Nutrition in Plants Full Chapter Class 7 Science | NCERT Science Class 7 Chapter 1

Introduction

This tutorial provides a comprehensive overview of the topic "Nutrition in Plants" as outlined in Class 7 Science, NCERT Chapter 1. Understanding how plants obtain and utilize nutrients is essential for grasping fundamental biological concepts. This guide will walk you through the key concepts, processes, and types of nutrition in plants.

Step 1: Understanding Plant Nutrition

Plant nutrition refers to the process by which plants obtain the necessary nutrients for growth and development. It primarily involves two types of nutrition:

• Autotrophic Nutrition: This is the process where plants produce their own food using sunlight, carbon dioxide, and water through photosynthesis.
• Heterotrophic Nutrition: This involves obtaining food from external sources, which is less common in plants but occurs in some species.

Step 2: Photosynthesis Process

Photosynthesis is crucial for autotrophic nutrition. Here’s how it works:

1. Sunlight Absorption: Plants absorb sunlight using chlorophyll, the green pigment present in leaves.
2. Carbon Dioxide Intake: Carbon dioxide enters the leaves through tiny openings called stomata.
3. Water Absorption: Roots absorb water from the soil.
4. Food Production:
   • The absorbed sunlight, carbon dioxide, and water are converted into glucose (a type of sugar) and oxygen.
   • The overall equation for photosynthesis is:

     6CO2 + 6H2O + sunlight → C6H12O6 + 6O2
     

5. Oxygen Release: Oxygen produced during photosynthesis is released into the atmosphere.

Step 3: Nutrient Types and Their Sources

Plants require various nutrients for growth, which can be categorized as:

• Macronutrients: These are needed in larger quantities and include:

  • Nitrogen (N)
  • Phosphorus (P)
  • Potassium (K)

• Micronutrients: These are needed in smaller amounts and include:

  • Iron (Fe)
  • Manganese (Mn)
  • Zinc (Zn)

Practical Tips

• Ensure soil has adequate nutrients for optimal plant health.
• Use fertilizers to supplement nutrient deficiencies.

Step 4: Factors Affecting Photosynthesis

Several factors influence the rate of photosynthesis, including:

1. Light Intensity: Higher light levels increase the rate of photosynthesis.
2. Carbon Dioxide Concentration: More CO2 can enhance food production.
3. Temperature: Every plant has an optimal temperature range for photosynthesis.

Common Pitfalls

• Overexposure to light can damage chlorophyll.
• Insufficient water can slow down the photosynthesis process.

Step 5: Special Types of Nutrition in Plants

Some plants exhibit unique nutritional modes, such as:

• Insectivorous Plants: These plants, like the Venus flytrap, trap insects to obtain nutrients.
• Parasitic Plants: These plants, such as dodder, derive nutrients from host plants.

Conclusion

Understanding nutrition in plants is vital for appreciating their role in ecosystems and agriculture. Remember the key processes of photosynthesis and the importance of both macronutrients and micronutrients. For further study, consider exploring the specific adaptations of unique plants in their nutrient acquisition strategies. This foundational knowledge will serve you well in future studies in biology and environmental science.