trophic levels in an ecosystem

what does a food chain show

A description of the feeding relationships between organisms and the resultant states of biomass transfer

what are Trophic levels

stages in a food chain

how are trophies levels represented

represented by numbers, starting from 1 after 1, trophic levels are numbered according to far along the organism is in the food chain

trophic level 1

plants and algae which make their own food (through photosynthesis) called producers

Trophic level 2

herbivores that feed on the producers- called primary consumers

Trophic level 3

carnivores that consume herbivores- called secondary consumers

Trophic level 4

Composed of carnivores that eat other carnivores- called tertiary consumer

Apex predator

carnivore that occupies the highest trophic level no natural predators.

how do decomposers break down dead matter

release enzymes which catalyse breakdown of dead material into smaller molecules soluble small food molecules then diffuse into microorganisms

Biomass

The dry mass of all living organisms in an area.

why is dry mass used for biomass

because the wet mass varies as the volume of water in organism varies

how do you calculate the efficiency of biomass transfer

efficiency= (energy transferred/ total energy available) x 100

what Percentage of the incident energy from light for photosynthesis do producers transfer

1%.

Percentage of biomass transferred between trophic levels

Approximately 10%

Reasons for biomass transfer inefficiency

egestion excretion respiration (Loss of co2 and water in which large amounts of glucose are used) production of inedible bones and shells

how does the affect of biomass transfer efficiency effect the number on trophic levels

Less efficient transfers=fewer trophic levels and fewer organisms in higher trophic levels.

what is biomass pyramid

pyramid showing the total dry mass of organisms at each trophic level.

what is a Pyramid of numbers

shows the number of organisms at each trophic level.

Reason for pyramid of numbers not being pyramid shaped

pyramid of numbers does not consider the size and mass of organisms