7.4.1 Trophic Levels

1. Level 1: Producers

• Organisms at the first trophic level are called producers.
• These are typically plants and algae, which make their own food through photosynthesis.

2. Level 2: Primary Consumers

• Organisms at the second trophic level are known as primary consumers.
• These are herbivores that feed exclusively on producers (plants).

3. Level 3: Secondary Consumers

• Organisms at the third trophic level are called secondary consumers.
• These are carnivores that eat primary consumers (herbivores).

4. Level 4: Tertiary Consumers

• Organisms at the fourth trophic level are known as tertiary consumers.
• These are carnivores that eat other carnivores, specifically secondary consumers.
• Apex predators are at the top of the food chain with no natural predators.

Decomposers

• Role: Decomposers, such as bacteria and fungi, break down dead plant and animal matter, recycling nutrients back into the ecosystem.
• Process: They secrete enzymes that break down complex organic material into small, soluble molecules.
• Absorption: These soluble molecules are then absorbed into the decomposers through diffusion.