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Biomass loss from food chains
Chickens can use 80% of the biomass from the maize seeds they eat for respiration and growth. What happens to the remaining 20% of the biomass in the maize seeds?
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Marking points
- 1 States that the remaining biomass is lost by egestion/in faeces.
Full-mark answer
It is egested from the chicken in the faeces.
Why this answer loses marks
It is used in respiration and lost as heat.
The prompt already assigns respiration to the usable fraction; the remainder is credited as biomass lost through egestion or faeces.