The Living Organisms: Characteristics and Habitats

A habitat is a place where organisms live. All the needs that are required for the survival of organisms like food, water, air, shelter, etc. are provided by a habitat. The same habitat may be shared by multiple types of plants and animals.

Broad Classification of Habitat:

• Terrestrial: Related to land. E.g., forests, grasslands, deserts, coastal and mountain regions.
• Aquatic: Related to water. E.g., Lakes, rivers, and oceans.

Components of Habitat:

• Biotic (living): Plants, animals, and microorganisms.
• Abiotic (Non-living): Rocks, soil, air, water, light, and temperature.

The presence of specific features and habits, due to which an organism is able to live in a particular habitat, is called Adaptation. Those organisms which cannot adapt to changes die, and only the adapted ones survive i.e., “Survival of the fittest.“

Some Terrestrial Habitats and Adaptations:

1.     Deserts: Organisms need adaptations to cope with issues such as heat and water scarcity.

•         Camels:
• Long legs keep the body away from the hot sand.
• They excrete small amounts of urine, dung is dry, and they do not sweat.
•         Rats and Snakes:
• Stay in sand inside the deep burrow.
• As night is cooler, they come out only at night.
•         Plants:
• Leaves are either absent, in the form of spines or very small.
• Because of the scarcity of water, desert plants usually don’t have leaves. They do Photosynthesis by their stems. E.g., Cactus, etc.
• The stem is also covered with a thick waxy layer to retain water in the tissues.
• Succulents have parts that are thickened, fleshy, and engorged to store water.
•         Roots are usually very deep into the soil for absorbing water.

1. Mountainous regions: Organisms also need adaptations to cope with very cold and windy environments including snowfall.

•         Trees:
• Cone-shaped and have sloping branches.
• Mountainous plants have spiky leaves to slip off rainwater and snow easily.
•         Animals:
• Thick skin or fur e.g., Yaks, Snow leopard, etc.
• Mountain goats have strong hooves that help them in running on the rocky slopes.

1.   Grasslands

•         Lion:
• Long claws to catch prey (animals to eat).
• Its light brown colour hides in dry grasslands.
• Front eye helps them in detecting prey.
•         Deer:
• Strong teeth for chewing hard plant stems.
• Long ears to hear movements of predators (like lions etc).
• They have eyes on the side of their head to watch in all directions for danger.
• Deer run very fast, which helps them to run off from the predators.

Some Aquatic Habitats and Adaptations

1.   In Oceans:

• Sea animals have streamlined bodies to flow easily.
• Animals like squids and octopuses which do not have streamlined bodies stay deeper in the ocean.
• Animals usually have gills to use oxygen dissolved in water.
• Dolphins and whales that do not have gills breathe in air through nostrils or blowholes. They come out to the surface to breathe in air.

1.     In ponds and lakes:

• Roots are fixed in the soil below the water to hold the plant.
• Stems are long, hollow, and light to grow up to the surface of the water.
• Leaves and flowers of the ponds and lake’s plants float on the surface of the water.
• Submerged plants have narrow and thin ribbon-like leaves which can bend in the flowing water.
• Frogs have webbed feet which help them swim in the water.

Characteristics of Organisms

Living things have some common characteristics: They need food for energy and minerals, do respiration and excretion, respond to their environment, reproduce, grow, and show movement.

• Food: Gives organisms the energy needed for them to grow and sustain life processes.
• Growth: There are different stages of growth. e.g., Newborn human baby to adult.
• Breathing: Breathing is one of the parts of the process called Respiration. Through the process of respiration, the body obtains energy from food.

• Earthworms breathe through their skin.
• Fishes use their special organ gill to use oxygen dissolved in water.
• Plant leaves take in air through tiny pores.

• Respond to Environment: 

• The Changes in our surroundings that make us respond are called stimuli. e.g., cockroaches running away from extreme light, etc.
• Flowers of plants either bloom at night or close after sunset.
• Plants like Mimosa, commonly known as ‘touch-me-not’, leaves close or fold when someone touches it.

• Excretion: The process of getting rid of wastes by organisms is known as Excretion. 
• Reproduce: 

• Animals produce their young ones through eggs or give birth to the young ones.
• New plants grow through seeds that are produced by the plants.
• There are some Plants that reproduce through other parts in place of seeds. e.g., a part of a potato with a bud grows into a plant. Plants also reproduce through cuttings like Rose.

In general, something that is living may have all the above characteristics, while non-living things may not show all these characteristics at the same time.