Explain how respiration, heat, egestion, excretion and uneaten biomass reduce energy availability, then calculate or compare transfer efficiency in IB Biology SL C4.2.12.
Food chains combine to form food webs in an ecosystem.
The efficiency of energy transfer along the various food chains in a food web varies. Suggest reasons for the differences.
a. energy is lost between trophic levels as heat/metabolism/10\% (or less) is transferred (accept converse);
b. length of food chains varies / number of trophic levels in the food chains vary;
c. some animals / herbivores may be able to digest (more) plant material/ cellulose/ parts of their food such as skin or bones than other animals;
d. some animals are different in size / are more active;
e. use more energy (to keep warm or cool) than others/are warm or cold blooded;
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