First 265 words of the document:
Biomass in food chains:
Radiation from the sun is the source of energy for most communities of
living organisms. Green plants capture a small part of the solar energy
which reaches them. This energy is stored in the substances which make
up the cells of the plants.
The mass of living material (biomass) at each stage in a food chain is less
than it was at the previous stage. The biomass at each stage can be
drawn to scale and shown as a pyramid of biomass.
At each stage in a food chain, less material and less energy are contained
in the biomass of the organisms. This means that the efficiency of food
production can be improved by reducing the number of stages in food
The efficiency of food production can also be improved by restricting
energy loss from food animals by limiting their movement and by
controlling the temperature of their surroundings.
The amounts of material and energy contained in the biomass of
organisms is reduced at each successive stage in a food chain because:
1. Some materials and energy are always lost in the organisms' waste
2. Respiration supplies all the energy needs for living processes, including
movement. Much of this energy is eventually lost as heat to the
3. These losses are especially large in mammals and birds whose bodies
must be kept at a constant temperature which is usually higher than that
of their surroundings.