Science Exploration Notes Class 9 English Medium 2026-27

Science Exploration Chapter 3. Tissues in Action

CBSE Notes New Syllabus: Class 9

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Chapter 3. Tissues in Action

Cells are the basic units of life, but in multicellular organisms, similar cells work together to perform specific functions. Such groups of similar cells form tissues. Different tissues combine to form organs, organ systems and finally a complete organism. This chapter explains the organisation of plant and animal tissues, their structure, functions and importance in maintaining life processes.

Chapter Overview

• Hierarchy of Organisation – Cells combine to form tissues, tissues form organs, organs form organ systems, and organ systems together form an organism.
• Tissues – A tissue is a group of similar cells that work together to perform a specific function.
• Division of Labour – Different tissues perform specialised functions, making the body more efficient.
• Plant and Animal Tissues – Plants and animals possess different tissues because their lifestyles and functions are different.
• Meristematic Tissue – These are actively dividing tissues responsible for the growth of plants.
• Types of Meristematic Tissue – Apical, lateral and intercalary meristems help plants grow in length, girth and regeneration.
• Permanent Tissue – Formed when meristematic cells lose the ability to divide and become specialised.
• Simple Permanent Tissue – Parenchyma, collenchyma and sclerenchyma provide storage, flexibility and mechanical support.
• Complex Permanent Tissue – Xylem transports water and minerals, while phloem transports food throughout the plant.
• Tissue Systems – Dermal, ground and vascular tissue systems work together to protect, support and conduct materials in plants.
• Animal Tissues – Animal tissues are classified into epithelial, connective, muscular and nervous tissues.
• Epithelial Tissue – Covers body surfaces, protects organs and performs absorption, secretion and exchange.
• Connective Tissue – Supports, connects and protects body parts. Blood, bone, cartilage, tendon and ligament are its major types.
• Muscular Tissue – Responsible for movement and includes skeletal, smooth and cardiac muscles.
• Nervous Tissue – Receives, processes and transmits nerve impulses through neurons.
• Musculoskeletal System – Bones, muscles, tendons, ligaments and joints work together to provide movement and support.

Key Terms to Remember

Learning Outcomes

• Understand the organisation of cells into tissues and organs.
• Differentiate between plant tissues and animal tissues.
• Explain the structure, location and functions of different plant tissues.
• Describe the characteristics and functions of animal tissues.
• Understand the role of tissue systems in plants.
• Relate the structure of tissues with their specialised functions.
• Explain how muscles, bones and nerves work together for movement.
• Apply the concept of tissues to daily life and biological processes.

Why This Chapter is Important

• Forms the foundation for higher studies in Plant Physiology and Human Physiology.
• Frequently tested in CBSE Board examinations through competency-based and case-study questions.
• Helps understand growth, repair, movement and coordination in living organisms.
• Builds the basic concepts required for Genetics, Biotechnology and Medical Science.

ATP Education Quick Revision

• Cells → Tissues → Organs → Organ Systems → Organism
• Plant Tissues → Meristematic and Permanent Tissues.
• Permanent Tissues → Simple and Complex.
• Animal Tissues → Epithelial, Connective, Muscular and Nervous.
• Xylem → Water Transport.
• Phloem → Food Transport.
• Neuron → Carries Nerve Impulses.
• Skeletal Muscle → Voluntary Movement.
• Smooth Muscle → Involuntary Movement.
• Cardiac Muscle → Heartbeat.

ATP Education Exam Tip: Focus on the differences between plant and animal tissues, meristematic and permanent tissues, xylem and phloem, epithelial and connective tissues, and the characteristics of skeletal, smooth and cardiac muscles. These concepts are highly important for objective, competency-based and descriptive questions. The chapter emphasizes that specialised tissues perform specialised functions, making multicellular organisms more efficient. :contentReference[oaicite:0]{index=0}