Science in Everyday Life

Unit 4

Science in Everyday Life

Learning Objectives

After learning this lesson, students will be able to

• know the nutritional value of milk

• explore the benefits of cooking

• learn about baking of bread, biscuit and cake

• know about gadgets used in daily life

Let us Recall

Teacher : What do you have as soon as you get up?

Students : Tea, coffee and milk .

Teacher : Good. What do they contain?

Ram : Milk, tea dust, coffee powder and sugar.

Teacher : Very good. Do you know why we drink milk in the morning?

Ram : Yes. It is good for our health.

Teacher : Correct, let us learn more about milk in this lesson.

I. Milk

Milk is produced by some animals for nourishing their young ones. Milk from many animals is used by humans. Cow‛s milk is used commonly.

1. Sources of Milk

Milk is primarily obtained from mammals. They are obtained from other sources too. Examples: Soya milk, nut and seed based milk.

Based on the amount of fat present in the milk, it can be classified as Whole milk, Low fat milk and Fat free milk.

Do you Know: People all over the world get their milk from mammals like sheep, goat, camel, donkey, horse, yak, water buffalo, reindeer and even moose.

2. Nutritional value of Milk

Milk contains water, sugar, protein, fat, vitamins and minerals.

Sugar : Milk has sweet taste because it has a special sugar called lactose.

Protein : It helps to build muscles.

Fat : Fat present in the milk is called butter. Butter is more delicious than any other fat.

Vitamins : Vitamin-D in milk helps to maintain the bones.

Minerals : Calcium is a mineral. It helps to build healthy bones and teeth.

Milk in daily life

• Primary food for babies.

• Gives curd, butter, butter milk and ghee.

• Health drink for adults and sick people.

• Used for making cheese, paneer and milk sweets

• Used in Ice cream and Chocolates.

• Used during festivals and ceremonies.

3. Health Benefits of milk

1. It strengthens bones and teeth.

2. It maintains blood pressure.

3. It reduces the risk of heart disease.

4. It is a source of energy.

Try to Answer

1. Milk is a rich source of Calcium. (Calcium / Iron)

2. Milk contains sugar, protein and fat.

II. Food materials

What is food? Food is one of the basic needs of our life. Food provides energy. It is usually made by cooking plants or animals. It contains essential nutrients to keep our body healthy.

Needs of food

• Gives energy

• Promotes growth

 • Improves immunity

 • Helps our body repair itself

Food can be classified into two types:

1. Raw Food - Raw food is the food that does not have to be cooked to eat. Examples: Fruits, carrot, ground nut seeds.

2. Cooked food - Cooked food is the food that has been cooked to eat. Examples: Rice, vegetable curry, bread.

Let us Do

Simple tasks such as pouring liquid into the bowl, sprinkling pepper on the of the omelet or dosa, peeling off onions, powdering coriander seeds can be done by you. Always help the elders in the kitchen.

1. Cooking

Do you know how many food items are their that you will not be able to eat without cooking? Cooking is important. It makes food suitable for consumption.

Methods of Cooking

Boiling, Steaming, Frying, Deep frying, Roasting, Grilling

Benefits of Cooking

Cooking causes many useful changes in food.

1. It makes nutrients ready for digestion.

2. It helps to make food in the desired texture, flavour and taste.

3. It destroys harmful microbes.

Try to Answer

1. Fruits and carrots are examples of raw food.

2. Rice and bread are examples of cooked food.

Let us discuss

Look at the things shown in the picture and discuss their uses with your friends.

III. Baking of Bread, Biscuit and Cake

Baking is a method of cooking. We use dry heat to bake. Bread, biscuit and cake are some examples of baked food items.

1. Bread

Bread is a common food product prepared from dough by baking. It is an important source of energy for sick people. It is also one of the ancient foods made by humans. Bread is a low fat food.

Bread has the nutrients required for normal development and good health.

To make bread we need wheat flour, yeast, water, sugar and salt.

Do you know? Bread spoils six times faster when kept in fridge than at room temperature.

2. Biscuit

Biscuit is a small, flour – based baked food. They are generally made of wheat flour or oats and sweetened with sugar.

The main ingredients of biscuit are flour, sugar, butter, water, milk, baking powder and flavours.

Biscuits are salty or sweet. Some biscuits have cream in between.

Do you know? Biscuits are made with baking powder to make it airy.

3. Cake

Cake is a baked dessert. It is like a sweet bread. There are many varieties of cake with specific ingredients. We cake during celebrations .

The common ingredients of the cake are flour, sugar, eggs, oil, baking powder and flavouring agent.

Try to Answer

1. Bread is low (low / high) fat food.

2. Biscuits are made from wheat flow ( wheat flour / rice flour).

3. Cake is associated with birthday celebrations (cake / biscuit).

Activity

Visit a bakery near you and learn about baking of bread, biscuit and cakes.

IV. Gadgets

Think of the electronic devices we use everyday.

The phone that we use, the camera that goes with us on every vacation, the TV that we watch for fun all these devices that we use are called gadgets.

A gadget is a small electronic machine or device which does something useful. Number of gadgets have changed our lives. They make our life enjoyable.

Examples: Laptop

Phone

Camera

Pen drive

Speaker

Smart Phones

Apart from communication, smart phones have the ability to access the internet and store files, take photos, track location and much more.

Portable Music Player

It stores and plays thousands of songs.

We can listen to songs anywhere, anytime.

Tablets

People use tablets to read books, play games and watch videos.

Pen Drive

It is a small gadget used for storing and transferring any type of file in / from a computer.

Electric Torch

Portable hand-held electric light. Torch is used to provide light in the dark places when it is switched on.

Try to Answer

Write the names of the given gadgets.

(Web cam, Remote, Speaker, Camera, Headphone)