NCERT MCQ Solutions for Class 5 EVS Our Wondrous World Chapter 3 The Mystery of Food

Microbes are tiny living organisms found everywhere. Some spoil food by changing its taste, smell and appearance, while others help in making useful products like curd and idli batter.

Microbes are too small to be seen with the naked eye. A microscope magnifies them so we can observe their shape, structure and activity on different substances, including food.

Microbes require moisture, air and a suitable temperature to multiply. Removing any one of these conditions—like by drying, sealing, or cooling—slows down or stops their growth completely.

Drying removes moisture from food. Without water, microbes cannot survive, so chillies, papads and herbs remain unspoiled for longer periods when dried in sunlight or by other methods.

Oil creates a protective layer over the pickle that blocks air. Since microbes need air to grow, this method keeps pickles fresh and safe for a long time.

Freezing and refrigeration lower the temperature so much that microbes cannot grow quickly. This helps in storing perishable items like milk, butter and vegetables for a few days.

Black pepper was historically a highly valued spice in trade. Vasco da Gama travelled to India mainly to collect it, highlighting its importance in global history and economy.

Incisors are the sharp, flat teeth in the front of the mouth. They are designed for cutting and biting food into smaller pieces before it is chewed further.

Canines are pointed teeth found next to the incisors. They are used to tear food, especially meat or tough items, into smaller, chewable portions.

Certain bacteria, such as Lactobacillus, help ferment milk into curd. These good microbes aid digestion and improve gut health when consumed.

Canning stores food in airtight containers to keep out air and moisture, preventing microbial growth. This method allows food to stay fresh for months without refrigeration.

Disha’s father brought lychees during the rainy season. Seasonal fruits taste better, are fresher and contain more nutrients compared to those stored or transported for long periods.

Rinsing removes leftover food particles from the mouth, reducing the chances of bacterial growth, tooth decay and bad breath, thus maintaining good oral hygiene.

Neem leaves are used traditionally to keep stored grains safe from insects. Their smell and natural chemicals repel pests without harming the grains.

Eating spoiled food allows harmful microbes into the body, which can cause food poisoning, upset stomach, diarrhoea or vomiting, and may require medical attention in severe cases.

Aam papad is made by drying mango pulp in the sun until it loses moisture. This prevents microbial growth and preserves the fruit’s flavour for months.

Chewing breaks food into smaller pieces and mixes it with saliva, which contains enzymes that begin digestion. It also reduces the risk of choking while swallowing.

Salt and sugar absorb moisture from food, making it unsuitable for microbial growth. Pickles, jams and salted fish are examples of this preservation method.

Exposure to sunlight removes moisture from tomato slices, causing them to shrink and wrinkle. Without moisture, microbial growth slows down, thus preserving the tomatoes.

Saliva contains enzymes that break down carbohydrates into simpler forms right in the mouth. Chewing releases more saliva, aiding in easier and faster digestion later in the stomach.