Science Class 10 - Life Processes Notes

Life Processes

Welcome to the chapter on Life Processes for Class 10. In this chapter, you will learn about the basic processes that are essential for living organisms, such as nutrition, respiration, transportation, and excretion. By the end of this chapter, you will understand how living beings survive, grow, and maintain their bodies.

Introduction

All living organisms perform certain basic functions to maintain their life. These functions are called life processes. The main life processes are nutrition, respiration, transportation, and excretion.

Key Concepts

• Nutrition: The process by which living organisms obtain and use food.
• Respiration: The process of releasing energy from food.
• Transportation: The movement of substances like water, minerals, and food within the body.
• Excretion: The removal of waste products from the body.

Nutrition

Nutrition is the process of taking in food and using it for growth, energy, and repair. There are two main types:

• Autotrophic Nutrition: Organisms like plants make their own food by photosynthesis.
• Heterotrophic Nutrition: Organisms like animals and humans get food by eating plants or other animals.

Example: Green plants use sunlight, water, and carbon dioxide to make food.

Respiration

Respiration is the process by which living things get energy from food. It can be:

• Aerobic Respiration: Uses oxygen to break down food and release energy.
• Anaerobic Respiration: Does not use oxygen and produces less energy.

Example: Humans breathe in oxygen and breathe out carbon dioxide.

Transportation

Transportation is the movement of water, minerals, and food to all parts of the body.

• In Plants: Water and minerals are transported by xylem; food is transported by phloem.
• In Animals: Blood transports oxygen, food, and waste products throughout the body.

Excretion

Excretion is the process of removing waste products from the body.

• In Humans: Kidneys remove waste as urine.
• In Plants: Waste products are removed through leaves and other parts.

Other Life Processes

• Growth: Increase in size and number of cells.
• Reproduction: Producing new individuals.
• Movement: Change in position or place.
• Response to Stimuli: Reacting to changes in the environment.

Practice Questions

1. What is the difference between autotrophic and heterotrophic nutrition?
2. Name the organs involved in human excretion.
3. How do plants transport water and food?
4. What is aerobic respiration?
5. Why is transportation important in living organisms?

Challenge Yourself

• Draw and label the human digestive system.
• Explain the process of photosynthesis in your own words.

Did You Know?

• The human heart beats about 70 times per minute!
• Plants release oxygen during photosynthesis, which we need to breathe.

Glossary

• Photosynthesis: The process by which green plants make food using sunlight.
• Xylem: Plant tissue that carries water and minerals from roots to leaves.
• Phloem: Plant tissue that carries food from leaves to other parts.
• Kidneys: Organs that remove waste from the blood in humans.

Answers to Practice Questions

1. Autotrophic nutrition: Organisms make their own food (e.g., plants). Heterotrophic nutrition: Organisms get food by eating other living things (e.g., animals).
2. Kidneys, lungs, and skin.
3. Water and minerals are transported by xylem; food is transported by phloem.
4. Aerobic respiration is the process of breaking down food using oxygen to release energy.
5. Transportation moves important substances to all parts of the body and removes waste.

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Understanding life processes helps us know how living things survive and stay healthy!