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Biology: Biology is the branch of science dealing with the study of life. It is concerned with the characteristics, classification,
and behaviors of organisms, how species come into existence, and the interactions they have with each other and with the
environment. Biology encompasses a broad spectrum of academic fields that are often viewed as independent disciplines.
However, together they address phenomena related to living organisms (biological phenomena) over a wide range of scales,
from biochemistry to ecology.
Biology studies the variety of life (clockwise from top-left) E. coli, tree fern, gazelle, Goliath beetleAt the organism level, biology has
explained phenomena such as birth, growth, aging, death and decay of living organisms, similarities between offspring and their
parents (heredity) and flowering of plants which have puzzled humanity throughout history. Other phenomena, such as lactation,
metamorphosis, egg-hatching, healing, and tropism have been addressed. On a wider scale of time and space, biologists have
studied domestication of animals and plants, the wide variety of living organisms (biodiversity), changes in living organisms over
time (evolution), extinction, speciation, social behaviour among animals, etc.
While botany encompasses the study of plants, zoology is the branch of science that is concerned about the study of animals and
anthropology is the branch of biology to study human beings. However, at the molecular scale, life is studied in the disciplines of
molecular biology, biochemistry, and molecular genetics. At the next level, that of the cell, it is studied in cell biology. At the
multicellular scale, it is examined in physiology, anatomy, and histology. Developmental biology studies life at the level of an
individual organism's development or ontogeny. Moving up the scale towards more than one organism, genetics considers how
heredity works between parent and offspring. Ethology considers the behaviour of groups of organisms. Population genetics
looks at the level of an entire population, and systematics considers the multi-species scale of lineages. Interdependent
populations and their habitats are examined in ecology and evolutionary biology. A speculative new field is astrobiology (or
xenobiology), which examines the possibility of life beyond the Earth.
It help us to know a little about what is the origin of life in our planet. May be in simple way we can refer to it:
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Scope:
As all we know the science of Biology has many different sections, from those we are interested on ECOLOGY. This is what
can help us more in this direction that we want to act. We take a look at main points of this science.
Ecology:
Ecology is usually considered a branch of biology, the general science that studies living organisms. Organisms can be
studied at many different levels, from proteins and nucleic acids (in biochemistry and molecular biology), to cells (in cellular
biology), to individuals (in botany, zoology, and other similar disciplines), and finally at the level of populations, communities,
and ecosystems, to the biosphere as a whole; these latter strata are the primary subjects of ecological inquiries. Ecology is a
multi-disciplinary science. Because of its focus on the higher levels of the organization of life on earth and on the
interrelations between organisms and their environment, ecology draws heavily on many other branches of science,
especially geology and geography, meteorology, pedology, chemistry, and physics. Thus, ecology is said to be a holistic
science, one that over-arches older disciplines such as biology which in this view become sub-disciplines contributing to
ecological knowledge.
Agriculture, fisheries, forestry, medicine and urban development are among human activities that would fall within Krebbs'
(1972: 4) explanation of his definition of ecology: "where organisms are found, how many occur there, and why".
As a scientific discipline, ecology does not dictate what is "right" or "wrong". However, ecological knowledge such as the
quantification of biodiversity and population dynamics have provided a scientific basis for expressing the goals of
environmentalism and evaluating its goals and policies. Additionally, a holistic view of nature is stressed in both ecology and
environmentalism.
Consider the ways an ecologist might approach studying the life of honeybees:
the behavioral relationship between individuals of a species is behavorial ecology — for example, the study of the queen bee,
and how she relates to the worker bees and the drones.
The organized activity of a species is community ecology; for example, the activity of bees assures the pollination of flowering
plants. Bee hives additionally produce honey which is consumed by still other species, such as bears.
The relationship between the environment and a species is environmental ecology — for example, the consequences of
environmental change on bee activity. Bees may die out due to environmental changes (see pollinator decline). The
environment simultaneously affects and is a consequence of this activity and is thus intertwined with the survival of the
species.
In biology and ecology, an organism (in Greek organon = instrument) is a living complex adaptive system of organs that
influence each other in such a way that they function as a more or less stable whole. An organism is in a non-equilibrium
thermodynamic state, maintaining a homeostatic internal environment, and a continuous input of energy is required to
maintain this state.
The origin of life and the relationships between its major lineages are controversial. Two main grades may be distinguished,
the prokaryotes and eukaryotes. The prokaryotes are generally considered to represent two separate domains, called the
Bacteria and Archaea, which are not closer to one another than to the eukaryotes. The gap between prokaryotes and
eukaryotes is widely considered a major missing link in evolutionary history. Two eukaryotic organelles, namely mitochondria
and chloroplasts, are generally considered to be derived from endosymbiotic bacteria.
The phrase complex organism describes any organism with more than one cell.
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