Lecture 17- Food Webs I Flashcards
What is a food web?
Collection of species present in a given space and time that are connected to each other through trophic interactions
Food webs are connected through _______
Connected through food and energy
A food web includes ____ and ____ interactions
- Direct
- Indirect
What is a food chain?
A simpler view that follows one pathway of energy
What is food web structure?
The number and types of species within the food web
What is the functional group?
Species with the same predator, food, role and fill the same ecological food niche
What is food web function?
The ways in which species interact with each other
Functioning describes ______
The transfer of energy through the structure of the web
What is a trophic level?
Position in the food chain
Trophic levels are determined by _______
The number of energy transfer steps to that level
What are the 4 first trophic levels?
- Primary producer
- Primary consumer
- Secondary consumer
- Tertiary consumer
What makes primary producers special?
They make food through a chemical pathway not through the consumption of another organism
What are the two types of primary consumers?
- Plants = photosynthesis
- Chemoautotrophs = create energy by breaking down other organic compounds
Have _____ chains in the north because ______
- Short
- Not as many species present
What is the definition of an ecosystem?
Interactions between organisms and their environments as an integrated system
What two components influence ecosystems?
- Biotic (plants, herbivores, predators)
- Abiotic (climate, water, precipitation, sunlight)
At each stage of a food chain ______ is lost
Energy
What limits the number of trophic levels you can have?
The loss of energy at each level
The one that eats the ______ gets the most energy
Primary producer
What are the two types of pathways?
- Grazing pathway
- Detrital pathway
What is the difference between a grazing pathway and a detrital pathway?
- Grazing = based on living plant material
- Detrital = based on the breakdown of dead or decomposing organic matter
Who is the primary producer in the grazing pathway?
The primary producers are the ones producing sugars and other things from a chemical pathway then its eaten by a primary consumer
Who is the primary producer in the detrital pathway?
Its the dead stuff and the primary consumer eats it
How can the grazing and the detrital pathway be connected?
