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title: "Structural Organisation in Animals"
board: "CBSE"
curriculum: "CBSE"
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subject: "Biology"
book: "Biology"
chapter: "Structural Organisation in Animals"
chapter_slug: "structural-organisation-in-animals"
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# Structural Organisation in Animals
This chapter focuses on the structural organisation in animals, emphasizing the functions of cells in multicellular organisms. It highlights how various cell types collaborate to form tissues, which in turn combine to create organs and organ systems, enhancing the efficiency of physiological functions.

---

## Knowledge Snapshot
| Field | Details |
| :--- | :--- |
| Class | Class 11 |
| Subject | Biology |
| Book | Biology |
| Chapter | Structural Organisation in Animals |
| Pages | 79-84 |

---

## Chapter Summary
### Short Summary
The chapter elucidates the organisation of cells into tissues, organs, and systems in multicellular animals using frogs as a representative example. It covers the essential structures and functions associated with various organ systems.

### Detailed Summary
The chapter begins by contrasting unicellular and multicellular organisms, particularly in their functional complexity. It explains that multicellular organisms have cells organised into tissues that perform specific roles, which combine to form organs and organ systems. The functioning of organs is illustrated using frogs, detailing their morphology and anatomy, including the digestive, circulatory, respiratory, nervous, excretory, and reproductive systems. Each of these systems is described in terms of its components and functions.

---

## Topic-Wise Explanation
### Organ and Organ System
Organ systems in multicellular beings consist of various organs that function together for enhanced efficiency, organized from four basic tissue types.

### Frogs
Frogs, as members of the class Amphibia, demonstrate unique physiological traits including cold-bloodedness and seasonal behaviour adaptations like aestivation and hibernation.

### Morphology
The external structure of frogs includes smooth, moist skin, forelimbs and hind limbs adapted for various locomotions, and distinct sexual dimorphism.

### Anatomy
Frogs possess complex internal organ systems including a short digestive tract suited for a carnivorous diet, well-developed respiratory organs, an efficient circulatory system, and defined excretory and reproductive structures.

### Digestive System
The digestive system is comprised of a simplified alimentary canal facilitating the rapid digestion and absorption of nutrients, aided by various glands.

### Circulatory System
The frog’s circulatory system is a closed system with a three-chambered heart that efficiently pumps blood to various body parts, integrating a hepatic and renal portal system.

### Nervous System
The nervous system includes a central nervous system and peripheral nerves, regulating body functions and responses to environmental stimuli.

---

## Core Ideas
| Idea | Explanation |
| :--- | :--- |
| Cellular Organisation | Cells are organized into tissues, organs, and organ systems for efficient functioning in multicellular organisms. |
| Morphology vs Anatomy | Morphology studies the external form, while anatomy focuses on internal structures of organisms. |

---

## Key Concepts
| Concept | Meaning |
| :--- | :--- |
| Tissue | A group of similar cells performing a specific function. |
| Amphibia | Class of animals including frogs, characterized by a dual life in water and on land. |

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## Important Points for Revision
* Multicellular organisms have varied cell types performing specialized functions.
* Tissues combine to form organs, which work together as organ systems.
* Frogs exhibit adaptations for both aquatic and terrestrial life.
* The digestive system of frogs is short due to their carnivorous diet.
* Frogs breathe through skin and lungs, depending on the environment.
* Their circulatory system features a three-chambered heart.
* Frogs are ureotelic, excreting urea through a well-developed excretory system.
* Fertilization in frogs is external, occurring in water.
* Frogs play a vital role in ecological balance and pest control.

---

## Practice Questions
### Short Answer Questions
1. What is the primary function of epithelial tissue in frogs?
2. Describe the role of the liver in the frog's digestive system.
3. How do frogs adapt to extreme environmental conditions?
4. What distinguishes male frogs from female frogs?
5. Explain the significance of the hepatic portal system in frogs.

### Long Answer Questions
1. Describe the anatomy and function of the frog's circulatory system in detail.
2. Discuss the morphological features of frogs and how they aid in their survival in both aquatic and terrestrial environments.
3. Analyze the evolutionary trends observed in the organ systems of frogs compared to other vertebrates.

---

## Source Attribution
| Field | Value |
| :--- | :--- |
| Source | Edzy |
| Reference Type | examSubjectBookChapter |
| Reference ID | 66f145940821118bf5c5e3bc |
| Canonical URL | https://www.edzy.ai/cbse-class-11-biology-structural-organisation-in-animals |
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