Biotic components

• The word 'biotic' means 'living'.
• Biotic components have life.
• Plants, animals, scavengers, and decomposers are biotic components.

Biotic and abiotic components of the environment

Plants:

• Most plants that we see around us have green leaves.
• Leaves are green because they contain a green substance called chlorophyll (chloro, green; phyll, leaf).

• Chlorophyll gives plants the special ability to make their own food using sunlight, water, and carbon dioxide.
• Non-green plants do not have chlorophyll and, therefore, cannot make their own food. They depend on other plants and animals for their food.

• The process by which green plants make their food using carbon dioxide and water in the presence of sunlight and chlorophyll is called photosynthesis.

Animals:

• Animals cannot make their own food, as green plants.
• They are thus said to be heterotrophs.
• Both animals and plants need certain substances called nutrients in order to grow.
• Plants absorb nutrients such as nitrogen, phosphorus, and calcium from the soil.
• These nutrients enter the bodies of animals when they eat plants or other animals.
• They reach back to the soil, after their bodies decompose.

Scavengers and Decomposers:

• There are some organisms in nature that feed on the bodies of dead plants and animals and release the nutrients trapped inside them.
• Animals that feed on the dead bodies of other animals are called scavengers.
• For example, hyena and vulture
• Tiny organisms that feed on the bodies of dead plants and animals and break them down into simpler substances are called decomposers.
• Bacteria and fungi are common decomposers.

Fungi is a decomposer and vulture is a scavenger

• The nutrients released from the dead bodies by the action of scavengers and decomposers get mixed with the soil and are again absorbed by plants. This process is called recycling of nutrients.
• Scavengers and decomposers play two important roles in the environment as:

1. They keep the environment clean by removing the bodies of dead plants and animals.
2. They help in the recycling of nutrients in the environment.

Interactions among Biotic Components:

• Plants and animals depend on each other for various needs.
• Animals mainly depend on plants for food and shelter.
• Animals in turn help plants by pollinating flowers, dispersing seeds, etc.

Interactions among Biotic Components

• In nature, the following relationships are observed among plants, animals, scavengers, and decomposers.
• Plants utilize solar energy and manufacture their own food through photosynthesis. They are called producers.
• Herbivores such as rabbit and deer that feed on plants are called primary consumers.
• Carnivores such as tiger and lion that feed on herbivores are called secondary consumers.
• Omnivores such as human being and bear feed on both plants and other animals. They are also secondary consumers.
• Scavengers and decomposers feed on dead plants and animals and release the nutrients trapped inside their bodies into the soil.
• These nutrients are then absorbed by plants, which helps them to grow and manufacture food.