Ecology Chapter: Food Chains and Webs

Food Chain and Food Web

• A food chain illustrates the flow of energy and materials in a specific ecosystem.
• Organisms often occupy multiple trophic levels across various food chains.
• A food web represents the interconnected relationships between multiple food chains.

Ecological Niche

• Consumers, organisms that cannot photosynthesize, include herbivores (plant eaters), carnivores (meat eaters), omnivores (both plant and meat eaters), scavengers (decomposers that feed on dead organisms), and detritivores (organisms that feed on detritus).
• Ecological niche defines an organism's role within an ecosystem, encompassing its diet, predation relationships, and behavioral patterns.

Pyramid of Energy

• Energy transfer between trophic levels is approximately 10% effective, meaning only 10% of energy consumed is passed to the next level.
• Energy loss occurs through heat or is utilized in biological processes, such as growth.
• The size of the energy pyramid decreases from the base to the apex due to diminished energy availability at higher trophic levels.

Pyramid of Numbers

• Represents the count of individual organisms at each trophic level within an ecosystem.
• The pyramid's structure may either increase or decrease in size as one moves from the base to the top.

Pyramid of Biomass

• Illustrates the total mass of organisms at each trophic level.
• Similar to the pyramid of numbers, it may also exhibit an increase or decrease in size from bottom to top.

Bioaccumulation

• Refers to the accumulation of toxic substances in organisms as they ascend the food chain/web.
• This phenomenon is common with pesticides and heavy metals, like mercury.
• Substances bioaccumulate because their chemical nature makes them soluble in fats and oils, leading to their retention in organisms rather than being excreted.

Food Chain and Food Web

• A food chain illustrates the flow of energy and materials in a specific ecosystem.
• Organisms often occupy multiple trophic levels across various food chains.
• A food web represents the interconnected relationships between multiple food chains.

Ecological Niche

• Consumers, organisms that cannot photosynthesize, include herbivores (plant eaters), carnivores (meat eaters), omnivores (both plant and meat eaters), scavengers (decomposers that feed on dead organisms), and detritivores (organisms that feed on detritus).
• Ecological niche defines an organism's role within an ecosystem, encompassing its diet, predation relationships, and behavioral patterns.

Pyramid of Energy

• Energy transfer between trophic levels is approximately 10% effective, meaning only 10% of energy consumed is passed to the next level.
• Energy loss occurs through heat or is utilized in biological processes, such as growth.
• The size of the energy pyramid decreases from the base to the apex due to diminished energy availability at higher trophic levels.

Pyramid of Numbers

• Represents the count of individual organisms at each trophic level within an ecosystem.
• The pyramid's structure may either increase or decrease in size as one moves from the base to the top.

Pyramid of Biomass

• Illustrates the total mass of organisms at each trophic level.
• Similar to the pyramid of numbers, it may also exhibit an increase or decrease in size from bottom to top.

Bioaccumulation

• Refers to the accumulation of toxic substances in organisms as they ascend the food chain/web.
• This phenomenon is common with pesticides and heavy metals, like mercury.
• Substances bioaccumulate because their chemical nature makes them soluble in fats and oils, leading to their retention in organisms rather than being excreted.

Explore the dynamics of food chains and food webs in ecosystems with this quiz. Understand the roles of various consumers and their ecological niches. Test your knowledge on how energy and materials flow through different trophic levels.