Biology is the study of life. Alongside physics and chemistry, biology
is one of the largest and most important branches of science. At the
highest level, biology is broken down based on the type of organism
being studied: zoology, the study of animals; botany, of plants; and
microbiology, of microorganisms. Each field has contributed to mankind
or the Earth’s well-being in numerous ways. Most prominently: botany, to
agriculture; zoology, to livestock and protection of ecologies; and
microbiology, to the study of disease and ecosystems in general.
Besides
classifications based on the category of organism being studied,
biology contains many other specialized sub-disciplines, which may focus
on just one category of organism or address organisms from different
categories. This includes biochemistry, the interface between biology
and chemistry; molecular biology, which looks at life on the molecular
level; cellular biology, which studies different types of cells and how
they work; physiology, which looks at organisms at the level of tissue
and organs; ecology, which studies the interactions between organisms
themselves; ethology, which studies the behavior of animals, especially
complex animals; and genetics, overlapping with molecular biology, which
studies the code of life, DNA.
The foundations of modern biology
include four components: cell theory; that life is made of fundamental
units called cells; evolution, that life is not deliberately designed by
rather evolves incrementally through random mutations and natural
selection; gene theory, that tiny molecular sequences of DNA dictate the
entire structure of an organism and are passed from parents to
offspring; and homeostasis, that each organism’s body includes a complex
suite of processes designed to preserve its biochemistry from the
entropic effects of the external environment.
The basic picture
in biology has stayed roughly the same since DNA was first imaged using
x-ray crystallography in the 1950s, although there are constant
refinements to the details, and life is so complex that it could be
centuries or even millennia before we begin to understand it in its
entirety. But it should be made clear that we are moving towards
complete understanding: life, while complex, consists of a finite amount
of complexity that only appreciably increases on relatively long
timescales of hundreds of thousands or millions of years. Evolution,
while creative, operates slowly.
In recent years, much excitement
in biology has centered on the sequencing of genomes and their
comparison, called genomics, and the creation of life with
custom-written DNA programming, called synthetic biology. These fields
are sure to continue grabbing the headlines in the near future.