Introduction to Living and Non-Living Things
The world around us is filled with an endless variety of things - from animals soaring in the sky to microorganisms invisible to the naked eye, from towering trees to tiny blades of grass. Understanding what makes something "living" versus "non-living" is fundamental to the study of biology and helps us appreciate the diversity of life on Earth.
In our environment, we encounter three distinct categories of things: living beings (organisms), non-living things, and dead things. Each category has specific characteristics that set them apart, and understanding these differences is essential for students of Class 10 CBSE.
What Are Living Things and Non-Living Things?
Living Things (Organisms)
Living things, also called living beings or organisms, include all forms of plants and animals regardless of their size. These range from massive elephants and banyan trees to microscopic bacteria and viruses. Living things exhibit specific characteristics that distinguish them from non-living matter.
Examples of living things:
- Humans, elephants, dogs, cats
- Banyan trees, rose plants, grass
- Ants, butterflies, mosquitoes
- Bacteria, amoeba, paramecium
Non-Living Things
Non-living things are objects that have never possessed life. They do not have a life cycle, were never born from a parent, do not grow from within, and cannot produce offspring of their own kind. These objects exist in nature or are manufactured by humans.
Examples of non-living things:
- Rocks, stones, sand
- Glass tumblers, plastic bottles
- Motor cars, bicycles
- Water, air, metals
Dead Things (Lifeless Things)
Dead things form a special category - they once were part of living organisms but no longer show any signs of life. These objects retain some characteristics of the organism they came from but have lost all life functions.
Examples of dead things:
- Dry wood, fallen leaves
- Dry bones, leather
- Dead insects, dried fish
- Hair, nails (when separated from the body)
Characteristics of Living Things
Living organisms exhibit twelve fundamental characteristics that collectively define life. Understanding these characteristics helps distinguish living things from non-living objects.
1. Definite Shape and Size
Every living organism possesses a characteristic form and size specific to its species. While individual variations exist, these changes occur within a narrow, predictable range. A dog always looks like a dog, and an oak tree always resembles other oak trees, even though individual specimens may vary in specific dimensions.
2. Organization (Coordinated Working of Body Organs)
Living organisms consist of definite parts or organs that work together in harmony. Various organs perform their specific functions while cooperating with other organs to maintain life. This coordinated functioning is called organization. For example, in humans, the heart pumps blood, lungs facilitate breathing, and the stomach digests food - all working together to keep the body alive.
3. Cellular Organization
All plants and animals are composed of tiny structural units called cells, which can only be observed through a microscope. Cells serve as both the structural and functional units of life. Some organisms consist of a single cell (unicellular), while others contain billions of cells (multicellular). Every cell contains genetic material, cytoplasm, and a cell membrane that controls what enters and exits the cell.
4. Growth and Repair
Growth in living organisms means the addition of new body substance to existing tissues. Unlike non-living things that may increase in size through external addition (like a pile of stones growing when more stones are added), living things synthesize new material from raw materials or food within their own bodies. All organisms must grow to reach their reproductive age. Additionally, living things can repair damaged tissues, healing wounds and replacing worn-out cells.
5. Spontaneous Movement
Many living things, especially animals, move from one place to another (locomotion). They move to escape danger, catch prey, find food or shelter, and for reproduction. However, movement doesn't always mean locomotion. Even stationary organisms show internal movements.
Movement in Animals: Locomotion results from the coordinated movement of internal organs such as muscles and bones. Even microscopic organisms like amoeba show continuous movement through structures called pseudopodia (false feet). Amoeba extends its body in one direction and pulls the rest of the body forward, creating a flowing movement.
Movement in Plants: Although plants are generally stationary, they exhibit various types of movements. Roots bend toward moisture in the soil (hydrotropism), stems grow toward light (phototropism), twiners slowly wrap around supports, flower buds open at specific times, and sensitive plants (Mimosa pudica or "Lajwanti") close their leaves and droop when touched. These movements help plants survive and reproduce despite being rooted in one place.
6. Nutrition (Taking in and Utilizing Food Substances)
All living organisms require food to obtain energy and building materials for growth and repair. The methods of nutrition differ between plants and animals.
Animal Nutrition: Animals consume food in the form of complex organic substances including carbohydrates, proteins, and fats. These may come directly from plants (herbivores), from other animals that eat plants (carnivores), or from both sources (omnivores). Animals must ingest, digest, absorb, and utilize food substances.
Plant Nutrition: Most plants do not consume ready-made food. Instead, they manufacture their own food through photosynthesis. Plants absorb water and mineral salts from the soil through their roots and carbon dioxide from the atmosphere through tiny pores called stomata. Using sunlight as an energy source and chlorophyll as a catalyst, plants convert these raw materials into glucose and other carbohydrates. This process is called autotrophic nutrition, and such plants are called autotrophs.
7. Respiration (Energy Release for Body Functions)
All living organisms require energy to carry out life processes. Respiration is the process by which organisms obtain energy from food substances. Living things take in oxygen from their environment and use it to oxidize (break down) food molecules. This oxidation releases energy stored in the chemical bonds of food molecules. Simultaneously, carbon dioxide and water, which are byproducts of this process, are expelled from the body.
Respiration occurs in every living cell and continues constantly, whether the organism is active or resting. The energy released during respiration powers all body activities including movement, growth, reproduction, and maintaining body temperature.
8. Excretion (Throwing Out Body Wastes)
All body activities produce waste substances, many of which contain nitrogen and are toxic to the organism. These waste products must be removed from the body to prevent poisoning. This process of removing metabolic waste is called excretion. Living things are self-cleansing systems.
Excretion in Animals: Animals typically excrete nitrogenous waste in the form of urea, uric acid, or ammonia through specialized organs like kidneys. Waste is eliminated as urine, along with some water and salts. Other organs like skin (through sweat), lungs (carbon dioxide), and liver also participate in excretion.
Excretion in Plants: Plants eliminate waste products in several ways. They store some wastes in dead cells, excrete others as gum and resin, release oxygen during photosynthesis, and shed leaves containing accumulated wastes. Plants also use specialized cells to remove waste products or eliminate them from their entire surface.
9. Sensitivity (Response to External Stimuli)
Living organisms respond to changes in their environment. This characteristic responsiveness is also called sensitivity or irritability. Environmental changes that cause responses are called stimuli, and they include heat, light, sound, pressure, chemicals, and touch.
Examples of sensitivity:
- Plants turn toward light (phototropism)
- Animals withdraw from painful stimuli
- Pupils of eyes contract in bright light
- Sensitive plant leaves fold when touched
- Animals shiver in cold to generate heat
- Flowers open and close at specific times
This ability to respond to stimuli helps organisms survive by allowing them to react appropriately to environmental changes, threats, and opportunities.
10. Maintaining Internal Conditions (Homeostasis)
Living organisms maintain stable internal conditions despite changes in the external environment. This self-regulation is called homeostasis. Organisms regulate factors such as body temperature, pH levels, water balance, and blood sugar concentration within narrow ranges essential for survival.
Examples of homeostasis:
- Humans maintain body temperature around 37°C regardless of external temperature
- Kidneys regulate water and salt balance in the blood
- Pancreas controls blood glucose levels through insulin
- Lungs maintain proper oxygen and carbon dioxide levels
11. Reproduction (Producing Young Ones with Similar Traits)
All living organisms reproduce, creating offspring that carry characteristics similar to their parents. Reproduction ensures the continuity of species across generations. Without reproduction, a species would eventually become extinct.
Asexual Reproduction: Some organisms reproduce without involving two parents. Amoeba reproduces by binary fission - the parent cell grows and divides into two equal daughter cells. Yeast reproduces by budding - a small outgrowth forms on the parent cell, enlarges, and either separates to form a new yeast cell or gives rise to chains of buds that eventually break off.
Sexual Reproduction: Most complex organisms reproduce sexually, involving two parents. This method combines genetic material from both parents, creating offspring with traits from both while also introducing genetic variation.
12. Life Span and Death
Every living organism has a finite life span - the time interval between birth and death. This varies tremendously across species, from mere hours for some bacteria to several hundred years for certain trees. The typical life cycle involves birth, growth, maturity, reproduction, aging, and eventual death.
Even simple organisms like amoeba or bacteria have a life span. After a period of growth and metabolic activity (ranging from hours to days), these organisms divide into two new daughter cells, representing a form of "death" of the original parent organism. More complex organisms experience aging and eventual death as their body systems gradually fail.
Life span examples:
- Bacteria: Few hours to days
- Fruit flies: Few weeks
- Dogs: 10-15 years
- Humans: 70-80 years average
- Elephants: 60-70 years
- Giant tortoises: 100-200 years
- Some trees: Over 1000 years
Difference Between Living and Non-Living Things
Understanding the differences between living and non-living things is crucial for biological classification. The following comparison highlights key distinctions:
| Characteristic | Living Things | Non-Living Things |
|---|---|---|
| Cellular Structure | Made up of one or more cells | Not made of cells |
| Growth | Grow from within by synthesizing new material | May increase in size only by external addition |
| Movement | Show spontaneous movement (locomotion or internal movement) | Move only when external force is applied |
| Nutrition | Require food for energy and building materials | Do not require food |
| Respiration | Breathe and exchange gases to release energy | Do not breathe or respire |
| Excretion | Remove metabolic waste products | Do not produce or excrete waste |
| Reproduction | Produce offspring similar to themselves | Cannot reproduce |
| Response to Stimuli | Respond to environmental changes (light, heat, touch) | Do not respond to stimuli |
| Life Span | Have a definite life span; eventually die | Do not have life span; exist indefinitely unless destroyed |
| Organization | Show complex organization with coordinated organs | Lack organization and coordination |
| Adaptation | Can adapt to environmental changes over time | Cannot adapt; remain unchanged |
| Energy | Require and utilize energy for life processes | Do not require energy for existence |
Living Things and Non-Living Things Chart
Quick Reference Chart for Identification
Living Things Include:
- All plants (trees, shrubs, herbs, grasses, algae, fungi)
- All animals (mammals, birds, reptiles, amphibians, fish, insects)
- Microorganisms (bacteria, protozoa, some viruses with host cells)
Non-Living Things Include:
- Natural objects (rocks, minerals, water, air, soil, mountains)
- Manufactured objects (furniture, vehicles, buildings, tools, electronics)
- Celestial bodies (sun, moon, stars, planets)
Dead Things Include:
- Plant products (dry wood, cotton, paper, dried leaves)
- Animal products (leather, wool, silk, bones, shells)
- Preserved organic matter (fossils, dried specimens)
Classification Flow Chart
All Things Around Us
|
_____|_____
| |
Living Non-Living
| |
| _____|_____
| | |
| Natural Man-made
|
Living Things Show:
- Growth
- Movement
- Reproduction
- Respiration
- Nutrition
- Excretion
- Sensitivity
- Cellular structure
Living and Non-Living Things Worksheet
Activity 1: Classification Exercise
Classify the following items as Living (L), Non-Living (NL), or Dead (D):
- A tree in your garden: _______
- A wooden chair: _______
- A flying bird: _______
- A leather belt: _______
- A stone: _______
- A fish in an aquarium: _______
- Dried flowers: _______
- A car: _______
- Bacteria in yogurt: _______
- A plastic bottle: _______
Activity 2: Characteristic Identification
Match each characteristic with the correct living organism:
| Characteristic | Organism |
|---|---|
| Photosynthesis | A. Amoeba |
| Binary fission | B. Green plants |
| Pseudopodia | C. Sensitive plant |
| Stomata for respiration | D. Animals |
| Response to touch | E. All plants |
| Urine excretion | F. Bacteria |
Activity 3: Observation and Recording
Observe your surroundings and list:
- 5 living things you can see
- 5 non-living things you can see
- 3 dead things you can find
- One movement you observe in plants
- Two responses to stimuli in animals
Activity 4: Critical Thinking Questions
- Why is a car not considered a living thing even though it moves?
- How is growth in living things different from increase in size of non-living things?
- Can you explain why viruses are sometimes considered the "connecting link" between living and non-living things?
- A hen's egg - is it living or non-living? Explain your answer.
- What movements occur in your body even when you are sleeping?
Characteristics of Living and Non-Living Things: Detailed Comparison
Essential Life Processes
Living organisms perform all the following life processes simultaneously:
M - Movement: Ability to move body parts or the entire body
R - Respiration: Exchange of gases to release energy
S - Sensitivity: Response to environmental stimuli
G - Growth: Increase in size and mass from within
R - Reproduction: Production of offspring
E - Excretion: Removal of metabolic wastes
N - Nutrition: Intake and utilization of food
(Mnemonic: MRS GREN - helps remember all characteristics)
Non-Living Things Cannot:
- Grow on their own
- Reproduce or create copies of themselves
- Respond to environmental changes
- Carry out metabolic processes
- Repair themselves when damaged
- Maintain internal balance (homeostasis)
- Evolve or adapt over generations
Living Things and Non-Living Things Images Description
Visual Learning Guide
Images of Living Things:
-
Plant Kingdom Examples:
- Flowering plants showing growth stages
- Trees with roots, stem, leaves demonstrating organization
- Microscopic view of plant cells
- Sensitive plant (Mimosa) showing response to touch
-
Animal Kingdom Examples:
- Mammals in their natural habitat
- Microscopic organisms (amoeba with pseudopodia)
- Birds showing locomotion
- Aquatic animals demonstrating movement
-
Microorganism Examples:
- Bacteria colonies under microscope
- Yeast cells showing budding
- Amoeba during binary fission
Images of Non-Living Things:
-
Natural Non-Living Objects:
- Rocks and minerals
- Water bodies
- Mountains and landforms
- Sand and soil particles
-
Man-Made Objects:
- Vehicles and machinery
- Buildings and structures
- Tools and equipment
- Electronic devices
Images of Dead Things:
-
Plant-Derived Materials:
- Wooden furniture
- Dried leaves and flowers
- Paper and cotton fabric
-
Animal-Derived Materials:
- Leather products
- Bones and fossils
- Wool and silk
Living Things and Non-Living Things Pictures for Study
Comparative Visual Reference
Picture Set 1: Movement Comparison
- Animals running, swimming, flying (locomotion)
- Plants showing tropism (growth movement)
- Amoeba showing pseudopodial movement
- Non-living objects (stationary unless force applied)
Picture Set 2: Growth Comparison
- Seed germination to full-grown plant
- Animal life cycle stages
- Pile of rocks (no internal growth)
- Crystal formation (external addition)
Picture Set 3: Reproduction
- Animal offspring with parents
- Plant propagation methods
- Bacterial division
- Non-living objects remain unchanged
Main Concepts Summary Table
| Concept | Definition | Example |
|---|---|---|
| Living Organism | Entity that shows all characteristics of life | Humans, plants, bacteria |
| Non-Living Thing | Object that never possessed life | Rock, water, plastic |
| Dead Thing | Object that once was part of living organism | Dry wood, leather, bone |
| Cellular Organization | Structure composed of one or more cells | All living organisms |
| Photosynthesis | Process by which plants make food using sunlight | Green plants, algae |
| Respiration | Process of releasing energy from food | All living organisms |
| Homeostasis | Maintenance of stable internal conditions | Body temperature regulation |
| Autotrophs | Organisms that make their own food | Green plants, some bacteria |
| Heterotrophs | Organisms that consume other organisms for food | Animals, fungi, most bacteria |
| Life Span | Time period from birth to death | Varies by species |
Important Terms and Definitions
Anabolism: The metabolic process that builds up complex molecules from simpler ones, requiring energy.
Catabolism: The metabolic process that breaks down complex molecules into simpler ones, releasing energy.
Metabolism: The sum of all anabolism and catabolism processes occurring in living organisms.
Chlorophyll: The green pigment in plants that captures light energy for photosynthesis.
Stimuli: Environmental changes that cause responses in living organisms (heat, light, touch, sound, pressure).
Irritability: The ability of living organisms to respond to stimuli; also called sensitivity.
Locomotion: Movement of an organism from one place to another.
Binary Fission: Asexual reproduction in which a single organism divides into two equal parts.
Budding: Asexual reproduction in which a new organism develops as an outgrowth from the parent.
Pseudopodia: Temporary projections of cytoplasm used by some organisms like amoeba for movement and feeding.
Stomata: Tiny pores on plant leaves through which gas exchange occurs.
Hydathodes: Structures in plants through which excess water is eliminated.
Phototropism: Growth or movement of plants toward light.
Hydrotropism: Growth or movement of plant roots toward water.
Special Cases and Exceptions
Viruses: The Connecting Link
Viruses occupy a unique position between living and non-living things. They exhibit characteristics of both:
Living Characteristics of Viruses:
- Contain genetic material (DNA or RNA)
- Reproduce (only inside host cells)
- Undergo mutations and evolution
- Show specificity in host selection
Non-Living Characteristics of Viruses:
- Cannot reproduce independently
- No cellular structure
- No metabolism outside host cells
- Can be crystallized like non-living chemicals
- Do not grow or respond to stimuli independently
Seeds: Living or Non-Living?
Seeds appear lifeless but are actually living structures in a dormant state. They contain a living embryo that can germinate when conditions are favorable. Although they show minimal metabolic activity during dormancy, they possess all the potential characteristics of life.
Fire: Why Not Living?
Fire might seem alive because it moves, grows, and "reproduces" (spreads), but it lacks essential characteristics of life:
- No cellular structure
- Cannot reproduce itself (requires fuel)
- No metabolism or excretion
- Cannot respond to stimuli
- No genetic material
Practical Applications and Importance
Why Study Living and Non-Living Things?
-
Scientific Classification: Understanding what constitutes life helps in classifying new discoveries and organisms.
-
Medical Science: Identifying living microorganisms helps in disease diagnosis and treatment.
-
Environmental Conservation: Recognizing living organisms helps in preserving biodiversity and ecosystems.
-
Agriculture: Understanding plant characteristics aids in crop improvement and disease management.
-
Space Exploration: Defining life helps scientists search for extraterrestrial organisms.
-
Biotechnology: Knowledge of living characteristics enables genetic engineering and biotechnology applications.
CBSE Exam Preparation Tips
Important Topics to Focus On
- All twelve characteristics of living things with examples
- Differences between living, non-living, and dead things
- Types of movements in plants and animals
- Nutrition methods (autotrophic and heterotrophic)
- Reproduction in simple organisms (amoeba, yeast)
- Concept of homeostasis
- Life span and its variation across species
Common Exam Questions
Subjective Questions:
- List five characteristics that distinguish living things from non-living things. Explain each with an example.
- Describe the different types of movements observed in plants.
- Explain reproduction in amoeba with a labeled diagram.
- Why are viruses considered the connecting link between living and non-living things?
- How do plants excrete waste products?
Objective Questions:
- The structural and functional unit of life is: (a) Tissue (b) Organ (c) Cell (d) System
- Plants respire through: (a) Stomata (b) Trachea (c) Gills (d) Lungs
- The sum of anabolism and catabolism is called: (a) Excretion (b) Metabolism (c) Homeostasis (d) Respiration
Diagram Practice
Students should practice drawing and labeling:
- Amoeba showing pseudopodia movement
- Amoeba reproducing by binary fission
- Yeast budding
- Sensitive plant (open and closed leaf positions)
- Cross-section of a leaf showing stomata
Additional Resources for Practice
Recommended Study Materials
- NCERT Biology Textbook Class 10 - Chapter on Life Processes
- Reference Books - Lakhmir Singh Biology, S. Chand Biology
- Online Resources - Educational videos on cellular organization and life processes
- Laboratory Activities - Microscope observation of living cells
Self-Assessment Questions
Short Answer Questions:
- What is cellular organization?
- Define homeostasis with an example.
- Name two excretory products of plants.
- What is the difference between growth and repair?
- Explain sensitivity in living organisms.
Long Answer Questions:
- Describe in detail the twelve characteristics of living things.
- Compare and contrast living things and non-living things with suitable examples.
- Explain the process of nutrition in plants and animals.
- Discuss the importance of respiration in living organisms.
- Why is reproduction essential for the continuity of species?
Conclusion
Understanding the distinction between living and non-living things forms the foundation of biological sciences. Living organisms exhibit remarkable characteristics including cellular organization, growth, movement, nutrition, respiration, excretion, sensitivity, homeostasis, and reproduction. These characteristics work together to maintain life and ensure species continuity.
By mastering these concepts, students develop a deeper appreciation for the complexity and wonder of life. This knowledge not only helps in academic success but also fosters environmental awareness and scientific thinking essential for future innovation and discovery.