B2 - Feeding Relationships Flashcards
Define the terms producer, consumer, herbivore, carnivore and omnivore.
Producer : organisms that make their own food e.g plants and algae
Consumer : organisms that eat other organisms
Herbivore : animals that eat plants. They are also primary consumers and the second link in the food chain.
Carnivore : animals that eat other animals. Also called secondary consumers and are the third link in the chain. Top carnivores eat other carnivores.
Omnivore : animals that eat both animals and plants ( therefore they are primary and secondary consumers )
What are detrital food chains? What two other feeding types do they involve?
These food chains start with dead material or waste.
They involve :
- detritivores are organism that eat dead material such as dead leaves
- decomposers decay the bodies of other organisms, but do not eat them
How do you plot a pyramid of numbers?
• The organisms are plotted as separate blocks.
• The size of each block is related to the number of
organisms.
• The producer always goes at the base, with each
successive link above it.
How do you plot a pyramid of biomass?
- multiply the number of organisms at each link in the food chain by the dry mass of one organism
- This gives the biomass for that link in the chain
- This can now be plotted as a pyramid of biomass.
What are the limitations of a food pyramid?
Many organisms eat lots of things, so could be at different levels. Also, calculating dry mass involves killing and drying organisms.
How does energy enter a food chain and how does it leave? Where is it used?
Energy enters food chains and webs when plants capture sunlight energy.
Leaves through :
- respiration for movement and heat
- undigested food is ejected
- excretory products like sweat and urine are excreted
How do you calculate the efficiency of energy transfer?
Energy built into organism
Efficiency = ____________________________________ x 100
Energy available
