the foundation of all life is the cell.

They're incredibly complicated molecular factories and cellular biology studies the

structure and functions of the many different things inside a cell. Cells were evolving

for over 3 billion years until multicellular animals appeared. That's over two thirds

of the age of the Earth! So no wonder they are so complicated.

Cells are the smallest things that we think can be counted as life. Unfortunately there

isn't a good definition of life that everyone agrees on. For example, viruses, evolve and

replicate but they need other life to do so. Are they alive? Sort of but not really.

Molecular Biology looks into the insides of cells and studies how the different systems

work with each other on a molecular basis. It looks at DNA, RNA, amino acids and the

creation of proteins, how they interact with each other and what affects these interactions.

This is related to structural biology which looks at the shape of biological molecules

like amino acids, nucleic acids, and enzymes; why they have those structures and how differences

in their structure affects how they work.

Biochemistry goes one step even deeper and looks at how these biological molecules interact

with each other on a chemical level. Life is essentially a load of complex chemical

reactions and biochemistry studies the underlying chemical signals and reactions of life.

The molecules of life are too small to see with optical microscopes and so many techniques

in physics like x-ray crystallography, or cryo-electron microscopy are used to see the

structure of biomolecules. As well as tools for studying life, biophysics and quantum

biology also look at the physics that underpins biological processes, seeking to explain how

things work on a physical level.

Your DNA holds the blueprint of who you are and genetics is the study of how this information

is expressed to create all of the different forms of life through genes, and how this

information is passed on from one generation to the next.

Population genetics looks at the genetic differences within a species and how species differ from

one another.

The DNA code of an organism is huge and so we need computers to find patterns in the

data. Bioinformatics is the subject that uses computer programming to analyse and interpret

biological data in genetics, and also many other fields. Wherever the amount of data

is too large to analyse with previous statistical methods.

Biomathematics uses the tools of mathematics to build models of biological processes and

is used in many different areas from genetics to biotechnology to studying ecosystems.

You started off as a single cell, how that cell divided and grew into you is studied

by developmental biology. An interesting area in developmental biology is the growth and

differentiation of stem cells into the different cells in your body.

Anatomy looks at the the structure and organisation at the scale of entire organisms. It includes

both plants and animals and seeks to label all of the different components that make

up an organism.

Biomechanics looks at how parts of the body are designed for movement. The most obvious

is the articulation of our limbs, but it also includes the flow of fluids or the mechanical

properties of bones or tissues like the valves in our heart. At the microscopic level it

also looks at the strength or flexibility of cells or parts of cells.

While anatomy studies what organisms are made of, Physiology studies how these parts work

and interact with each other. It seeks to understand how all of the different components

in an organism work together to keep it functioning normally.

Immunology studies our immune system, how it protects us from infection in a multitude

of ways. It also investigates the many different ways our immune system can go wrong: allergies,

autoimmunity where your immune system attacks your own body, to wider conditions like cancer

and many other illnesses.

The increased lifespan of humans has been helped significantly by biomedical research:

trying to find ways to tackle the causes of illness and death. This spans many areas from

basic research, to developing new medical devices and new ways of finding and diagnosing

illnesses. Or developing new drugs through clinical trials in the pharmaceutical industry.

Bioengineering takes the principles of engineering and the knowledge of biological systems and

mashes them together to solve real world problems. This can be used to make devices to help in

medicine like artificial organs which called biomedical engineering.

And it can be used to create biotechnology like genetic engineering where the genetic

code of organisms is modified to tackle diseases or for example to make crops that are resistant

to challenging growing conditions.

Synthetic biology is another branch of bioengineering where scientists can make organisms that don't

occur in nature by making new sequences of DNA from scratch. Or re-designing existing

systems like genetically engineering e. coli to perform useful tasks like making drugs

or targeted delivery of drugs in the body.

It is worth pointing out that all of the subjects on this map are very interrelated. Most of

them draw upon many of the other areas in their research. A good example is neuroscience

the study of the nervous system and especially the brain. It involves the anatomy of the

brain, the physiology of neurons as well as molecular biology and biochemistry inside

the brain. So in Biology, as with most of science, there is a lot of cross pollination

between fields.

Pharmacology studies the effects drugs have in the body. It looks at many aspects of drugs,

how to make them, what to make them from and their effect in different biological systems.

Pharmacology is related pharmacy which is the science of preparing and dispensing drugs.

Pathology is the study of the causes and effects of diseases, and the diagnosis of disease

through taking samples from the body like blood or tissue. It also looks at how cells

adapt to injury, the healing of wounds, inflammation, or abnormal growth of new cells like with

cancer. It is also used to investigate how people have died using post mortem examinations.

Epidemiology looks at health and disease in whole populations and looks at the patterns

of disease, how it is transmitted and the effects on the overall health of a population.

Diseases are monitored all the time and if there is an outbreak epidemiologists swoop

in to work out how it is spreading to try mitigate the damage.

Taking a wider view, biology includes the study of the entire natural world. Looking

at the deep past we get Palaeontology the study of prehistoric life, looking at fossils

to work out what ancient creatures looked liked and how they evolved. It is closely

related to evolutionary biology which looks at how all of the life on Earth originated

from a single common ancestor and studies how evolution led to the wide diversity of

life on Earth.

The many plants and animals that live on the Earth today fall under the study of zoology,

marine biology and botany. These look at animals, plants and fungi, their development, behaviour,

physiology and how to classify all of the different species.

Ecology looks at how whole groups of animals and plants interact with each other in an

environment: how animals compete or cooperate with each other, and how many different kinds

of plants and animals inhabit the same environment.

This is closely related to environmental biology which looks at how eco-systems can be thrown

off balance by humans through pollution, agriculture or our fossil fuel emissions causing changes

to environments and the climate.

So far, the only life we have seen in the Universe exists on Earth, but are we the only

planet in the Universe with life on it? Or are there other planets out there with their

own strange forms of life? Astrobiology is our attempt to answer this question, to work

out how life may arise from chemical reactions and to probe distant planets and moons for

signs of life.

If there is one word that describes biology, it is complexity. There is a huge amount we

still don't understand about how life works, how it started and how it ended up with intelligent

apes like us who are able to look back and try and work it all out. I feel like we'll

be making new biological discoveries for many many years to come.

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