Introduction
Living organisms are all creatures that grow, move, reproduce, and respond to their surroundings. Studying living organisms helps us understand their structure, habits, and the environments they live in.
Characteristics of Living Organisms
Living organisms share certain features that distinguish them from non-living things:
- Movement – Most living organisms can move, either entirely or parts of their body.
Example: Animals move from one place to another; plants show movement of leaves or stems. - Respiration – Process of obtaining energy by breaking down food.
Example: Humans breathe in oxygen to release energy from food. - Nutrition – All living organisms need food for growth and energy.
Example: Animals eat plants or other animals; plants make food through photosynthesis. - Growth – Living organisms increase in size and complexity.
Example: A baby grows into an adult. - Reproduction – Living organisms produce offspring to continue their species.
Example: Humans, birds, and plants reproduce in different ways. - Sensitivity/Response to Stimuli – Ability to respond to changes in the environment.
Example: Plants bend toward sunlight; humans pull back from a hot object. - Excretion – Removal of waste products from the body.
Example: Humans excrete urine; plants release oxygen.
Habitats of Living Organisms
A habitat is the natural place where an organism lives and grows. Different organisms are adapted to different habitats.
- Terrestrial Habitat – Land-based habitats.
Example: Forests, grasslands, deserts.
Animals: Lion, elephant, tiger
Plants: Trees, shrubs, grasses - Aquatic Habitat – Water-based habitats.
Example: Ponds, rivers, lakes, oceans
Animals: Fish, frog, whale
Plants: Hydrilla, algae, water lilies - Aerial Habitat – Organisms that live in the air.
Example: Birds, butterflies, bats
Adaptations of Organisms
- Structural adaptations – Physical features that help survive.
Example: Fish have gills; birds have wings. - Behavioral adaptations – Actions that help survive.
Example: Birds migrate in winter; nocturnal animals are active at night.
Summary
- Living organisms move, grow, reproduce, respire, and respond to stimuli
- Habitats include terrestrial, aquatic, and aerial
- Adaptations help organisms survive in their habitats
Important Questions (Short Answers)
1. What is a living organism?
A creature that grows, moves, reproduces, and responds to its surroundings.
2. Name any three characteristics of living organisms.
Movement, growth, reproduction.
3. What is respiration?
Process of obtaining energy by breaking down food.
4. What is nutrition?
Process of taking in food to get energy and grow.
5. Give one example of movement in plants.
Leaves bending toward sunlight.
6. Give one example of movement in animals.
A cat walking or running.
7. What is reproduction?
Process of producing offspring.
8. What is sensitivity?
Ability to respond to changes in the environment.
9. Give one example of excretion in humans.
Excretion of urine.
10. What is a habitat?
The natural place where an organism lives and grows.
11. Name three types of habitats.
Terrestrial, aquatic, aerial.
12. Give one example of a terrestrial animal and plant.
Animal: Lion
Plant: Mango tree
13. Give one example of an aquatic animal and plant.
Animal: Fish
Plant: Hydrilla
14. Give one example of an aerial animal.
Bird or butterfly.
15. What are structural adaptations?
Physical features that help an organism survive.
Example: Fish have gills.
16. What are behavioral adaptations?
Actions that help organisms survive.
Example: Birds migrate in winter.
17. Why do organisms need adaptations?
To survive in their habitats.
18. How do plants respond to sunlight?
Leaves bend toward sunlight.
19. What is the main difference between terrestrial and aquatic habitats?
Terrestrial habitats are on land; aquatic habitats are in water.
20. Why is movement important for living organisms?
For finding food, escaping danger, and survival.