Biological activity requires utilization
of energy, which comes from the sun.
Solar energy is converted into chemical
energy by the process of photosynthesis.
This chemical energy is then transformed
into mechanical and heat forms during
metabolic activities. The flow of energy
in the biological world takes place from
the sun to the plants and then to the
heterotrophic organisms (animals,
humans, microorganism) and so on.
A few generalizations can be made in the
flow of energy and inorganic nutrients
through the ecosystem.
For most of the ecosystems the vital
source of energy is the sun.
The eventual outcome of energy in
ecosystems is for it to be lost as heat.
Through the food chain energy and
nutrients are passed from one organism
The decomposers remove the last energy
from the remains of organisms.
There is cycling of inorganic nutrients
but energy does not recycle