Nutrition and Energy Flow Feeding Relationships

Energy Anytime an organism eats, it’s doing two things: consuming matter obtaining energy

Energy Studying FEEDING RELATIONSHIPS and ENERGY FLOW helps one understand how an ecosystem functions

Energy In discussing the flow of energy, there are organisms that PRODUCE it and organisms that simply CONSUME it

Producers Producers don’t actually make the energy, but they change its form Convert solar energy into glucose and ATP What type of organisms are producers?

Plants (w/ some exceptions) Plants undergo PHOTOSYNTHESIS to convert solar energy into GLUCOSE. GLUCOSE is later broken down to form ATP. ATP = Adenosine Triphosphate ATP is the energy molecule used by cells.

Producers Producers are also called AUTOTROPHS Auto = self -troph = refers to nutrients

Consumers Some organisms do not have the ability to use the suns energy to produce carbon based molecules and must eat other organisms in order to do so. Consumers are called HETEROTROPHS Hetero = other, different -troph = refers to nutrients

Herbivores Heterotrophs that eat ONLY autotrophs are called HERBIVORES Herbi = from herba - grass -vore = from vorare, to devour

Heterotrophs that ONLY eat other heterotrophs are CARNIVORES Carne = meat, flesh

Omnivores Heterotrophs that eat BOTH autotrophs and other heterotrophs are OMNIVORES Omni = all

Heterotrophs that are opportunistic and do not kill for food Scavengers Heterotrophs that are opportunistic and do not kill for food

Decomposers Break down dead organisms into simpler molecules which are released back into the Earth.

Matter and Energy Flow When you eat, you consume matter which cycles through an ecosystem from autotrophs to heterotrophs You also capture some of the energy present in the food and some energy is lost as heat.

Models In order to study and understand the flow of matter and energy, scientists use different models.

Food Chain The simplest model is a FOOD CHAIN. It shows only one pathway that energy may be transferred. It moves from autotrophs to heterotrophs

Food Chain Arrows are used to show the direction of energy flow. If you are not sure, think of the arrows as meaning “...is eaten by...”

Construct a food chain... Create a food chain using the following organisms

grass > grasshopper > sparrow > gopher snake> coyote

Food Webs FOOD WEBS show all possible feeding relationships, i.e. every possible pathway for the transfer of matter and energy A food web shows many food chains

Food Web

Food Webs Food webs show ALTERNATIVE PATHWAYS - other possible pathways through which an organism can obtain energy

Alternative Pathways