Question

From what does a Grazing food chain typically start?

• A. Dead organic matter
• B. Saprophytic organisms
• C. Living green plants
• D. Carnivores

Answer 1

Answer:

C. Living green plants

Understanding the Grazing Food Chain

• A grazing food chain is a type of food chain that starts with living green plants, which are also known as producers.
• These producers are organisms that can synthesize their own food, primarily through photosynthesis, converting light energy into chemical energy.
• The energy captured by these green plants then flows to the next trophic level, which are the primary consumers or herbivores.
• Herbivores directly feed on the living green plants. Examples include deer, rabbits, grasshoppers, and cattle.
• From herbivores, the energy moves to secondary consumers (carnivores that eat herbivores) and then to tertiary consumers (carnivores that eat other carnivores).
• This chain represents the direct consumption of living biomass.

Key Characteristics and Facts for Competitive Exams:

• Energy Source: The primary source of energy for a grazing food chain is solar energy, captured by producers.
• Trophic Levels: It typically involves multiple trophic levels: Producers → Primary Consumers → Secondary Consumers → Tertiary Consumers.
• Dominant Food Chain: In most ecosystems, the grazing food chain is the dominant pathway for energy flow.
• Contrast with Detritus Food Chain: Unlike the grazing food chain, a detritus food chain starts with dead organic matter (detritus) and involves decomposers like bacteria and fungi. Both chains are interconnected.
• 10% Law (Lindeman's Law): Only about 10% of the energy from one trophic level is transferred to the next trophic level; the rest is lost, primarily as heat, according to the Lindeman's 10% Law of energy transfer. This explains why food chains rarely have more than 4-5 trophic levels.
• Ecosystem Stability: The health and productivity of the grazing food chain are crucial for the overall stability and energy flow within an ecosystem.