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ATP EducationScience Exploration Notes Class 9 English Medium 2026-27
Science Exploration Notes Class 9 English Medium 2026-27 now available for students studying in cbse school, up board, state boards and international cbse schools and Latest CBSE Curriculum based on NCERT books.
Science Exploration Notes Class 9 English Medium 2026-27
All topics of Chapter 12
1. Chapter Review and Key Points 2. Biodiversity - Classification of Living Organisms 3. Five Kingdoms Classification 4. Kingdom Monera – Unicellular Prokaryotes 5. Kingdom Protista – Unicellular Eukaryotes 6. Kingdom Fungi – Nature Decomposers 7. Kingdom Plantae – Multicellular Autotrophs 8. Kingdom Animalia – Multicellular Heterotrophs 9. Scientific Names and Taxonomic Hierarchy 10. Assignments - What Have You Learned?Science Exploration Chapter 12. Patterns in Life: Diversity and Classification
CBSE Notes New Syllabus: Class 9
Assignments - What Have You Learned?
Chapter 12. Patterns in Life: Diversity and Classification
This section explains Kingdom Animalia, the fifth kingdom in the Five Kingdom Classification. It describes the general characteristics of animals, their major groups and the gradual increase in body organisation from simple invertebrates to highly developed vertebrates.
Kingdom Animalia – Multicellular Heterotrophs
Introduction
Kingdom Animalia includes multicellular, eukaryotic organisms that obtain food from other organisms. Unlike plants, animals do not possess cell walls or chlorophyll. Most animals are capable of movement and possess specialised tissues, organs and organ systems that enable them to respond quickly to changes in their surroundings.
Characteristics of Kingdom Animalia
- Multicellular and eukaryotic organisms.
- Cells do not have a cell wall.
- Heterotrophic mode of nutrition.
- Most animals show active movement.
- Possess well-developed tissues and organ systems.
- Respond quickly to external stimuli.
- Reproduce mainly by sexual reproduction.
Habitat
Animals are found in almost every habitat on Earth.
- Forests
- Grasslands
- Mountains
- Deserts
- Freshwater
- Marine ecosystems
- Polar regions
Major Groups of Animals
Animals are broadly divided into two major groups.
| Group | Main Characteristic |
|---|---|
| Invertebrates | Animals without a backbone. |
| Vertebrates | Animals possessing a backbone or vertebral column. |
Invertebrates
Invertebrates form the largest group of animals. They do not possess a backbone and generally have a comparatively simple body organisation.
Examples:
- Sponges
- Jellyfish
- Earthworms
- Snails
- Insects
- Spiders
- Starfish
Vertebrates
Vertebrates possess an internal skeleton with a vertebral column. They have highly developed organ systems and show greater structural complexity than invertebrates.
Major Groups of Vertebrates
| Group | Main Features | Examples |
|---|---|---|
| Fish | Aquatic animals with gills and fins. | Rohu, Shark |
| Amphibians | Live both on land and in water. | Frog, Toad |
| Reptiles | Dry scaly skin; lay eggs on land. | Snake, Lizard |
| Birds | Body covered with feathers; forelimbs modified into wings. | Pigeon, Eagle |
| Mammals | Give birth to young ones and feed them with milk. | Human, Cow, Tiger |
Comparison of Invertebrates and Vertebrates
| Feature | Invertebrates | Vertebrates |
|---|---|---|
| Backbone | Absent | Present |
| Skeleton | Usually absent or external | Well-developed internal skeleton |
| Body Organisation | Comparatively simple | Highly organised |
| Nervous System | Less developed | Well developed |
| Examples | Earthworm, Insect | Fish, Bird, Mammal |
Importance of Kingdom Animalia
- Maintain ecological balance.
- Help in pollination and seed dispersal.
- Control populations of other organisms.
- Provide food, clothing and medicines.
- Support agriculture and human livelihoods.
- Contribute to biodiversity and ecosystem stability.
Summary of Kingdom Animalia
| Characteristic | Kingdom Animalia |
|---|---|
| Cell Type | Eukaryotic |
| Organisation | Multicellular |
| Cell Wall | Absent |
| Nutrition | Heterotrophic |
| Movement | Usually Active |
| Reproduction | Mainly Sexual |
ATP Education Concept Builder
Kingdom Animalia represents the highest level of body organisation among the five kingdoms. The evolutionary trend progresses from simple invertebrates without a backbone to highly developed vertebrates with complex organ systems, allowing animals to adapt to diverse habitats. This gradual increase in complexity reflects the diversity of animal life. (The uploaded pages visible so far introduce Animalia as one of the five kingdoms, while the detailed Animalia section continues in later pages of the chapter.)
ATP Education Exam Booster
- Remember the general characteristics of Kingdom Animalia.
- Differentiate between invertebrates and vertebrates.
- Learn the five major groups of vertebrates with examples.
- Know the distinguishing features of fish, amphibians, reptiles, birds and mammals.
- Understand the ecological importance of animals.
- Practise comparison-based and competency-based questions on vertebrate classification.