|
|
Branches of Science
There are several ways of broadly categorizing the sciences, e.g.
Pure science is systematic study of natural or physical phenomena
by observation and experiment, critical testing and review,
and ordering by general principles.
Applied science is the search for practical uses of scientific
knowledge; technology is the application of applied science.
Exact sciences are those which typically require precise measurements,
such as physics, and to a lesser degree, chemistry.
Descriptive sciences are those which are more oriented towards
classification and description, such as biology and paleontology.
The pure natural sciences are typically divided into
the physical sciences and the biological sciences,
both of which can be subdivided.
The major physical sciences are physics, astronomy, chemistry,
and geology;
the main biological sciences are botany and zoology.
The sciences aren't distinct and independent from each other,
but rather, there are are interconnections and cross-fertilisations.
These interrelationships are often responsible for much of the
progress today in several specialized fields of research,
such as molecular biology and genetics.
Several interdisciplinary sciences, such as biochemistry,
have been created as a result..
Advances can be the result of research by teams of specialists
representing different sciences, both pure and applied.
Economics is a social science that studies the production, distribution and consumption of goods and services. Simply put, economics is the science of man's resources, or wealth. Economists study how resources are produced and how they move around the world and within societies and markets, and how all of the different elements involved in resource allocation, such as commerce, finance, human labor, population, politics, the preservation and ownership of natural resources, etc., -- even weather -- interact to distribute wealth.
is the science or study of the thought processes and behavior of humans
and other animals in their interaction with their environment.
Psychology is the science of human behavior, the mind, and mental
processes in humans and animals as they interact with each other and
the environment. As a practice, psychologists focus on diagnosing,
assessing, and delivering preventive and therapeutic services directly
to individuals.
The science and study of life,
from the tiniest microscopic organisms to the largest whales in the sea.
Biology studies how living things grow, feed, move, reproduce,
and evolve over long periods of time.
It covers an enormous range of topics and deals with millions of
species of animals, plants, and other organisms.
To cope with this,
biology is divided into several specialised branches such as
anatomy (the structure of living things),
and physiology (the way animals and plants function).
Biology is useful to other sciences and professions that deal with life,
such as agriculture, forestry, and medicine.
Because there is such a huge variety of living things on the earth,
the science of biology has many different branches and areas of study.
Depending on their discipline, biologists usually research one or more
of the following categories:
Microbiology, a study dealing with the structure and existence of microorganisms,
which are tiny life forms such as a bacteria or a virus;
Zoology, which is the study of animal life;
Botany, which is focused on plant life;
And physical anthropology, where scientists study human life,
such as our existence and how we interact with other life forms.
Biologists also use other sciences to research life.
Without chemistry and physics, much of the knowledge we have gathered about
life would have been impossible to collect.
is the scientific study of life-forms existing in former geological
time periods.
When living things die they are sometimes buried in a layer of mud.
After millions of years the mud turns into solid rock and the remains
are preserved as fossils.
The layers of rock can be dated,
and so we know the age of the fossils in that layer.
Paleontologists have discovered much about life that existed millions
of years ago, by studying fossils.
Especially interesting are the fossils of dinosaurs,
some of which were very large indeed.
Paleontologists know what they looked like and what they ate.
Physical Sciences
is the scientific study of objects in space:
stars, planets, galaxies etc.
Astronomy is the science dealing with all the celestial objects in
the universe, including the planets and their satellites
(e.g. our Earth and the moon), comets and meteors,
the stars (including our sun), and interstellar matter,
the star systems known as galaxies, and clusters of galaxies.
Astronomers use telescopes (optical, radio, and others)
to study stars, planets, and galaxies.
Spacecraft carry telescopes and other astronomical instruments above
the Earth's atmosphere, and to other planets in our solar system.
Radio Astronomy
Radio Astronomy is the study of the Universe and astrophysical phenomena,
by examining their emission of electromagnetic radiation in the radio
portion of the spectrum.
Radio astronomy has greatly improved our understanding of the evolution of stars,
the structure of galaxies, and the origin of the universe.
Questions concerning the nature of the Universe as a whole were until recently,
the province of philosophy and superstition only.
There was no way to examine the fabric of the heavens to see what it was made of
- until the invention of spectroscopy and the construction of powerful telescopes
in the past century. The data collected have been analysed with sophisticated
mathematical techniques, and models have been developed which help us to
understand how this Universe may have come to be how it is.
Cosmology draws on the physical sciences - especially mathematics, physics, and astronomy.
is the study of the composition of substances and the changes that they
undergo.
In particular, chemistry is the study of elements
(substances containing only one kind of atom)
and the compounds (substances containing combined elements) they form.
Chemists work with reactions between substances to create plastics,
medicines, dyes, and many other materials useful in our modern world.
They study what substances are made of,
and how they can be altered or combined to create new materials.
92 elements occur in nature,
and another 17 have been created in nuclear laboratories.
Several million compounds have been synthesised by chemists.
There are two main divisions, organic and inorganic.
Organic chemistry originated with the isolation of medical compounds
from animals and plants. It has expanded to include the reactions of
carbon based compounds (which are 100 times more numerous than non-carbon based compounds)
and the study of molecules.
Inorganic chemistry studies the preparation, properties, and reactions of all
chemical elements and compounds except those that are carbon based.
is the science of matter and energy, including
light, sound, electricity, magnetism, radiation, and motion.
Physics was once called natural philosophy,
since it was "thoughts about the natural world".
Physicists work with a mixture of theory and experiment.
They perform experiments and try to construct theories to explain their
results.
These theories should make predictions which can be tested by new
experiments.
Those theories which have stood the test of time and have been
especially useful are called the laws of physics.
- Nuclear physics
-
studies atomic particles and the energy they contain - which has led
to the development of nuclear energy and weapons in the first half of
the twentieth century.
One of the main quests of science throughout the ages has been to
discover what matter is made of - and what holds it together.
All matter is made out of many tiny particles called atoms.
The study of how these atoms interact is called Chemistry.
Modern physics has discovered how atoms are made up of smaller
particles and how these particles interact to build atoms into
molecules and larger objects of matter.
- Light and Electromagnetism
-
Light is one of the most familiar things in our lives.
We see because we have organs (our eyes) that sense the intensity
(brightness) and wavelength (color) of light. We experience light in
a variety of other ways as well. For example, we sense radiant heat
when our skin is near a warm object.
This is due to our skin's reaction to infrared radiation.
We learn almost all of what we know about the world around us from the
interaction of the objects in the world with electromagnetic radiation.
Often, the word 'light' is used a little more broadly,
to include electromagnetic radiation that is just outside the range we can see,
in the ultraviolet and infrared.
- "the queen of the sciences" -
deals with abstractions rather than observables,
e.g. numbers, shapes, logic,
size, structure, order, and other relationships among quantities.
Some of the major branches are:
- Arithmetic concerns addition, subtraction, multiplication, and division of numbers.
- Algebra is a symbolic language in which problems can be solved using symbols to stand for varying or unknown quantities.
- Geometry is the study of shapes and angles, and is useful in carpentry, architecture, and many other fields.
One of the commonest applications of mathematics to science is the use
of equations to fit observed data, e.g. as in a graph of one quantity
against another, such as temperature against time, for a cooling body.
As used originally by the ancient Greeks,
philosophy meant the pursuit of knowledge
for its own sake.
Western philosophy is generally considered to have begun in ancient Greece
as speculation about the underlying nature of the physical world.
Philosophy comprised all areas of speculative thought and included
the arts and sciences.
The philosophy of science
seeks to clarify the objectives and means used by scientists,
and what is the reliability of scientific theories.
|
|