Science Class 9 - Diversity In-Living-Organisms Notes

Diversity in Living Organisms

In this chapter, you will learn about the vast variety of living organisms found on Earth, how they are classified, and why this diversity is important. By the end of this chapter, you will understand the basic groups of living things and how scientists organize them.

Introduction

The world is full of different living organisms. Some are tiny, like bacteria, while others are huge, like elephants and trees. This variety is called diversity. Scientists study and classify living things to understand them better.

Why is Diversity Important?

• It helps maintain balance in nature.
• Different organisms have different roles in the environment.
• Diversity provides food, medicine, and other resources.

Classification of Living Organisms

Scientists classify living things into groups based on their similarities and differences. This makes it easier to study and understand them.

• Kingdoms: The broadest groups. The main kingdoms are Plantae, Animalia, Fungi, Protista, and Monera.
• Phylum, Class, Order, Family, Genus, Species: These are smaller groups within kingdoms.

Major Groups of Living Organisms

• Plants: Make their own food using sunlight. Examples: Mango tree, rose, grass.
• Animals: Cannot make their own food. Examples: Lion, fish, butterfly.
• Fungi: Absorb food from other sources. Examples: Mushroom, yeast.
• Protists: Mostly single-celled organisms. Examples: Amoeba, paramecium.
• Monera: Includes bacteria. Examples: Lactobacillus, cyanobacteria.

How Are Organisms Classified?

• Based on cell type (prokaryotic or eukaryotic)
• Number of cells (unicellular or multicellular)
• Mode of nutrition (autotrophic or heterotrophic)
• Body structure and functions

Fun Activity: Observe Diversity!

Look around your garden or park. List five different plants and five different animals you see. Notice how they are different from each other.

Summary

• Living organisms are very diverse.
• Classification helps us study and understand living things.
• There are five main kingdoms of living organisms.

Practice Questions

1. What is meant by diversity in living organisms?
2. Name the five kingdoms of living organisms.
3. Give two examples of fungi.
4. Why do scientists classify living things?
5. What is the difference between plants and animals?

Challenge Yourself

• Draw a chart showing the five kingdoms and write one example for each.
• Find out the scientific name of your favorite animal or plant.

Did You Know?

• There are millions of species of living organisms on Earth!
• The scientific system of naming organisms is called binomial nomenclature.

Glossary

• Diversity: Variety or differences among living things.
• Classification: Grouping things based on similarities and differences.
• Kingdom: The largest group in classification.
• Species: A group of similar organisms that can reproduce.

Answers to Practice Questions

1. The variety of living things found on Earth.
2. Plantae, Animalia, Fungi, Protista, Monera.
3. Mushroom, yeast.
4. To make it easier to study and understand them.
5. Plants make their own food; animals cannot make their own food.

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Explore the diversity around you and learn how living things are grouped!