Periodic Subject Lesson: A Science Self-Study

Lesson Overview

• Understanding Nutrients and Their Functions
• Balanced Diet and Deficiency Diseases
• Food Testing – Carbohydrates
• Plant Parts and Their Functions
• Types of Animals Based on Food Habits
• Sprouting and Germination
• Vitamins – The Disease Fighters
• Bees and the Process of Making Honey
• Concepts Covered and Critical Thinking Prompts

Science helps us explore the mysteries of the natural world. From understanding what's inside our food to discovering how plants grow and animals survive, science is part of our daily lives. This lesson is designed for offering deep understanding of essential science topics that appear in school assessments and quizzes.

Understanding Nutrients and Their Functions

In this lesson, we will explore the building blocks of our body (nutrients), food classification, plant structures, disease prevention, and fascinating processes like honey-making and seed germination.

• Identifying nutrients like proteins, vitamins, carbohydrates
• Understanding plant parts (e.g., potato as a stem)
• Testing food for carbohydrates using iodine
• Classifying animals by diet (herbivore, omnivore, etc.)
• Recognizing the role of bees in honey production
• Linking diseases to nutrient deficiencies
• Observing plant growth through sprouting

What are Nutrients?

Nutrients are substances in food that our body needs to grow, stay healthy, and function properly. The major types of nutrients are:

Critical Thinking:

• Why do we feel tired if we don't eat carbohydrates? Carbohydrates are our main energy source. Without them, our body cannot function actively.
  
• Why is protein known as the ‘body-building nutrient'? Because it repairs cells and helps in growth, especially during childhood when our body is developing.

Take This Quiz:

Class-Vll Periodic Test-1 Subject-Science

Balanced Diet and Deficiency Diseases

What is a Balanced Diet?

A balanced diet contains all the necessary nutrients in the right amounts. It ensures good health and growth.

Unbalanced diets lead to deficiency diseases.

Examples of Deficiency Diseases:

Question for Reflection: What might happen if someone eats only fast food every day?

Food Testing – Carbohydrates

How Do We Test for Carbohydrates?

We use iodine solution to test for the presence of starch, which is a type of carbohydrate.

• When iodine is added to a food item like boiled potato or rice and it turns blue-black, starch is present.
  
• If there is no color change, starch is not present.
  

Scientific Reasoning: Starch molecules react with iodine molecules to form a compound that gives the blue-black color.

Plant Parts and Their Functions

Plants have different parts that perform specific roles:

Deep Dive: What is a Potato?

Though potatoes grow underground, they are not roots but stems. A potato is a tuber, a swollen underground stem that stores food for the plant. It has "eyes" from which new plants can grow.

Misconception Alert: Many think potatoes are roots because they grow in soil, but observing their structure and function shows otherwise.

Types of Animals Based on Food Habits

Animals are classified by what they eat:

Scientific Context: Deer are classified as herbivores because they only eat plant-based foods like grass and leaves. Bears are omnivores because they eat both plants and meat.

Sprouting and Germination

When seeds like moong or chana are soaked in water for a day or two, a small white structure begins to emerge. This is called a sprout.

What is Sprouting?

Sprouting is the early stage of seed germination, where the seed starts to grow into a plant.

Nutritional Fact: Sprouts are rich in vitamins and are very healthy to eat.

Process of Sprouting:

1. Soak seeds in water for 6–12 hours.
   
2. Drain and keep them in a moist cloth for 1–2 days.
   
3. Tiny shoots will emerge.

Why does this happen? Water activates enzymes in the seed that begin breaking down stored food into energy for growth.

Vitamins – The Disease Fighters

Vitamins are protective nutrients.

• Vitamin A: Good for eyes and skin.
  
• Vitamin C: Helps heal wounds, fights infections.
  
• Vitamin D: Strengthens bones.
  
• Vitamin E: Helps skin and muscles.
  
• Vitamin B Complex: Helps digestion and nerve function.
  

Food Sources:

Bees and the Process of Making Honey

Bees are insects that play a key role in pollination and honey production.

How Do Bees Make Honey?

1. Bees collect nectar from flowers.
   
2. Nectar is stored in their special honey stomach.
   
3. Inside the bee's body, enzymes break down nectar into simpler sugars.
   
4. Back in the hive, nectar is regurgitated and processed by other bees.
   
5. Bees fan it with their wings to remove moisture, turning it into thick honey.
   
6. Honey is stored in honeycombs.
   

Scientific Interest: This process shows cooperation in nature and the role of insects in food chains.

Concepts Covered and Critical Thinking Prompts

Test Yourself:

• Why is it important to eat a variety of foods each day?
  
• Can a person stay healthy by eating only one type of nutrient?
  
• What clues help us identify different plant parts?
  
• How can we relate animal eating habits to their physical features?

Take This Quiz:

Class-Vl Periodic test-1 Subject-Science