Ecology Flashcards
The word ‘___ was first used by Ernest Haeckel in 1869. He describe __ as the
scientific study of the interactions between organisms and their environment. The word is
derived from the Greek oikos, meaning ‘home’. __ might therefore be thought of as the
study of the ‘home life’ of living organisms
Ecology
In 1972, he define ecology as the scientific study of interactions that determine the
distribution and abundance of organisms. Notice that it’s do not use the word environment. It
is necessary to define the word
Krebs
Ecologist have identified four fundamental levels of the organization to study the interactions
between organisms and their environment.
1.Individual
2.Population
3.communities
4.Ecosystem
a single species, at the level of organisms, ecology deals with
how individual organisms are affected by (and how they affect) their environment.
Individual (organisms)
A group of individual with the same species in a given area. Populations of
different species in an area do not function independently of each other. They interact with each other. Hence, the next, more complex level of organization is.
Population
made up of interacting populations of different species within some
defined geographical area.
Communities
the interacting system made up of all the living and non-living components
in a physically defined space. Because an ecosystem is a system, it has boundaries.
Ecosystem
the highest level of organization, it is an ultimate ecosystem. It includes all
ecosystems present on the earth ̶ environment on a planetary scale.
Biosphere
is a basic functional unit of ecology comprising of all organisms in a
particular place interacting with one another with their physical environment and interconnected
by an ongoing flow of energy and a cycling of nutrients.
ecosystem
Two basic components of structure of an ecosystem
- Biotic components
- Abiotic components
living organisms in an ecosystem can be classified as either
producers or consumers, depending on how they get their food (PRODUCERS, CONSUMER, DECOMPOSERS)
Biotic Components
all the physical and chemical factors that influence living
organisms, like air, water, soil, rocks etc. Thus, it is an assemblage of organic and inorganic
substances present in an ecosystem. Also various climatic factors are also part of this.
Abiotic Components
is a fundamental process which occurs in all ecosystems. Energy is defined as
the capacity of work. It is the basic force responsible for all metabolic activities. The flow or movement of energy through a series of organisms in an ecosystem is called energy flow. The
energy flows from producer to top consumers in unidirectional form.
Energy flow
The transfer of food energy from producers through a series of organisms that consume and are
consumed
FOOD CHAIN
Food chains usually consist of producers :
1.primary consumers
2.secondary consumers
3.tertiary
consumers
4.decomposers.
