat, since germs make people ill. Suresh says that is not true of every microorganism. Who is right?

Leftover vegetables went bad in two days. Lata says food spoils because air gets to it. Nikhil says air gets to biscuits in an open tin too, yet they last for months. What actually spoils the food?

Teena has a cold, with a runny nose and a cough. Her brother Rohit says take an antibiotic, it kills germs. Her sister Neha, who has read about this, says an antibiotic will do nothing for this. Who is right?

Pooja boils milk and leaves it covered on the table, saying it will not spoil now because boiling killed the germs. Irfan says it still has to go into the fridge. Who is right?

One slice of bread has a green patch. Geeta cuts off that corner and throws it away, saying the rest of the slice is fine to eat. Her brother Vivek says the whole slice should go. Who is right?

Two children drank from the same school tap. By evening one had a stomach upset and the other was fine. A teacher says this proves the tap water is safe. Can that conclusion be drawn?