Energy Transfer

Energy Transfer

Trophic Categories

• All animals have their place in the ecosystem

• Not every plant, bacteria or animal is the same in the ecosystem

• Many of the organisms are occupy different places in the ecosystem

Trophic Categories

• The word “trophic” refers to food or feeding

• An animals trophic level refers to where on the food web an animal resides

Trophic Categories

• There are three main categories of organisms– Producers– Consumers– Detritus Feeders and

Decomposers

Trophic Levels• Organisms have different

ways to get food• Autotrophs produce their

own food– Plants, fungi and some

bacteria• Heterotrophs must

consume materials for food– Animals, some plants

bacteria

Producers

• Producers are organisms that capture energy from the sun or from chemical reactions to convert carbon dioxide to organic matter

• Most producers are green plants

• Producers are autotrophs

Producers

• Most plants create glucose from the sun in a process called Photosynthesis

• Plants are able to create all of the complex molecules in their body by absorbing CO2 and absorbing minerals from the soil

Consumers

• There are a very wide variety of organisms that are consumers– As small as a bacteria

and as large as a whale• All consumers are

heterotrophs

Consumers• Animals that feed directly

off of producers are called Primary Consumers or Herbivores – Sheep, elephants,

chipmunk, etc• Animals the feed on

primary consumers are called Secondary Consumers– Wolves, Seals, Spiders, etc

Predators, Parasites, Pathogens

• When one animal consumes another for food, it is a Predator & Prey relationship

• When an animal feeds on another, without killing it is a Parasite & Host relationship

Detritus Feeders and Decomposers

• Dead plant material, fecal wastes and dead animal bodies make up a large amount of energy

• That energy can be used by Detritus Feeders

Detritus Feeders and Decomposers

• Decomposers are a particularly important group of detritus feeders

• Decomposers are animals that “rot” dead organic matter– Bacteria and fungi make

up this group

Trophic Relationships

• All food levels on the trophic levels are interconnected

• This creates an interconnected chart that shows where energy goes, called a Food Web

• The different levels in the food web are called Trophic Levels

Trophic Relationships• In a food web there are

normally no more than three or four levels

• This is because there are different levels in biomass

• Biomass is a measurement of the weight of all the organisms at a particular step in the food web

Trophic Relationships• The amount of biomass can

often be represented by a trophic pyramid

• This is a visual representation of the amount of biomass in a system

• Only 10% of the biomass (or energy) in a level of the biomass pyramid is transferred to the next level

Trophic Pyramid