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If you visit Rishikesh, you will see hilly mountains and yaks, while in Rajasthan, you will see sandy deserts and camels. The living organisms’ characteristics and habitats help classify them into different groups. The living organisms and their surroundings vary, and hence there is adaptation. Characteristics of organisms distinguish them from non-living objects. Organisms and the surroundings where they live help categorise them under different groups. Habitat and adaptation help us study the diversity in these organisms. A journey through habitat helps study the variations. Characteristics of living organisms include movement, nutrition, reproduction, growth, and response to stimuli.
You might observe that different organisms have different surroundings, and hence they have different body structures. Habitats are the natural surroundings in which an organism lives. To survive in different habitats, organisms must develop some features or habits termed adaptation.
In the ecosystem, you will observe many objects. The living components like plants and animals in the ecosystem are termed biotic components, while non-living components like soil, water, and air are called abiotic components.
If the habitat of an organism is land, it is called a terrestrial habitat. For example, forests, grasslands, deserts, mountains, and coastal areas. While the animals and plants that live in water are said to live in aquatic habitats. For example, ponds, lakes, rivers, and oceans.
You might have seen many living organisms on land, such as horses, camels, sheep, etc. The habitat on the land is termed a terrestrial habitat, and includes deserts, grasslands, mountains, and forests.
Deserts have large amounts of sand but low amounts of water. Desert plants have thick stems with thick waxy layers and thorns to reduce water loss by transpiration. Desert animals like camels, snakes, and rats are adapted to living in high temperatures and less water. Rats and snakes live in burrows during the day and come out at night when it is cooler.
Mountains are very cold and windy due to high altitude and snowfall, so the animals and plants must be protected against this. Animals like snow leopards, yaks, and goats have thick skin (fur) and long hair on their body to provide insulation from cold. Trees like the Pinus are cone-shaped with needle-like leaves so that snow and rainwater can slide off easily.
The wild animals living in the grasslands or forests have brown colour bodies (protecting them from prey), long claws, and strong forelimbs to catch the prey (deer). Herbivores like deer have strong teeth to chew hard stems, strong limbs, and long ears to protect them from predators (lions).
Look at a fish. You will see that it has a streamlined body. Squids and octopuses live deep in the ocean, near the seabed to catch the prey. These aquatic animals use dissolved oxygen in water with the help of gills. You might have seen dolphins and whales coming on the water surface to breathe. They have blow holes so that they can breathe in the air when they come on the water surface.
Ponds and lakes
You might have seen lotus floating on the ponds. Its roots are reduced while the stem is long and hollow. Such aquatic plants float on water, while some of them are submerged in water. Frogs around the ponds have webbed feet, strong back legs to hop, and can live both on land and water.
If you visit a forest, you will see various objects in your vicinity like trees, birds, animals, soil, water, dry leaves, dead animals, mushrooms, and many more. There are some characteristics to distinguish between living and non-living objects.
Can you live without food for a long time? No, because living organisms cannot live without food. Plants prepare the food by photosynthesis, while animals depend on others for nutrition. Food provides them with nutrition and the energy to grow.
As you become old, your body grows but does your badminton racket too after many years? No, because growth is the characteristic of living organisms. If you sow seed in the soil and water it, it will grow into a plant and eventually into a tree.
We need to respire so that our body gets enough oxygen to take energy from the food while non-living objects do not. Humans breathe by lungs, earthworms by skin, and fishes by gills. You will be surprised to know that the plants breathe through tiny holes present in their leaves.
Response to External Stimuli
What happens when you touch a hot object, you quickly draw your hands back. Have you touched the leaves of the touch-me-not plant? The leaves droop off. These factors (heat and touch) are the external stimuli to which the living organisms respond.
Since nutrition is important for living organisms, removing undigested food or waste from the body (excretion) is also very important. All living organisms get rid of waste in different ways.
All the living organisms give birth to their young ones by the process of reproduction. Animals and plants give birth to their kind, while non-living objects cannot do so.
Non-living objects cannot move while living objects can move on their own. You might be wondering about plants. Plants are anchored to their surface, but water and minerals move in their body. Animals move in search of food and shelter
All living organisms tend to live in their natural habitats. According to their habitat, they adapt for survival. All living organisms show certain characteristics that differentiate them from non-living objects. Hence, by studying these characteristics, we can easily differentiate between living and nonliving things around us.
The surrounding conditions in which the organism lives, whether air, water, or land, are generally termed its habitat.
The surrounding of the organism to which it is naturally adapted is called its habitat.
According to the habitat, organisms must make changes in their body for survival. For example, the cactus has cuticles on its surface, and camels store water in their hump to live in the desert.
Characteristics of living organisms are nutrition, growth, respiration, response to stimuli, excretion, reproduction, and movement.
The living part of the ecosystem is called the biotic component. For example, plants, animals, etc.
An organism is a living creature that exhibits characteristics like growth, reproduction, respiration, response to external stimuli, etc.
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