Let’s Explore Stuff |

08May 2013

The 5 Greatest Astronomers Throughout History

Throughout history, there have been countless astronomers who have made an impact on man’s knowledge of the universe. While each small discovery certainly has scientific worth, there have also been several forward-thinking scientists who stand out as the greatest astronomers of all time. By boldly rethinking conventional beliefs about the nature of the universe, these 5 astronomers have truly revolutionized mankind’s knowledge of space and of the planet Earth.

Copernicus, Nicolaus (1473-1543)

Copernicus was a Polish astronomer who first theorized that the long-standing geocentric model of the universe was incorrect, and that the Earth and other celestial bodies instead moved around the Sun. His introduction to this idea, the Commentariolus, was his first heliocentric writing, and his book On the Revolutions expounded on these concepts. Although his work was very controversial at the time, Copernicus has since become one of the greatest astronomers in history because his revolutionary theories paved the way for modern astronomy.

Galileo, Galilei (1564-1642)

Not only is Galileo considered to be one of the greatest astronomers of all time, but he is also often referred to as “The Father of Modern Science”. He was the first person to methodically study space with a telescope, and his observations provided conclusive scientific evidence that the heliocentric model of the universe posited by Copernicus was indeed correct. He also discovered the phases of Venus, the moons of Jupiter, and the dark marks, which were later named sunspots, on the surface of the Sun.

Halley, Edmond (1656-1742)

English astronomer Edmond Halley is best known for being the first person to discover and calculate the orbit of a comet. His theory that comets’ orbits are periodic was proven when he correctly predicted that a comet observed in 1682 (later named Halley’s Comet) would again be seen in 76 years. Halley also personally catalogued the positions of nearly 350 stars (an extraordinary feat at the time), and introduced the notion of stellar proper motions, a theory stating that although stars seem to remain in a fixed position, they actually have a small, independent movement of their own.

Herschel, William (1738-1822)

Herschel’s journey towards becoming one of the greatest astronomers in history began with a love of building telescopes. He constructed over 400 telescopes during his lifetime, including the famous Herschelian telescope, an enormous reflecting telescope. Using his innovative designs, Herschel was able to discover Uranus, as well as two of the planet’s major moons, Oberon and Titania. He also discovered two of Saturn’s moons, and was the first person to observe that the solar system wasn’t stationary, but was in fact moving through the universe.

Hubble, Edwin (1889-1953)

Often said to be the “Father of Observational Cosmology”, Hubble was an American astronomer who was the first person to view distant space beyond Pluto, and in doing so changed the world’s view of the cosmos forever by discovering and classifying many galaxies that were unknown at the time. With the formulation of Hubble’s Law in 1929, he also proved that the universe was not in a fixed position but was actually expanding; a radical concept that eventually inspired the creation of the Big Bang Theory.

A great astronomer not only makes new discoveries, but also challenges conventional thought with groundbreaking ideas that further mankind’s knowledge of the universe. The crucial insights of these extraordinary scientists have solidified their position as 5 of the greatest astronomers in human history.

17Apr 2013

Let’s Explore Google Glass

Jason Carr ⋅ 1 Comment

Google Glass is thought to be the next great thing in augmented reality but most people are still not clear about how the new smart devices are going to work. The infograph below details how Google Glass is expected to work in a great way so I thought I’d share with you today. Based on the image below, there’s actually a small integrated projector that is recognized by the human eye without obscuring vision…cool. As an individual that wears glasses, I’m curious what Google is doing to accomodate those with prescription wear such as myself. The author of the infographic below has suggested that individual prisms for each user will need to be customized – something that may make the cost of the devices skyrocket. Time will tell. Either way, I am excited about the future of Google Glass and personally can’t wait to try them out. What are your thoughts on Google Glass? Are you planning on getting a pair when they’re available?

Infographic via: brille-kaufen.org

28Mar 2013

Awake While Asleep: Lucid Dreaming

Jason Carr ⋅ 8 Comments

Image Credit: webneel.com

For the typical dreamer, a dream is usually a phenomenon that’s only experienced in hindsight. We may be moved to wonderment by the memory of it, but oftentimes we’ve missed out on the actual moment of participation. What’s more, we may already have begun to alter many of the details due to foggy recollection. We’re thus already experiencing a translation of our dream by the time we awaken.

In order to catch the legitimate experience while it’s actually occurring we have to somehow become conscious and aware in the midst of a dream in progress. This is called lucid dreaming. It is possible, with practice and clear intentions, for us to literally be “awake” while sleeping. We can be as consciously aware inside of a dream as we are in waking life.

A lucid dream will be marked by a moment of recognition. In one way or another, you will find yourself saying, “I think I’m dreaming this right now!” What happens next will be crucial, because it’s very easy for us to slip out of this state of alertness and let our dreams move on without our conscious participation. A lot of literature about lucid dreaming advises us to try and find our hands at this point. This is one simple means of focusing and of holding on to the moment of awareness for as long as possible. Our bodies probably serve as the most trustworthy points of reference for us because we identify ourselves with them so much during our waking hours.

Unfortunately, this moment of lucidity within a dream can be experienced at random times; and many people never arrive at it. How then can we actively seek – or invite – lucid dreams? First we have to believe that such a thing as lucid dreaming is possible. If you look at your dreaming life as just another kind of awareness and experience – the other side of waking consciousness – then it will seem much more feasible for you to remain alert when you enter into this other state.

If you’re clear in your belief that lucid dreaming is a natural process, then you can train your mind to be alert to it with gentle reminders. Simply tell yourself, before going to sleep at night, that you will awaken inside your dreams. We usually don’t carry conscious suggestions with us into the dream state only because we so firmly believe that waking and dreaming are such distinctly different activities. Tell yourself that, although you are about to slip into another realm of consciousness, you will continue to be alert and responsive.

Nightly dream activity typically feels divorced from the rest of life, like a bizarre side-show. Lucid dreaming can teach us that we’re capable of many levels of awareness, and that each one offers valuable treasures of wisdom, knowledge and insight. We can learn how truly flexible consciousness is, and how many different environments it can operate in. Anyone who has been touched by the inexplicable wonder of a dream can learn to carry some of this magic back up into their waking lives. The daily world of ordinary consciousness may never look the same again.

11Mar 2013

Let’s Explore Quantum Computing

Jason Carr ⋅ 4 Comments

A quantum computer would be able to store more bits of information in its memory than there are particles in the universe. Image Credit: Alengo/iStockPhoto

It’s fairly easy to surmise how quantum computing will evolve in the future if/when it becomes a reality. Devices that are currently based around a system of electronic circuits would eventually die off. Quantum devices would ultimately become the new standard in computing. While Peter Shor’s research showed how quantum algorithms would speed up advanced calculations, they never really demonstrated why people would want to do this.

Today we have plenty of areas where quantum computing would certainly shine. Speed usually isn’t important when it comes to data storage and retrieval systems. Entertainment devices, however, are getting increasingly complex. This shouldn’t be taken as a suggestion that quantum computing would only be useful for a new generation of video game consoles, however.

Society would eventually start to merge all forms of media into one. Whether this would be the trigger to bring on the singularity is hard to say, but it’s easy to imagine that it would certainly usher in a very different form of art. Like the interactive media movement, quantum art would fundamentally change the way that people interact with the world.

Storage systems could still see a boost from the field of quantum computing as well. Electronic quantum holography also looks pretty promising. Holograms loaded with data could be projected onto a small mass. A piece of software could then reconstruct information from these holograms in the same way that software currently reconstructs data from magnetic or electrical impulses.

Some amount of energy would need to be expended to ensure that the holograms remain in a viable state. This shouldn’t be too much of a problem. Battery backup memory has worked that way for years. Even flash memory has to maintain a small amount of voltage to ensure that it works as desired. Electronic quantum holography could be viewed as the natural extension of these already proven examples of information technology.

Interestingly enough, no one has really been able to demonstrate the reason that quantum circuits would be superior to their regular electronic contemporaries. Most of what researchers believe is based wholly on assumptions/theory. While some people feel that quantum devices will never really replace microprocessors, it’s easy to imagine the microchip going the way of the vacuum tube. While transistors have almost completely replaced electronic valves, there remains few niche industries that continue to use them today.

On the totally other side of the spectrum, some people feel that quantum computers will someday be able to violate the basic theories of cognitive science. The idea of a self-aware machine has been bandied about for quite some time. When talking about the possibilities, it’s important to remember a few things. What currently defines a computer is at least in part based on the old Church-Turing thesis.

When this is violated, the whole idea of computational notions cease to be individual, autonomous units. Since quantum computers could solve equations that modern computers have found impossible, they force researchers to redefine the abstracts of efficient algorithms.

Superposition principles tell us that the bit is the smallest unit a machine can handle. A regular bit can only exhibit the features of one of two states. This is where the basic rules of binary math come from. Any single bit can be classified as 1 or 0. However, quantum computing defies these rules. By definition, a quantum computer is one that can handle bits assigned a third state. This state is somewhere between the two. Currently, computers can only tell if a circuit is switched on or not. A quantum computer would probably sense different voltages to ascribe values to some fraction of power. Some researchers use creative names like qubits to describe the components of quantum logic gates.

Quantum logic doesn’t even need to rely on electronics, however. Unconventional designs will probably evolve in the near future. Chemical computer systems, which are sometimes derisively referred to as gooware, would assign values to different chemical reactions. While it might seem weird to leave a tub of chemicals on a desk, practical designs might be closer to a dry cell battery. They could be quite small and portable.

Other logic systems have been proposed as well. Logic gates built around photons would allow nonlinear calculations. Photonic controlled gates would allow quantum computers to be built around electromagnetic models. Even with these types of advances however, future consumers would probably be more apt to buy something close to what they already know – at least in the early years of quantum computing. That makes photonic logic a good option for companies who want to pursue something they could actually market early on.

Reference:

Benningshof OW, Mohebbi HR, Taminiau IA, Miao GX, & Cory DG (2013). Superconducting microstrip resonator for pulsed ESR of thin films. Journal of magnetic resonance (San Diego, Calif. : 1997), 230C, 84-87 PMID: 23454577

Petersson KD, McFaul LW, Schroer MD, Jung M, Taylor JM, Houck AA, & Petta JR (2012). Circuit quantum electrodynamics with a spin qubit. Nature, 490 (7420), 380-3 PMID: 23075988

27Feb 2013

Let’s Explore Flywheel Energy Storage Devices

Jason Carr ⋅ 4 Comments

Credit: Flybrid Systems, L.P.

Flywheel energy storage devices could be looked at as a radical application of very traditional technology. They work by maintaining rotational energy by moving a flywheel. This same idea is used to keep a mechanical watch ticking.

A majority of modern FES devices use electricity to put the flywheel in motion, but some researchers are interested in the idea of using mechanical energy to start and stop the wheel. Modern devices stored in vacuum enclosures can spin at speeds exceeding 50,000 RPM. By using high strength carbon filaments that are suspended by magnetic bearings, FES installations can transfer energy in ways that conventional methods can’t.

Storing energy has always been a problem. Underground hydroelectric plants are sometimes used to store potential energy and flood the power grid with it during peak usage times. Chemical batteries are the storage solution that most people are familiar with. These are used in everything from automotive applications to TV remotes. However, neither of these options is ideal.

When people criticize solar and wind energy, they usually bring up the fact that neither technology works when weather conditions aren’t right. It’s hard to store solar or wind energy for use later. Flywheel energy storage systems would be perfect for these applications.

Flywheel Energy Storage System. Credit: Virginia Tech.

Some very ingenious people have brought this idea into the transportation industry. Using futuristic railroad vehicles, flywheel proponents have been able to build vehicles that can move up to fifty people 15 miles on one gallon of fuel. Self-propelled train cars can charge up their flywheels from an electrical supply provided at each station stop. The charging process would only take 30 seconds.

Credit: University of Texas

There are actually several niche industries where flywheels are already making a pretty big impact. Testing circuit breakers might sound like boring work, but its completely necessary in a society so reliant on electricity to stay connected. The amount of energy needed to fully trip a circuit breaker is immense, so it wouldn’t be possible to do this kind of job off grid power. Flywheels provide a ready source of stored power that doesn’t cause brownouts.

Amusement rides suffer from the same problem. Flywheels are starting to revolutionize the way that amusement parks store energy for things like roller coaster lifts. Even though this doesn’t sound like the most important field of research, it’s helping to cut down on how much energy these machines draw from the grid.

NASA has even gotten a good bit of publicity as a result of their G2 flywheel installation. They would certainly make good storage systems for orbital platforms. Future space colonies could use them to store power for peak usage times. That would allow people to continue to use appliances in space the same way they use them on terra firma.

Reference:

Zhang, C., & Tseng, K. (2007). A Novel Flywheel Energy Storage System With Partially-Self-Bearing Flywheel-Rotor IEEE Transactions on Energy Conversion, 22 (2), 477-487 DOI: 10.1109/TEC.2005.858088

MacIntosh BR, Rishaug P, & Svedahl K (2003). Assessment of peak power and short-term work capacity. European journal of applied physiology, 88 (6), 572-9 PMID: 12560957

08Feb 2013

What’s Killing Our Honey Bees – And What’s at Stake?

Jason Carr ⋅ 4 Comments

Along with other pollinators (which include hoverflies, butterflies and moths), honey bees perform a crucial role in the production of one-third of all the food we eat. Honey bees alone pollinate roughly fourteen billion dollars’ worth of food crops annually. They comprise a necessary part of the living ecosystem, and we would be hard-pressed to supply our world’s food needs without them.

Beginning around 2007, those who worked closely with these bees (including beekeepers and agricultural experts) began noticing troubling signs of de-population. Within that year, beekeepers in more than twenty states across the U.S. lost tens of thousands of honey bee colonies. This comprised 30-35 percent of the nation’s pollinator stock. The reasons for this swift devastation were a complete mystery at first. It was also unclear whether such losses fell within the range of normal winter casualties or whether they constituted a cause for real alarm. The chief symptom was a low number of adult bees in the hive, and the cause seemed to be sudden early death.

As the massive die-off continued, agricultural experts began referring to the scary phenomenon as Colony Collapse Disorder. Such a quick decimation of the honey bee population had never occurred before. Possible causes were investigated. One culprit was thought to be the varroa mite, a parasite that sucks the blood of adult and larval bees. This weakens the hives and leaves them vulnerable to viral devastation. But the varroa mite, along with others pests, had been afflicting bee populations for a long time without wreaking such widespread destruction. Some new influence was causing the bees to be particularly weak and susceptible to parasites and viruses.

Scientists considered the effects of genetically modified crops on the overall ecosystem. Others focused on environmental contaminants – particularly, the introduction of new pesticides to agricultural land. One of the chemicals most frequently linked to bee decline is also the one most widely used throughout the world: Imidacloprod, a member of the neocontinoid family. Neocontinoid pesticides have come to be seen as the most significant threat to bee populations, wreaking more havoc than such factors as habitat loss and disease.

In mid January of this year (2013), scientists from the European Food Safety Authority, working with experts from across Europe, concluded that “only uses on crops not attractive to honey bees were considered acceptable” where imidacloprid was concerned. Bees are exposed to this pesticide through the nectar and pollen of plants that have been treated with it. The proven dangers of imidacloprid have cast doubt on the safety of the entire family of neocontinoids. France, Germany, Italy and Slovenia have already begun implementing bans on some uses of these chemicals. This initiative has not yet been taken up by the U.K. or the U.S.

To ensure not only the fragile balance of the worlds’ ecosystems but also the safety of our food supply, we need to take steps to halt the poisoning of our bees and practice more careful stewarding of their populations.

Image Credit: iStock Photo

Reference:

Ellis, J., Evans, J., & Pettis, J. (2010). Colony losses, managed colony population decline, and Colony Collapse Disorder in the United States Journal of Apicultural Research, 49 (1), 134-136 DOI: 10.3896/IBRA.1.49.1.30

Tokarz, R., Firth, C., Street, C., Cox-Foster, D., & Lipkin, W. (2011). Lack of Evidence for an Association between Iridovirus and Colony Collapse Disorder PLoS ONE, 6 (6) DOI: 10.1371/journal.pone.0021844

28Jan 2013

Beliefs and Questions About the Paranormal

Jason Carr ⋅ 17 Comments

While people of different beliefs from all over the world believe in an afterlife, many of them can’t seem to agree with each other or accept views other than their own. Yet, men have talked about the supernatural since the beginning of time. Recently, authors like Bill Guggenheim, Dr. Raymond Moody, and Dr. Eben Alexander have written books that explore the existence of the consciousness after death.

When science cannot easily explain how things happen, such as paranormal activity, people question whether the phenomenon is true. As in religion and politics, many attribute different meanings to the words and then argue about who is right. Do angels exist? Do they differ from spirit guides? If everything is energy, where do people go when they die? If the Wise Men followed the star in the East, did they use astrology?

Christians believe in life after death. So do metaphysicians, and Muslims. Why, then, is there so much controversy and skepticism of other people’s views? If there is an afterlife, should we doubt near death experiences? For some, the question becomes one of whose experience is authentic. Is it the person with whom they agree? In the Western world, for instance, many doctors give little credence to alternative medicine. But what about the similarities between descriptions of the nervous system and the chakras or the meridians? All of these methods deal with physical anatomy and the vital life energy that stems from the brain, spinal cord, and organs.

Another example is the similarity between the halos seen on early paintings of religious figures and the concept of angels having wings or humans having auras. People sometimes say they have “bad feelings” about emotions or events, and spiritual healers say that “blocked energy” causes disease. Do both of these mean the same thing?

In Hello from Heaven, authors Bill and Judy Guggenheim discuss their research on ADCs, forms after death communication that occur spontaneously, without the help of mediums or other forms of assistance. After interviewing over 3,000 people about their firsthand experiences, the Guggenheims estimated that somewhere between 50 and 100 million people had experienced episodes they interpreted as being messages from loved ones.

In the 1970s, Dr. Raymond Moody brought the phenomenon of near death experiences, or NDEs, to the national awareness with his first book, Life after Life. After four decades or study, Dr. Moody still says that, based on what his patients have told him, he has no doubt the people he has interviewed have experienced a glimpse of the afterlife.

Late last year, the concept of the NDE gained greater exposure with the publication of Dr. Eben Alexander’s Proof of Heaven. A skeptical neurosurgeon who contracted a deadly form of meningitis before slipping into a coma, Dr. Alexander wrote about his brief look at the near death experience. As in all accounts of the supernatural, however, skeptics challenged Dr. Alexander’s claims.

While no one knows for certain the answer to any of these questions, well-respected writers and philosophers have spoken of life after death for centuries. Edgar Cayce, an early 20th century Sunday School teacher known as the Sleeping Prophet, not only believed that people communicate with the astral realm, but he also believed in reincarnation. Emanuel Swedenborg, eighteenth century Swedish theologian, philosopher, and scientific investigator, spent much of his life attempting to explain the supernatural and heavily influenced the work of writers like William Blake and Henry James, as well as mystics like Raymond Moody and Edgar Cayce.

In 1890, the Swedenborg Society summed up their mentor’s teachings in the following statement:

“There are two worlds, a spiritual world where angels
and spirits are, and a natural world where men are.”

Although all of these stories of the supernatural have common threads, they also vary in details. Nevertheless, one common truth lies at the heart of all of these great teachings, from Buddha and Jesus to Mother Teresa and the Dalai Lama. Living beings are all part of one great force, and love is the glue that holds them together.

Reference:

Mobbs D, & Watt C (2011). There is nothing paranormal about near-death experiences: how neuroscience can explain seeing bright lights, meeting the dead, or being convinced you are one of them. Trends in cognitive sciences, 15 (10), 447-9 PMID: 21852181

Feinsod M, & Langer KG (2012). The philosopher’s swoon–the concussion of Michel de Montaigne: a historical vignette. World neurosurgery, 78 (3-4), 371-4 PMID: 22381306

18Jan 2013

Studying Ancient Earth’s Geochemistry

Jason Carr ⋅ 2 Comments

Image Credit: University of Washington

Researchers still have much to learn about the volcanism that shaped our planet’s early history. New evidence from a team led by Carnegie’s Frances Jenner demonstrates that some of the tectonic processes driving volcanic activity, such as those taking place today, were occurring as early as 3.8 billion years ago. Their work is published in Geology [citation below].

Upwelling and melting of the Earth’s mantle at mid-ocean ridges, as well as the eruption of new magmas on the seafloor, drive the continual production of the oceanic crust. As the oceanic crust moves away from the mid-ocean ridges and cools it becomes denser than the underlying mantle. Over time the majority of this oceanic crust sinks back into the mantle, which can trigger further volcanic eruptions. This process is known as subduction and it takes place at plate boundaries.

Credit: Image of southwest Greenland by Jacques Descloitres, MODIS Land Rapid Response Team, courtesy of NASA Visible Earth.

Volcanic eruptions that are triggered by subduction of oceanic crust are chemically distinct from those erupting at mid-ocean ridges and oceanic island chains, such as Hawaii. The differences between the chemistry of magmas produced at each of these tectonic settings provide ‘geochemical fingerprints’ that can be used to try to identify the types of tectonic activity taking place early in the Earth’s history.

Previous geochemical studies have used similarities between modern subduction zone magmas and those erupted about 3.8 billion years ago, during the Eoarchean era, to argue that subduction-style tectonic activity was taking place early in the Earth’s history. But no one was able to locate any suites of volcanic rocks with compositions comparable to modern mid-ocean ridge or oceanic island magmas that were older than 3 billion years and were also free from contamination by continental crust.

Because of this missing piece of the puzzle, it has been ambiguous whether the subduction-like compositions of volcanic rocks erupted 3.8 billion years ago really were generated at subduction zones, or whether this magmatism should be attributed to other processes taking place early in the Earth’s history. Consequently, evidence for subduction-related tectonics earlier than 3 billion years ago has been highly debated in scientific literature.

Jenner and her team collected 3.8 billion-year-old volcanic rocks from Innersuartuut, an island in southwest Greenland, and found the samples have compositions comparable to modern oceanic islands, such as Hawaii.

“The Innersuartuut samples may represent the world’s oldest recognized suite of oceanic island basalts, free from contamination by continental crust”, Jenner said. “This evidence strengthens previous arguments that subduction of oceanic crust into the mantle has been taking place since at least 3.8 billion years ago.”

Source: Carnegie Institution

Reference:

Jenner, F., Bennett, V., Yaxley, G., Friend, C., & Nebel, O. (2013). Eoarchean within-plate basalts from southwest Greenland Geology DOI: 10.1130/G33787.1

Svensen H (2012). Geochemistry: Bubbles from the deep. Nature, 483 (7390) PMID: 22437609

03Dec 2012

How is Solar Energy Stored?

Jason Carr ⋅ 1 Comment

Many people with solar panels installed in their home don’t realize that the thermal energy collected by the panels can be stored for later use. There are indeed several ways to store solar energy. It can be stored in a packed bed, in a heat-of-fusion storage unit or even in water.

Image Credit: Optics InfoBase

Packed Bed
Also known as thermal energy storage systems, packed beds are containers that hold small objects capable of storing solar energy. The objects, sometimes referred to as the packing material, may be stones, Raschig rings or any other spherical particles. Some packed beds contain structured packing instead of small, individual particles. Structured packing typically consists of corrugated plates of perforated embossed metal or, alternatively, wire gauze. In addition to packing material, a packed bed can also contain catalyst adsorbents such as nitrogen enriched activated carbons or zeolite pellets.

Image Source: Next Big Future

Heat-of-Fusion Storage Unit
Heat-of-fusion storage units are usually used to store larger amounts of energy than packed beds are able to. Also known as phase-changer units, these devices store solar energy in a chemical that changes phase from solid to liquid in order to act as a vehicle for storage. The clever thing about the whole storage process is that it’s the solar energy itself that enables the chemical to change to its liquid phase. Once stored in the chemical, the thermal energy can be tapped at a later point in time. Tapping into the energy allows the chemical to return to its solid form.

Water
As with chemical liquids, hot water can both be produced by and store solar energy. In a home with access to solar power, the hot water tank will fill up during daylight hours. The water in the tank can then be used as and when needed. Water doesn’t necessarily have to be in such a tank to store solar energy. Swimming pools are also often used as storage units, being heated by the very same solar energy they store. A cover is usually put over the pool when it’s not in use, in order to retain heat and thus maintain the water’s warm temperature.

Thanks to these devices and methods, solar energy isn’t just for use when the sun is out. As long as enough thermal energy has been stored away, a person can have a hot bath or take a swim in a heated pool in the middle of the night, if they so wish.

19Nov 2012

The Hierarchical Structure of DNA

Jason Carr ⋅ 5 Comments

Introduction
All life on Earth is based on building blocks, known as DNA (deoxyribonucleic acid), which exists in the form of a double helix. DNA is a highly elaborate and modular molecule with different levels of hierarchical complexity. In this post, we will examine some of the concepts about DNA. For those of you that are interested in fields such as astrobiology, transhumanism, and similar areas, it’s important to understand DNA as it has a direct bearing on much of the research being done in these emerging sciences today.

DNA Composition
DNA is made up of nucleotides, which are themselves constructed from a molecule of sugar, a molecule of phosphate, and a base. The base is the most crucial part of the molecule as it is essentially the carrier of the genetic information, that when combined with other bases, codes your genetic makeup. Simply put, DNA is an amazing biological molecule, which essentially makes you… you.

Image Credit: University of Utah

Bases
As mentioned, DNA at its simplest level is made up of a combination of bases; Adenine (A), Cytosine (C), Guanine (G), and Thymine (T). These bases exist in a chain on each strand of the double helix and join up in between the strands as complementary pairs of A-T and C-G. This sequence of base pairs is what codes for proteins to be made in your body, and thus is responsible for your appearance, your metabolism and thousands of other functions and features.

Genes
Sequences of bases that code for specific proteins to be produced are known as genes. They can be anywhere from only a few bases in length, to several million, with the average length in the human genome being approximately 3,000. For example, you can have a gene that determines eye color, or a gene that dictates the pigment of your skin. Different forms of a gene are known as alleles, so the gene for eye color has green, blue and brown alleles.

DNA Strands
A DNA strand is made up of thousands upon thousands of genes, and also what is known as junk DNA. This junk DNA does not have a function, or rather, it does not have a function that is currently understood or known of in the scientific community. These DNA strands form a double helix, which is two strands of DNA joined at their complementary bases, in a spiral structure.

Images and animations are courtesy of the National Human Genome Research Institute’s Talking Glossary.

Chromosomes
Chromosomes are tightly wound bundles of DNA strands, that look like two arms joint at the centromere, with the short arm designated “p”, and the long arm designated “q”. Two chromosomes join at the centromere to form a chromosome pair, which structurally resembles an “X”. The chromosomes are found in the nucleus of the cell, from where they replicate to form duplicates of themselves during cell division, or take part in the transcription/translation process whereby proteins are created from the genetic code.

DNA is complex
DNA, even when broken down into its constituent parts is incredibly complex and because of this, errors can easily creep into the code. Genetic disease and cancer typically come about due to these errors in the genome, and are exponentially copied during the copying and division of cells. So, DNA and its complexity are both a blessing and a curse but without it, life as we know it would not be possible.

Helpful DNA-related Resources:

The National Human Genome Research Institute fact sheet Deoxyribonucleic Acid (DNA) provides an introduction to this molecule.
Information about the genetic code and the structure of the DNA double helix is available from GeneEd.
For additional information about the structure of DNA, please refer to the chapter called What Is AGenome? in the NCBI Science Primer. Scroll down to the heading “The Physical Structure of the Human Genome.”
The New Genetics, a publication of the National Institute of General Medical Sciences, discusses the structure of DNA and how it was discovered.