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TRIVIA ARCHIVE: 20122013

TRIVIA QUESTIONS

Using his AC current generator, what device did Tesla build that could take low frequencies and step them up to extremely high frequencies?

The Tesla coil

In 1891, Tesla patented a device known as the Tesla coil that took ordinary household current of sixty cycles per second and increased it to extremely high frequencies, to the hundreds of thousands cycles per second.

Tesla considered this invention to be his greatest. He used it to conduct innovative experiments in lighting, phosphorescence, x-ray generation, electrotherapy, and the transmission of electrical energy without wires.

Tesla's research brought him into the invention of wireless communication. Who is often credited with the invention of radio?

Guglielmo Marconi

Working with his newly created coils, Tesla discovered he could transmit and receive powerful radio signals when they were tuned to resonate at the same frequency.

When a coil is tuned to the signal of a particular frequency, it magnifies the incoming electrical energy through resonant action.

Tesla applied for several basic radio patents in 1897 and was granted them in 1900. At the same time an Italian experimenter, Guglielmo Marconi was also working with his own device for wireless telegraphy. When he applied for patents in the United States he was turned down repeatedly because of the priority of Tesla’s patents.

Marconi used some of Tesla’s wireless ideas and on December 12, 1901, Marconi was able to transmit and receive signals across the Atlantic Ocean. When asked about Marconi’s achievement, Tesla commented, “Let him continue. He is using 17 of my patents.”

Yet in 1904, the U.S. Patent Office suddenly reversed its decisions and granted Marconi the patent for the invention of radio.

In 1909, Marconi won the Nobel Prize for Physics in recognition of his work in the development of wireless telegraphy. Tesla was furious and sued for copyright infringement. It wasn’t until 1943 that the U.S. Supreme Court finally reversed the decision and awarded Tesla the patent for radio. Unfortunately, Tesla was no longer alive, having died a few months previously.

Successful inventors need financial backing. Tesla teamed with George Westinghouse on the hydroelectric power plant at Niagara Falls. At the end of the 19th century, another prominent New York financier agreed to lend Tesla money to build an extensive laboratory on Long Island. Who was it?

J.P. Morgan

Tesla’s lifelong obsession was the wireless transmission of energy. In 1900, J.P. Morgan invested in a new laboratory on Long Island, N.Y. called Wardenclyffe. The site, designed by the prominent architect Stanford White, was to be a small city with houses, stores, and buildings to house 2,500 workers.

The centerpiece of the lab was to be a tower that could transmit messages, news, stock reports, weather warnings, and personal messages across the ocean wirelessly. The Wardenclyffe Tower began 120 feet below ground, rose 187 feet above ground, and was to be capped with a 55 ton sphere of steel.

Tesla experimented there for only a few days before creditors began to confiscate equipment for non-payment of debts. The tower was never finished and was completely destroyed in 1917 when the US government suspected German spies might use it to relay military messages during the First World War.

This investment was considered to be one of JP Morgan’s failures and Tesla’s greatest defeat.

In 1960, The Grand Conference on Weights and Measures dedicated the term “tesla” as a unit of measure. What does a tesla measure?

Magnetic field strength

The earth itself is a magnet that can generate electricity utilizing frequencies as a transmitter. All that is needed on the other end is a receiver.

In 1888, Tesla realized that he could rotate a magnetic field if two coils at right angles are supplied with AC current 90° out of phase. This was a fundamental discovery in physics. It helped create the field of magnetic resonance imaging (MRI). MRIs are a powerful diagnostic tool in medical imaging.

Radio signals can be elicited from the atoms in soft tissue when exposed to an electromagnetic field. These signals are transmitted and used to construct a computerized image of the interior of the body. The higher the signal, the higher the quality of the image.

The strength of the magnetic field is measure in gauss (G) or tesla (T) units.
1 Tesla = 10,000 Gauss

How many Nobel Prizes did Nikola Tesla win?

He won the same amount as Thomas Edison. Zero.

Tesla thought that everything we need to understand the universe is around us at all times. He believed in harnessing the forces of nature to human needs. He was green.

He anticipated worldwide wireless communication. He was visionary.

Tesla made a great deal of money on his patents but then spent even more on his experiments. He died penniless. He was not a businessman.

Tesla had keen memory and the ability to visualize and construct complicated objects in his mind’s eye. He thought long and hard before physically assembling them. He believed he might be the hardest-working man if thought is equivalent to labor.

He was a genius.

Atoms are formed from electrons, protons, and neutrons. Which two types of particles form the atomic nucleus?

Protons and neutrons

Electrons are placed at a distance, outside the nucleus.

All elements are made up of atoms. Atoms are the smallest indivisible unit of an element. Atoms are made up of protons, electrons, and neutrons.

Protons have a positive electrical charge (+), electrons have a negative electrical charge (-), and neutrons are neutral (0) with no electrical charge.

Protons and neutrons cluster to form a densely packed core of positive charge, the nucleus of the atom.
Unlike charges (+ and -) attract each other. Like charges (+ and +, - and -) repel each other. Atoms, in their elemental form, have a balanced amount of positive protons and negative electrons.

Which particle is necessary for the formation and breakdown of chemical bonds?

Electrons

An atom is mostly empty space.

The nucleus is a densely packed core of positive charge. Negatively charged electrons are in constant movement outside and around the atomic nucleus. It is the attraction of opposite charges that bind the atom together.

Electrons with the least amount of energy are closest to the nucleus and those with a greater amount of energy are further away.

Atoms can share acquire, lose, or share electrons with other atoms. This action results in chemical bonds  that hold atoms together to form molecules. Reactions generally bring reactants to a more stable state.

What do we call the flow of electrons between atoms?

Electricity

When the charges are out of balance, an atom is either positively or negatively charged. The switch between one type of charge to another allows electrons to flow from atom to atom. This flow of electrons is what we call electricity.

Everything in the universe is made up of atoms.

In our body, neural signals are electrical in nature. Electrical signals within the human body are fast. They allow for nearly instantaneous response to control messages.

What do we call the type of electricity that has an imbalance of electrical charges within or on the surface of a material?

Static electricity

Some atoms hold onto their electrons more tightly than others.  Certain materials will “capture” electrons when they come into contact with other matter. When separated, a charge imbalance may occur. Electrons have built up on one surface and will remain there until they are discharged or moved.

Since the charges are identical, the electrons repel each other and try to separate.

Because this electricty does not flow through wires or conductor that transmit energy, it is called static.

When an atom gains an electron, is it more positively or negatively charged?

Negatively

An electron is a subatomic particle with a negative charge. An atom acquiring an electron would increase in negative charge and decrease in positive charge.

The addition of electrons is called reduction because the negative charge has reduced the amount of positive charge.

The loss of electrons from a substance is called “oxidation” because the positive charge is increased.

When an electron moves from one molecule to another, is it considered an oxidative reaction or a reduced reaction?

Both

When an electron moves from one molecule to another, one molecule loses an electron and other gains an electron. You cannot have one without the other. Reduction and oxidation occur simultaneously. Hence is it shorted to “redox” reaction.

Not all redox reactions involve the complete transfer of electrons. It is still considered a redox reaction when substances share electrons because positive and negative charges have shifted.

No chemical bonds are broken in redox reactions but changes take place in the molecular structure of the molecules and the molecules nearby. This shape shift enables electrons to move between molecules.

Many biological processes rely on redox reactions. The relocation of electrons releases energy stored in organic molecules. This energy is ultimately used to synthesize ATP.

How fast does an electron move in a wire?

Quite slowly

An electron, if pushed, can travel nearly the speed of light in open space like in outer space or in an accelerator.

Traveling through matter, in this case a wire, slows it down to snail’s pace. For electron to move down a wire, it interacts with many atoms along the way. They kind of drift, moving at about 1 meter per hour. 

While electrons travel slowly within a wire, their interaction propagates into a wave. The exact length of time it takes for an electromagnetic field to travel in wire depends on the type and thickness of the wire but it can travel nearly the speed of light.

Why are wires usually made of metal?

Metals are conductors

The physical and chemical behavior of an atom is determined by its outermost electrons. Metals readily lose electrons in their outermost shell.

Wire, being made of metal, is an excellent conductor as these electrons flow freely from particle to particle with little resistance.

Yet as electrons flow in a wire, they collide with the metal atoms and move them faster. This friction produces heat. The faster the atoms move, the hotter the wire gets.    

Your toaster is a good everyday example of electrons making heat. Metals, conductors, and electrons all help to make your morning breakfast.

If electrons pass freely through conductors, what do we call those materials that resist the flow of electrons?

Insulators

The difference between conductors and insulators is how strongly the electrons are held in the chemical bonds to the atom.

Electrons move easily through metals. Non-metal elements hold their electrons more tightly in chemical bonds and resist the motion of charge through them.

Plastics make good insulators because they have few or no free electrons. Copper wires are coated with insulating material to prevent the charge from spilling out.

With enough voltage applied, however, any insulating material will break down and start to leak electrons.  This is often a dangerous short-circuit spark.

As in a wire, electrons move through our bodies generating energy. What is the name of the series of compounds through which electrons move and create chemical energy in the form of ATP?

Electron transport chain

The electron transport chain is a series of redox active compounds found on the inner membrane in mitochondria and in the thylakoid membrane in choloroplasts.

Electrons pass sequentially through the chain, meeting compounds with increasing affinities for electrons until they are finally transferred to oxygen, the ultimate oxidant.

As they pass, they electrically and chemically charge the membrane.  This charge is used to drive synthesis of ATP, stored chemical energy for cell survival and growth.

It is how plants extract energy from sunlight and animals extract energy from food.

In 1966, a seminal paper on how electrons transfer in biology was published the Biophysical Journal. Who co-authored the paper? Hint: he had very close ties to the Department.

Britton Chance

Britton Chance and Don DeVault co-authored a paper “Studies of Photosynthesis using a Pulsed Laser” in the Biophysical Journal.

In it, they describe that electrons don’t pass from molecule to molecule by collisional contact, but instead quantum mechanically “tunnel”  through the molecular space in the proteins.

Biological electron tunneling can take place even near absolute zero of temperature where nearly all molecular motion has stopped.

What is the dominant factor in determining the rate in which electrons move through biological membranes?

Distance

Different parameters affect the movement of electrons through molecules, including the molecules’ vibration and environment, but the predominant factor is distance.

Chris Moser and Les Dutton calculated the rate at which electrons tunnel through proteins based on the distance between the molecules. This calculation has become known as the “Moser Dutton Ruler”.

Nature likes a distance of 14 Angstroms or less (1 millimeter = 10,000,000 Angstroms) to maintain a working rate of electron transfer through chains of redox molecules. The closer the molecules, the faster the transfer.

Every time we breathe oxygen into our bodies, we activate electron tunneling, ultimately making biochemical energy in the form of the molecule ATP.

What is the most magnetic of all naturally occurring minerals on Earth?

Magnetite

Magnetite is a naturally-occurring mineral found in almost all igneous and metamorphic rocks. Known for its ability to attract small pieces of iron, it was used as an early form of magnetic compass.

Crystals of magnetite have been found in bacteria and in the brains of some animals.

Magnetic sensitivity is common in birds. Magnetite has been found to be concentrated in the birds’ beaks and, along with visual clues, thought to be responsible for their ability to migrate over thousands of miles.

What is another way that birds can sense the magnetic field?

With their eyes

The eyes of migrating birds contain a yellow flavin-containing protein called cryptochrome. When the flavin absorbs daylight, the excited flavin electron acquires a spin that is now sensitive to magnetic fields.

This changes the ability of the electron to tunnel to other centers in the protein and gives the bird a visual signal of the direction north.

The Dutton lab is designing artificial magnetic field-sensitive proteins to explore how this works.

Do pigeons migrate?

Some do, some don't

Bird migration is regular seasonal movement. Birds will search for hospitable climates and abundant resources as seasons change. There is a high cost associated with migration including mortality and predation. Animals will not make that effort without good reason to do so.  

Several species of pigeon (Band-tailed Pigeon, Mourning Dove) will migrate to warmer climates in winter to take advantage of changing food supplies.

The familiar type of pigeon we see in urban areas is the Rock Dove. It does not migrate because there is no reason for it. Resources are plentiful in cities. Cities provide shelter, warmth, and discarded human food.

Still, like migrating birds, these pigeons can orient themselves easily. They have outstanding homing capabilities and can travel long distances to return to their nesting areas.

What is the difference between pigeons and doves?

Not much

There is no strict division between pigeons and doves. They both have small rounded heads, slim bills, plump bodies with dense soft feathers, tapered wings, scaley legs, and make cooing calls.

Pigeons and doves constitute the bird clade Columbidae, which includes about 310 species. Generally speaking, the word “dove” is used for the smaller species and “pigeon” for the larger. Usually the terms are used interchangeably.

What species of pigeon went from being one of the most abundant birds in the world during the 19th century to extinction at the beginning of the 20th century?

The passenger pigeon

Estimates range from 3 to 5 billion passenger pigeons living in North America when the Europeans first arrived. It is believed that this species constituted 25% to 40% of the total bird population in the United States.

The passenger pigeon resembles a larger, more brightly colored Mourning Dove.

It was a gregarious animal that lived in large numbers to ensure successful breeding. The immense groups they formed were almost beyond comprehension. A single flock could contain hundreds of millions of birds.

Passenger pigeons filled forests eating tree nuts and insects. They would migrate in the spring and fall. They had a propensity for eating everything and then taking over the sky.

In 1813, John James Audubon described a flock moving 60 miles an hour, a mile in width, obliterating the noonday sun, and taking three days to pass over.

What was responsible for the demise of several billion passenger pigeons?

a) Disease
b) Human predation
c) Dwindling resources

b) Human predation

Passenger pigeons tasted good and were easy to kill. In the days before refrigeration, they were like a living convenience store.

Initially, the killing of passenger pigeons did not make much of a dent in the enormous population. As society grew more modern, the location of nesting birds could be telegraphed. Professional hunters chased them around the country all year long.

In 1878, the refrigerated rail car was introduced and tens of thousand passenger pigeons could be crammed into cars and transported to large cities hundreds of miles away. Restaurants could offer wild game on their menu.

At the same time there was an explosion in logging which destroyed their habitat.

In its lifetime, little was known about passenger pigeons besides how to catch, kill, and cook them.

When did the last passenger pigeon die?

1914

Many view the story of the passenger pigeon as a cautionary tale. It is a complicated history of industry and economics versus nature and conservation.

The passenger pigeon lived in collaboration on a giant scale but may have died because of it. When massed together, they were easily slaughtered. The surviving birds could not exist in smaller flocks.

In the 1880s and 1890s, when it was clear the passenger pigeon was doomed, several ineffective laws protecting the pigeon were passed. By then, the number of remaining birds was too few to successfully reestablish the species.

In 1900, a boy in Ohio killed what was thought to be the last wild passenger pigeon. A small captive population remained at the Cincinnati Zoo including a pair named George and Martha. By 1910, only Martha remained.

On September 1, 1914, Martha died. She was 29 years old. She is now known as a symbol for the threat of extinction.

The public interest in the demise of the passenger pigeon helped to strengthen conservation laws. These laws have helped save many other migratory species.

What is the name of the controversial program that would like to resurrect extinct species?

De-extinction

De-extinction is the process of creating an organism which is a member of an extinct species. The most popular methods are cloning and selective breeding.

The sentimental attachment to the passenger pigeon and its extinction has led a team of scientists to try to bring it back to life. Reconstructing the passenger pigeon genome is the first step in its de-extinction. Genes for key passenger pigeon traits like its long tail or orange-colored breast need to be identified and then spliced into the genome of its closest living relative. This doctored DNA could be injected into the eggs of band-tailed pigeon, and successive generations would be bred and selected for passenger pigeon traits.

This idea is not without controversy. If successful, any resurrected species would not be returning to its original habitat. It is unclear how its reappearance would fit into the current ecosystem.

Critics argue that time is better spent serving existing species.

What slang expression was invented to describe a bird that was used to lure other birds into a trap?

Stool pigeon

One quick method for capturing passenger pigeons was to use a single bird as a decoy. A bird was tied to a stool (or a block of wood) that would rise up and down when pulled by a cord. A group of wild birds would be fooled into thinking that it was quietly feeding. When they joined him, they were netted.

The original definition of stool pigeon was a bird decoy (early 1800s) but evolved into anything that betrays its own group.
As years went on, the definition broadened into a police informer (late 1800s).

One of the most famous birds alive today is a Red Knot who has migrated 350,000 miles in his lifetime. Scientists call him “B95”. What is he also known as?

Moonbird

Red Knots are medium-sized shore birds, about the size of a starling, that breed in the high Arctic. They have one of the longest migrations of any bird – 9,000 miles – from the Arctic to the southern tip of South America.

In February 1995, researchers banded a 2-year-old Red Knot with the number “B95” and have tracked him to this day. He is the oldest living Red Knot on record.

Being 20 years old, he has logged at least 350,000 miles in his lifetime. Having flown the distance from the Earth to the moon and halfway back, he has been dubbed “Moonbird”.

During spring migration Red Knots, including Moonbird, stop to refuel on their way back to the Arctic. Where do they stop to rest, relax, and eat horseshoe crab eggs? (Hint: it’s local)

Delaware Bay

Being shore birds, Red Knots migrate to coastal areas. During their hemispheric migrations they make a local crucial stopover. They arrive in the spring at the Delaware Bay just as horseshoe crabs are spawning. They stay for about 2 weeks, doubling their weight by gorging on eggs before moving on to complete their journey north.

It is estimated that 90% of the entire population of the Red Knot subspecies C. c. rufa can be present in the Delaware Bay in a single day.

B95 (a.k.a. Moonbird) was spotted there this past May. His long life and stamina has endeared him to researchers. This 4-ounce bird has become a mascot for shorebird conservation efforts. Most shorebirds are in decline. Red Knots are the most imperiled due to the overharvesting of horseshoe crab eggs but as resources rebound, so do the Red Knots. Numbers are increasing and through it all, there has been Moonbird.

Which bird has eyes that are larger than its brain?

The ostrich

The ostrich is the world’s largest bird and is native to Africa. Ostriches are strong runners and can sprint up to 43 miles per hour. Their wings, useless in flight, help them change direction while running.

Ostrich eyes are the largest of any land vertebrate: axial length = 38 mm and of globose shape with an anterior focal length of 21.8 mm.* Ostriches’ eyes take up approximately two-thirds of their heads so there is little room left for brains. They do, however, have exceptionally good sight both near and far.

Their eyes weigh ~60 grams and their brains ~40 grams.

Despite their extraordinary speed and vision, ostriches are not very good at eluding predators. Without a lot of brain power, they tend to run in circles.

*Martin, Ashash, and Katzir (2001) Ostrich Ocular Optics. Brain, Behavior, and Evolution 58(2):115–120.

Which bird has the largest brain in proportion to its size and is known for its incredible memory?

The hummingbird

Hummingbirds are very small, weighing less than a nickel. Their metabolism is extremely high so they are in constant search of food. These tiny birds must consume more than their weight every day or starve to death.

90% of their diet is nectar. Nectar is a mixture of glucose, fructose, and sucrose, and is a poor source of nutrients. Hummingbirds supplement their diet with insects and spiders.

Hummingbird brains weigh ~4.2% of its body size, the largest proportion in the bird kingdom. That part of the brain related to learning and memory is particularly large, up to five times larger than those found in seabirds, songbirds, and woodpeckers. This excessive brain power has made them skilled and efficient foragers.

They have excellent memories. They visit hundreds of flowers each day and remember where each one is located and how long it takes a flower to refill with nectar once it has been drained.

In 1782, the American Bald Eagle was depicted in the Presidential Seal of the United States. Benjamin Franklin was disappointed. What bird did Ben prefer to be our national symbol?

The turkey

In 1782, a national seal was created for our newly formed United States. The American Bald Eagle is depicted as a symbol of strength and power.

Benjamin Franklin lamented the choice of birds in a letter to his daughter in 1784.  He felt the eagle was a bird of “bad moral character” that “did not get his living honestly.” He had seen eagles stealing fish from hawks and become intimidated by much smaller birds.

He felt that the turkey, on the other hand, was a much more respectable bird. Although it was “a little vain and silly,” it was “a true original native of America” and “a bird of courage.”

In the early days of our country, Ben related to the rebel spirit of the turkey who “would not hesitate to attack a grenadier of the British Guards who should presume to invade his farm yard with his red coat on.”

What characteristic makes birds unique?

  • a) Ability to lay eggs
  • b) Ability to fly
  • c) Feathers

c. Feathers

Egg laying is not a distinctive trait of birds since it is common in many species of animals. Birds like emus and ostriches can’t fly so flight is not a distinguishing characteristic either.

Feathers, on the other hand, are what sets birds apart from all other animals. Feathers are made from keratin, just like our hair and fingernails.

If an animal has feathers, it is a bird.

What do birds use their feathers for?

  • a) Mating
  • b) Territorial dominance
  • c) Body temperature regulation
  • d) Camouflage
  • e) Flight
  • f) All the above

f; all the above

Mating: In some species, the coloring and markings on the male bird has a direct impact on his mating success

Territorial dominance: Some research indicates that birds in good health are able to produce feathers with brighter colors. In establishing a nesting territory, strong feather colors indicate that the bird is especially fit.

Regulation of body temperature: Feathers keep birds warm and dry.

Camouflage: The pattern and color of feathers helps birds elude predators by disappearing into their surroundings.

Flight: The strength, shape, and light weight of feathers gives birds the ability for sustained flight.

Which of the following senses is the weakest in birds?

  • a) Hearing
  • b) Seeing
  • c) Smelling

C. smelling

Like most animals, birds use their senses mainly to locate prey and avoid predators.

Vision is the most important sense for birds. Their eyes are more developed than human eyes. They have four types of color receptors and more nerve connections from the eye to the brain. Birds are also especially sensitive to sound.

The least useful senses for a bird are smell and taste (which is related to smell).

Because odors disperse quickly in open air, smelling seems to be the least useful method for a bird to locate food. In fact, some bird watchers wondered if birds could smell at all. Studies show that their olfactory organs are not well developed.

Although there are exceptions – kiwis will sniff out earthworms and vultures can smell meat – generally speaking, smell ranks well behind both sight and hearing as the sense birds rely for survival.

What do cows and chickens have in common that we humans do not?

Cows and chickens have more than one stomach

Cows have four stomachs to digest food and birds have two.

The first avian stomach is the proventriculus, which secretes acid for breaking down food. Birds that swallow entire fish or small animals have a well-developed first stomach to help digest bones.

The second stomach is the gizzard whose main function is to grind and digest tough food. The gizzard is a powerful muscle that pulverizes all the food the bird eats. Some birds will eat grit and small rocks that accumulate in the gizzard and helps to smash the food.

Owls swallow prey whole. The food is broken down as it passes back and forth between the two stomachs. Those parts that cannot be digested (fur, bones, and teeth) are pressed into a pellet and regurgitated before the owl can eat again.

What came first: the chicken or the egg?

The egg

If we are talking about any type of egg, then certainly species that laid eggs have been around long before the modern chicken. Fossil evidence shows dinosaurs laid eggs.

Egg-laying animals existed long before birds ever did – about 150 million years before birds.

Maybe a better way of wording the question is….
What came first: the chicken or the egg containing a chicken?

Again, it’s the egg

If a chicken is born from an egg, where did that egg come from? From a chicken? Wasn’t that chicken also born from an egg? Which came first?

This philosophical dilemma illustrating a vicious circle has been around for centuries.  Aristotle turned it over in his mind and concluded the bird and the egg must have always existed (even if only in spirit).

An egg containing a chicken could have been laid by a chicken or by a non-chicken. 

Living things evolve through changes in their DNA. Chickens evolved from non-chickens by mixing the DNA of the mother and father to form a new life. The replication of DNA is never one hundred percent accurate and often produces small changes in the new organism.

An egg-laying bird, very similar to a chicken, mated with another bird very similar to a chicken and gave birth to a mutant… which became the modern chicken. That chicken grew inside an egg. The egg came first.

Gradual evolution from one species to another via mutations accumulated over many generations.

What came first: the chicken or the egg laid by a chicken containing a chicken?

The chicken

What is a chicken egg? Is it an egg laid by a chicken or an egg containing a chicken? Some people believe a chicken egg is one laid by a chicken no matter what is inside. In this scenario, the chicken came first.

What is the next number in this sequence: 0, 1, 1, 2, 3, 5, 8, 13, 21, 34, ___?

55

Each subsequent number is the sum of the previous two.

This sequence of numbers was known to Indian mathematicians as early as the 6th century but became popularized in Europe by an Italian mathematician and businessman Leonardo Bonacci in his book “Liber Abaci” (“Book of Calculation”) in 1202. Bonacci’s nickname was Fibonacci and henceforth this series of numbers became known as the Fibonacci Sequence.

The mathematical ideas contained in the Fibonacci Sequence can be used to model or describe an amazing variety of phenomena in mathematics, science, art, and nature.

The ratio between the Fibonacci numbers is also significant. What is that ratio known as?

The golden ratio or the golden number

One Fibonacci number is divided by its immediate predecessor. As Fibonacci numbers increase, the ratios quickly converge on phi or 1.61803398875.

Fibonacci numbers and their relative ratios appear in mathematics and science but extend far beyond into the worlds of art and nature.

Fibonacci numbers in plant life

An example of Fibonacci numbers in nature: a five-petaled blossom on a 8-blossom stalk. (photo: M. Leonard)

Although no one can really explain why, Fibonacci numbers are found often in biological settings. Leaf arrangements in plants, patterns of florets on a flower, and the structure of hurricanes and galaxies, all show the surprising appearance of Fibonacci numbers and ratios.

In plant life, it has been suggested that this patterning is the most efficient way to maximize sunlight exposure to plant leaves. Even this tiny advantage could come to dominant over many generations.

Although nature may seem random there are many instances of mathematical order involving Fibonacci numbers.

In addition to this series of numbers, Fibonacci also brought something else Europe that revolutionized mathematics. What was it?

The Hindu system of writing numbers

Fibonacci traveled the Mediterranean world to study under the world’s leading mathematicians. He realized the Hindu system was a much more efficient and simpler way to do mathematics than the use of the old Roman numerals.

We now call this system Arabic notation since it came west through Arabic lands. Instead of letters representing numbers, Arabic numerals use the digits 0 – 9. This system was applied to bookkeeping, conversions of weights and measures, calculation of interest, and money exchanges.

Modern mathematics would be impossible without the switch from Roman numerals to Arabic numbers.

What hormone plays an important role in sleep cycles?

Melatonin

A key factor in our sleep-wake cycle is controlled by light. Light hitting our eyes sets off a cascade of events. Our brains are triggered to raise body temperature and release stimulating hormones to prepare for the day ahead.

As light dims, our brains set off another chain of reactions including the release of melatonin. Melatonin is a naturally-occuring hormone released by the pineal gland. It helps to regulate the sleep-wake cycle by chemically causing drowsiness and lowering the body temperature to prepare for sleep.

Known as a powerful antioxidant, melatonin’s primary function is to regulate our circadian rhythm.

It is sometimes called “hormone of darkness” because peak production of melatonin occurs during the night. When light returns, melatonin production ceases.

Light interferes with the release of melatonin, particularly one specific frequency of color. Which color is it?

Blue

In the days before artificial lighting, people rose and set with the sun. Exposure to daylight for certain lengths of time keeps our circadian rhythm regular.

Light is beneficial during daytime hours: it boosts attention, reaction times, and mood. Like sunlight, the blue rays of the light spectrum set in motion important biological responses. However, light can be disruptive at night. Light of any kind can suppress melatonin but blue light does so more powerfully.

Smart phones, tablets, and computer screens all emit light in the blue range. Light at night is the reason most people cannot get sleep. By being connected to our devices, we are “on” most of the time. If light never fades, melatonin will not be released.

By looking at light, and specifically blue light, our bodies are confused at the time of day. Our circadian rhythm is thrown off. Studies have shown that this can lead to depression and many other health problems.

How can cherries help you sleep?

They are packed with melatonin

Melatonin was first discovered in animals in the late 1950s. Later it was found in bacteria and fungi, and was ultimately found to be in plants as well.

Remarkably, melatonin functions in plants just as in animals. Melatonin levels in plants are very low or undetectable during the day with a considerable increase in darkness. Melatonin regulates plants’ circadian rhythm but also helps prevent damage from free radicals.

Melatonin has been found to be present in different parts of plants including leaves, stems, roots, and seeds.

Many foods contain small amounts of melatonin (eg. bananas, rolled oats, and corn) but sour cherries have been found to hold a large concentration. Studies have shown that drinking cherry juice before bedtime increased melatonin levels and sleep time.

Good news! Beverages made from plants also contain some melatonin including coffee, tea, wine, and beer.

What is the so-called “stress hormone”?

Cortisol

Your adrenal glands release cortisol in response to stress and low blood glucose.

Cortisol increases blood sugar, enhances the brain’s use of glucose, suppresses the immune system, and aids in the metabolism of fat, protein, and carbohydrates.

Cortisol levels are highest in the morning. It keeps you alert and energized throughout the day. Cortisol continuously declines to its lowest level during the first half of the night.

Melatonin and cortisol are inversely related. When cortisol is low, melatonin kicks in. And as night ends, melatonin is turned off and cortisol increases.

What is the so-called “fight-or-flight hormone”?

Adrenaline

Cortisol and adrenaline are part of your body’s complex natural alarm system. Both hormones are released by your adrenal glands in response to stress.

Unlike cortisol, adrenaline is responsible for immediate reactions. Adrenaline quickens your heartbeat, boosts oxygen supply, elevates blood pressure, and boosts energy for instant action.

Adrenaline is an early evolutionary adaptation allowing us to cope with dangerous and unexpected situations. Once the threat is passed, adrenaline levels return to normal.

This week's answer:

What neurotransmitter is thought to be the chemical responsible for maintaining mood balance?

Serotonin

Neurotransmitters are chemicals that relay signals between nerve cells throughout our body. Our brains use neurotransmitters to tell our hearts to beat, our lungs to breathe, and our stomachs to digest.

More that 90% of the body’s serotonin is found in the gastrointestinal tract and in blood platelets where it regulates intestinal movements. The rest is found in the central nervous system where it helps to regulate mood, appetite, sleep, and learning.

Disturbances in the nervous system can cause depression, anxiety, and panic attacks.  Some researchers consider serotonin the “Don’t Panic Yet” neurotransmitter because it helps alleviate adversity.

Pharmaceutical companies have shown great success in developing effective antidepressants that specifically boost serotonin levels in the brain.

Next week's question:

The brain makes its own serotonin. Why can’t it use the supply made in the gastrointestinal tract?

 

Past questions and answers are in the trivia archives: 2012 / 2013

Questions? Comments? Corrections? Contact Mary Leonard, mleonard@mail.med.upenn.edu

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