Saprotrophs
(forgot to add this in earlier :P )
A
Saprotroph (or Saprobe) is an organism that gets its energy from non-living
organic matter. This may be decaying pieces of plants or animals. This means
that saprobes are heterotrophs. They are consumers in the food chain. Many
fungi are saprobes. This is also true for many bacteria and protozoa. To put it
simply, most dead organic matter is eventually broken down and used by bacteria
and fungi. It is a heterotroph because it likes to search for its own food and
is therefore a consumer.
TROPHIC
LEVELS
The
trophic level of an organism is the position it occupies in a food chain. A
food chain represents a succession of organisms that eat another organism and
are, in turn, eaten themselves. The number of steps an organism is from the
start of the chain is a measure of its trophic level. Food chains start at
trophic level 1 with primary producers such as plants, move to herbivores at
level 2, predators at level 3 and typically finish with carnivores or apex predators
(predators with no predators of their own) at level 4 or 5. The path along the
chain can form either a one-way flow, or a food "web." Ecological
communities with higher biodiversity form more complex trophic paths.
EXAMPLES
of BIOTIC and ABIOTIC factors:
Abiotic
factors: soil, relative humidity, moisture, ambient temperature, sunlight,
nutrients, oxygen
Biotic
factors: competitors, predators and parasites
SYMBIOTIC
relationships
Commensalism: In ecology, commensalism is a class of
relationship between two organisms where one-organism benefits but the other is
neutral (there is no harm or benefit).
Mutualism:
Mutualism is the way two organisms of different species biologically interact
in a relationship in which each individual derives a fitness benefit.
Parasitism:
Parasitism is a type of non-mutual relationship between organisms of different
species where one organism, the parasite, benefits at the expense of the other,
the host.