Food Chains + Biomass Flashcards
What is a food chain?
A diagram that describes a feeding relationship between organisms.
What do arrows in the food chain represent?
Direction of energy transfer.
What are food webs?
A map of many food chains linked closely together. Show the feeding relationships between multiple organisms.
What is a trophic level?
Each stage within a food chain, such as producer, consumer etc
What is a producer (autotroph)?
A photosynthetic organism that manufactures organic compounds using light energy, CO2, water and mineral ions.
What is a consumer (heterotroph)?
What do primary consumers and secondary consumers eat?
Organisms that gain their energy by eating other organisms. Primary consumers eat producers and secondary consumers eat primary consumers etc.
What are saprobionts?
Bacteria and fungi that break down decaying complex organic substances into simple ones.
What can the minerals released by saprobiontic decomposition be used for?
Nutrient recycling in plants.
What is biomass?
The total mass of living materials found in a specific area (not including their water content)
What is needed to calculate the biomass of a small area?
A small, but representative sample of the area.
Give the units for biomass.
Dry mass per given time
(g m-2)
How is energy lost by consumers during respiration?
Energy is lost as heat.
Give 4 ways that energy is lost from consumers.
Energy is lost when not all of the organism is eaten (such as bones)
Energy is lost in excretory materials
Energy is lost in material that cant be digested
Energy is lost in heat during respiration
Give 4 ways energy is lost by producers.
The suns energy is reflected back to the atmosphere
Not all wavelengths of light can be absorbed by the photosynthetic pigments present
Light may not fall on a chlorophyll molecule
There may be factors that limit rate of photosynthesis.
