Living Environment Translated English 2014 | Page 33

o Tertiary consumers are carnivores that eat other
secondary consumers.
 The amount of available energy decreases from the base to
the top of the energy pyramid.
 Generalists are consumers that have a varying diet.
 Specialists are consumers that eat only one specific
organism or feeds on a very small number of organisms.
 Symbiosis is any close relationship between species.
o Mutualism is a symbiotic relationship in which both
species benefit from each other.
o Commensalism is a symbiotic relationship in which
one organism benefits and the other organism is not
affected.
o Parasitism is a symbiotic relationship in which one
organism benefits but the other organism is harmed.
 An organism’s niche describes the ways in which the
organism obtains food, avoids danger, and finds shelter.
18. Abiotic factors are nonliving, physical features of the
environment
 Examples : air, water, soil, sunlight, temperature, and
climate
 The air that surrounds the Earth is called the atmosphere. It
contains 78% nitrogen, 21% oxygen, 0.03 % carbon dioxide
and other trace materials.
 Water is essential to life on earth. Many important life
processes can only take place in the presence of water.
 Soil is a mixture of mineral and rock particles, the remains
of dead organisms, water and air. It is the topmost layer of
the Earth’s crust and it supports plant growth.
 Climate refers to an area’s average weather conditions over
time, including temperature, rainfall and other
precipitation, and wind.