MS Science-Biomes and Ecosystems: Energy, Primary Producers & Comsumers

An energy pyramid is a graphical model of energy flow in a community. The different levels represent different groups of organisms that might compose a food chain. From the bottom-up, they are as follows:

• Producers (or autotrophs)  — bring energy from nonliving sources into the community.
• Primary consumers — eat the producers, which makes them herbivores in most communities.
• Secondary consumers — eat the primary consumers, which makes them carnivores.
• Tertiary consumers — eat the secondary consumers, they may be.
• Decomposers  — operate at each trophic level, organism that breaks down plants, animals and waste matter. Fungi and becteria are decomposers.

Energy pyramid depicts the energy is minimum as the highest trophic level and is maximum at the lowest trophic level. At each trophic level, there is successive loss of energy in the form of heat and respiration, etc. Other than this, there are also:

• Pyramid of numbers — depicts the relationship in terms of the number of producers, herbivores and the carnivores at their successive trophic levels.
• Pyramid of biomass — represents the relative amounts of biomass at each trophic level.

Living systems rely on energy to operate. Sunlight is the ultimate energy source on Earth. Organisms that capture sunlight or other chemicals and transform it into any form of energy are called autotrophs. Autotrophs are also known as primary producers. These organisms are important for the flow of energy within the biosphere.

Photosynthesis is the process where most primary produces capture the energy from sunlight to power chemical reactions. These reactions are beneficial to other organisms because it convert water and carbon dioxide into oxygen and carbohydrates, such as starch and sugar.

Photosynthesis is the process where most primary produces capture the energy from sunlight to power chemical reactions. These reactions are beneficial to other organisms because it convert water and carbon dioxide into oxygen and carbohydrates, such as starch and sugar.

Miller, Kenneth R., and Joseph S. Levine. "Chapter 3: The Biosphere." Miller & Levine Biology. Boston, MA: Pearson, 2010. N. pag. Print.

Organisms that rely on other organisms for energy are called heterotrophs, or consumers. This imply that heterotrophs do not produce energy by their own. 

* Some organisms might fall in more than one category -- depends on their environment. "Hyenas (carnivores) will scavenge (scavengers) if they get a chance."

Types of Consumers:
 

• Carnivores- Kill and eat other animals (Wolves)
• Herbivores- Gain energy by eating plants, fruits, leaves, seeds, or roots (Deer)
• Scavengers- Obtain energy through the carcasses of other dead animals (The King Vulture)
• Omnivores- Eat other animals and plants to receive energy (Humans!!)
• Decomposers- Organisms that are fed by chemically breaking down organic components (Mushrooms)
• Detritivores- Simply eat detritus particles by chewing or grinding (Earthworms)

Miller, Kenneth R., and Joseph S. Levine. "Chapter 3: The Biosphere." Miller & Levine Biology. Boston, MA: Pearson, 2010. N. pag. Print.