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TRIVIA QUESTIONS

True or false: natural gas is a fossil fuel.

Yes, of course.

Fossil fuels are formed when organic matter (remnants of plants and animals) is compressed under the earth for a very long time at very high pressure. This compression, combined with high temperatures found deep within the earth, breaks down the carbon bonds within the organic matter.

In the lower temperatures (shallower deposits) more oil is produced. At high temperatures (deeper deposits) more natural gas is created. Most of this gas is methane. Natural gas is lighter than air and rises to the surface. As it rises, gas may dissipate into the air at the surface but some will be “trapped” in porous sedimentary rocks near the surface of the earth.

Natural gas is colorless, shapeless, and odorless in its purest form.

If gas is odorless, why can we smell it?

We can’t.

The distinctive “rotten egg” smell we associate with gas is mercaptan that has been added before it is delivered to the end user. It is the mercaptan we smell. It is added to detect gas leaks.

The most attractive feature of natural gas is its combustibility; it gives off lots of energy when burned. Energy companies are excited by the fact that gas reserves are abundant in the United States. With our own source of energy, hopes are that we could become a cleaner and more self-sufficient nation.

In the past 20 years, a new process has enabled much more gas to be extracted from rock than ever before. What is this process called?

Hydraulic fracturing, or “fracking” for short, combined with horizontal drilling

Shale is a fine-grained sedimentary rock composed of mud containing clay minerals and quartz grains. It is made up of many thin layers and is easily broken apart along its laminations. Experts have known for years that shale held vast quantities of gas and oil in its natural fissures and pore spaces but it was not thought to be recoverable.

What is unique about the way shale is currently fracked is the ability to drill vertically into the earth, then make a 90° turn, and drill horizontally into the shale layer.

In hydraulic fracturing, a well is drilled at the surface and then pumped with a combination of water, sand, and various chemicals at a very high pressure. The shale is then blasted apart, fissures are created, and gas escapes.

Added to the fracking fluid is a proppant agent such as sand, ceramic beads, or other particulates that prevents the fracture from closing completely and allows gas to continuously flow. Because this type of technology is so new and atypical, gas from shale is referred to as “unconventional natural gas”.

Where is the largest shale formation found in the United States?

In Pennsylvania, New York, Ohio, West Virginia, and Virginia

It is called the Marcellus Shale and it is the largest source of domestic natural gas found so far in the United States. Because it has the potential to be the largest producing gas field in the United States, the Marcellus Shale has come under intense national scrutiny.

Gas companies see profits, environmentalists see damage to our natural resources, and politicians see it as a hot campaign issue.

How did the Marcellus Shale get its name?

It is named after the town of Marcellus, New York.

This is where the shale layer reaches the surface of the earth. The Marcellus Shale was formed in the Devonian Age (390 million years ago). At that time it was part of an ocean floor.

How many gallons of water are used in typical well using the hydraulic fracturing method?

4.5 million gallons

The word “hydraulic” comes from the Greek words hydor (water) and aulos (pipe). In addition to cooling and lubricating the drill bit, water is used to blast shale apart and carry the cuttings to the surface.

The water used in fracking has sand and a combination of chemicals added to it. Once water is extracted from the well, it needs careful disposal. It is usually held in pools until it can be removed. Water is most commonly transported to and from well sites by trucks.

This toxic byproduct of fracking is a growing concern for environmentalists and gas companies. Wastewater can partially treated and then discharged into rivers and streams possibly contaminating drinking water. Fracking fluid is also disposed of by injecting it deep into the ground.

Source: Hydraulic Fracturing Facts www.hydraulicfracturing.com

What phenomenon occurred in Youngstown, Ohio on December 31, 2011 that many believe is a direct result of injecting fracking fluid into the ground?

An earthquake

In a seismically sound area of Ohio, an earthquake measuring 4.0 in magnitude hit Youngstown just before the beginning of this year. It was the eleventh earthquake that year.

Officials and seismologists linked these quakes to disposal injection sites that store water from hundreds of fracking wells. It is known that injecting fluids into the ground can cause earthquakes, and that earthquakes can occur almost anywhere. The San Andreas Fault is well known because it runs almost the entire length of California but smaller faults can be found in lots of places.

Four fluid-injection wells in eastern Ohio have been prohibited from reopening indefinitely in the aftermath of recent seismic activity in the area. Suspending operations or even closing wells permanently will not guarantee fluids already disposed of will not cause future disturbances.

What chemicals are added to water and sand to make fracking fluid?

Not entirely known

Fracking fluid is a mixture of water, sand, and various chemicals. Additives help to lubricate the drill bit, slow bacterial growth, and prevent pipe corrosion. Hundreds of chemicals can be used to create a unique fracking fluid mix.

Some of the common compounds used in fracking: hydrochloric acid (commonly used as swimming pool cleaner), ammonium persulfate (bleaching agent in detergent and hair cosmetics), borate salts (laundry detergent), ethylene glycol (automotive antifreeze), isopropanol (glass cleaner, antiperspirant).

Many are well known but drilling companies are reluctant to release the exact composition of their fluid because they say it is proprietary information and a trade secret. Activists suspect the worst.

Where does Philadelphia get its drinking water?

The Delaware River Basin

The Delaware River is the longest undammed river east of the Mississippi. 15 million people get their drinking water from here.

The gas industry has applied for permits for hydraulic fracturing in the Delaware River Basin. The potential for gas and chemical leakage into our drinking water has forced the governors of New York, Pennsylvania, New Jersey, and Delaware to put a moratorium on drilling in this area.

The concerns about fracking are both economic and environmental. We need new types of energy and people need jobs. But…. can we spare so much water? What chemicals are used? Are they safe? Is living close to a well healthy? Can the back roads take the wear and tear of trucks? Can fracking fluid be safely disposed of? Can the gas industry be regulated as quickly as it is growing?

What is hydrology?

The study of ground water

Hydrology is the science that studies the distribution, circulation, and properties of water as it travels on and through land. It examines the biological, physical, and chemical processes of water after it falls to earth and before it returns to the atmosphere.

Water falls as snow or rain. It may soak through the soil, flow to rivers and seas, or be transpired through plants. It can be temporarily diverted from the cycle for use in homes and businesses, after which it is returned to the cycle. Water is in continuous movement changing states between liquid, solid, and gas. Eventually it is evaporated back into the atmosphere.

This process can be very short or could take millions of years.

What is the difference between a stream, a river, and a creek?

Stream is a general term for bodies of water with detectable currents confined by beds and banks.

A river is a large natural stream of fresh water flowing towards an ocean or sea.

Creeks (and brooks) are narrow and shallow streams with beds composed mainly of rock. They originate from mountainous water bodies or may come from out of underground water sources and usually flow into a river.

What happens to industrial waste after it is dumped into a river?

65% of the human body is composed of water so it goes without saying that water is necessary for our survival. Water is also crucial for the survival of cities and towns, which is why most urban areas are next to bodies of water. From rivers we get drinking water, water for agricultural and industrial purposes, land drainage, navigation by boat, fishing, beauty, and removal of waste.

When sewage is dumped into a river, it begins a biological process of decay. Waste can be diluted, dissolved, or settle to the bottom. Organisms in the water can filter or consume it. Rivers are self-purifying.

The major factor in determining how stable a river can be is the amount of oxygen it holds. Organic matter is destroyed by oxidation. But even self-purification has its limits. A river cannot be overwhelmed by pollution and be expected to cleanse itself.

As citizens became more concerned about pollution flowing into rivers, the U.S. government enacted wastewater standards in 1977. What is this law called?

The Clean Water Act

Cities don’t have much unpaved land so rain water that would normally be absorbed by the ground runs into sewers and eventually into rivers.

The Federal Water Pollution Control Act, enacted in 1948, was the first major U.S. law to address water pollution. This act was significantly reorganized and expanded in 1972. When it was amended again in 1977, it became known as the Clean Water Act.

The main purpose of this legislation was to make all U.S. waterways fishable and swimmable by 1983. It regulated what could be discharged into surface waters, funded sewage treatment plants, and managed quality standards.

In 1969, an incident drew national attention to the sorts of problems posed by dumping toxins into waterways. What U.S. river caught fire in 1969?

Cuyahoga River

On June 22, 1969, an oil slick and debris caught fire in the Cuyahoga River in Cleveland, Ohio. It is unclear what caused the fire but most people believe a spark from a passing train ignited the oil slick. Cleveland was a booming manufacturing town in the late 1880s and the early 1900s. Businesses there routinely polluted the river.

The 1969 fire was not the first time the river caught on fire. Fires also occurred in 1868, 1883, 1887, 1912, 1922, 1936, 1941, 1948, and 1952. The 1969 fire did not last long, just 30 minutes, but it helped spur the environmental movement and helped lead to the passage of the Clean Water Act three years later.

You may be surprised how much water it takes to bring products to your home. What uses more water to make? 1 gallon of milk or 1 gallon of wine?

Okay, let’s work this one out… by milk, we refer to cow’s milk. Cows need water for drinking and their pastures need water to help the grasses grow. Processing and bottling the milk also requires water. In total, it takes 880 gallons of water to bring one gallon of milk to your refrigerator.

Most of the water used to produce wine is for growing grapes. When added to the amount of water for bottling, it totals 1,008 gallons of water to produce one gallon of wine.

The term “water footprint” is the term used to describe the total volume of freshwater consumed to produce a good or service.

Answer: a gallon of wine has a larger water footprint than a gallon of milk.

Source: National Geographic / Water Footprint Network

What has a greater water footprint: one egg or one slice of bread?

One egg

A slice of bread takes about 11 gallons of water, most of it for growing wheat. Each pound of chicken requires 2 pounds of grain for feed and the associated irrigation. Ultimately, each egg requires 53 gallons of water.

More comparisons:

1 pound of rice requires 449 gallons of water
1 pound of potato requires 119 gallons of water

1 pound of chicken requires 468 gallons of water
1 pound of beef requires 1,799 gallons of water

1 gallon of coffee requires 880 gallons of water
1 gallon of tea requires 128 gallons of water

Source: National Geographic / Water Footprint Network

What accounts for the vast majority of world water use?

  • a) industry
  • b) farming and ranching
  • c) drinking water
  • d) electricity generation

b, Farming and ranching

Farming and ranching currently account for 64% of all water use worldwide. Without irrigation, it would not be possible to grow crops in areas with low rainfall. Irrigation helps grow 40 percent of the world’s food and makes it possible to feed the planets 6.8 billion people.

When we use water in our homes or industries use water in their businesses, about 90% of it is returned back to streams or into the ground where it can be used for other purposes. With irrigation, only about half the water is reusable. Why?

Because of evaporation and transpiration

Evaporation is the process by which a water molecule is converted from its liquid form into a vapor form. When water is sprayed on crops only about half of it is reusable. The “lost” water is evaporated into the air, transpired through the plants, or lost along the way, by a leaky pipe, for example.

Three factors affect water evaporation:

  • The temperature and humidity of the surrounding air: the warmer and drier the climate, the faster the evaporation.
  • How long it takes the droplet to get to the ground: water sprayed at greater heights and over greater distances gives greater opportunity for evaporation to occur.
  • The surface area of the droplets: the smaller the droplet, the easier it is to evaporate.
Source: The United States Water Science School

How much water does it take to make a plastic 1-liter bottle of water?

2 liters

The environmental and economic costs of bottling and delivering bottled water to consumers are a growing concern as the market continues to expand. Water is mostly bottled in plastic containers that need to be produced, then filled, transported, and refrigerated before it reaches the consumer.

It is estimated that this process takes three liters of water to produce one liter of bottled water. It takes twice as much water to make the bottle as to put into the bottle.

Source: The Pacific Institute

How much oil does it take to make one plastic water bottle?

Because plastic bottles are cheap, accessible, and lightweight, they are ideal for bottling and transporting liquids. Most water is sold in bottles made from polyethylene terephtalate (PET) plastic. PET plastic is created by mixing hydrocarbons extracted from crude oil with chemical catalysts, triggering polymerization.

After the bottle is produced, it is transported by truck, train, air, or ship to the user where it is refrigerated. A bottle filled ¼ with oil would represent the amount of petroleum used in the production and transportation of that bottle of water. After the bottle is produced, it is transported by truck, train, air, or ship to the user where it is refrigerated.

Source: The Pacific Institute

Cities are generally hotter than their surrounding areas. What is this phenomenon called?

Urban heat island

“Heat island” is a term that describes built up areas that are hotter than nearby rural areas. A city with 1 million people or more can be 1.8° – 5.4° warmer than its surroundings. As urban areas grow, buildings, roads, and infrastructure replace open land and vegetation. Surfaces that were one permeable and moist become impermeable and dry.

On a hot sunny day, the sun heats up exposed surfaces such as roofs and pavements to temperatures 50° – 90° hotter than the air. Atmospheric heat islands become hotter than their surroundings after the sun has set when the heat is slowly released from urban infrastructure.

At night, the difference in temperature between an urban heat island and its surroundings can be as high as 22°.

Source: EPA

Cities are looking for ways to become cooler, wetter, and greener. Last year, the City of Philadelphia overhauled the 800 block of Percy Street in South Philadelphia. What is so special about Percy Street’s street?

It has a porous pavement.

The conventional impervious asphalt on the 800 block of Percy Street in South Philadelphia was replaced by a porous, sponge-like substitute. Porous asphalt is as strong as conventional asphalt and looks almost identical but includes voids and spaces to allow water to pass through it. A stone layer beneath the street provides temporary storage until it can soak into the ground.

Philadelphia has a combined sewer system that includes a storm-water system and a sanitary system to handle water from showers, sinks, and toilets. During heavy rainfall, water treatment facilities divert excess incoming water into local rivers. On Percy Street, storm water that would normally overwhelm the gutters and the water system is diverted into the ground. The porous green street pilot program in South Philly represent a collaboration between the Philadelphia Water Department and the Philadelphia Streets Department.

Source: Philadelphia Water Department

What are the three types of “fuel” that the human body needs to sustain life?

Fats, proteins, and carbohydrates

In the animal kingdom, fuel is provided by the breakdown of foods. Fats, protein, and carbohydrates are digested in the intestines and broken into their basic units.

Fats convert to fatty acids and glycerol; proteins convert to amino acids; carbohydrates convert to sugar. All three provide energy to the body.

What is the breakdown of food and the conversion to energy called?

Metabolism

The word metabolism comes from the Greek words meta and ballein, meaning “to throw”. Metabolism refers to the chemical changes that “throw into a different position” or convert energy in living tissues.

What is the type of metabolic fuel that the brain uses under most conditions?

Glucose

Unlike most other organs in the human body, the brain is active at all times and needs to be constantly fed. When one eats, sugar from ingested food enters the digestive tract and from there goes into the blood stream. Circulating blood delivers sugar in the form of glucose to the brain, which it converts into energy. Glucose is of central importance in the chemistry of life, especially for the brain.

Where does the brain get its fuel after glucose has been depleted from the blood stream?

From a stored type of sugar called glycogen

When sugar in the blood stream enters the liver, it is converted into glycogen. In animals, glycogen is stored mainly in the liver and muscle cells. In time, when glucose is depleted, the glycogen breaks down, glucose is liberated, and delivered to the brain through the circulation of blood. Glycogen stores can be replenished by the consumption of food. If not fed, it will take the liver 6-8 hours to exhaust its supply of glycogen.

Where does the brain get its fuel after glucose and glycogen are depleted?

From amino acids in muscle proteins and several other small molecules

In 6-8 hours, when the supply of glycogen runs out, the liver begins to break down muscle proteins and use the amino acids to make glucose.

Where does the brain get its source of energy after glucose, glycogen, and muscle proteins run out and the body is starving?

From ketoacids, made from fat

The brain relies on the stomach and the intestines for sugar immediately after eating. For intermediate times, stored glycogen in the liver is converted to glucose to feed the brain. For longer stretches of time, the liver uses amino acids from proteins to make new glucose for the brain. During starvation, fat is broken down and liver makes ketoacids that can be used to fuel the body.

Fats, proteins, and carbohydrates differ in how quickly they provide energy to the body.

Carbohydrates are the quickest and fats are the slowest.

What part of your body controls your metabolism?

Your brain, especially the brain’s hypothalamus and pituitary glands working together

The hypothalamus receives information from nerves throughout the body and initiates signals in response to shifting environmental and developmental conditions. The “signals” are hormones – chemicals that travel throughout our body, either into neighboring tissue or into our blood stream. They regulate the activity of their target cells or organs.

Hormone signals from the hypothalamus regulate the pituitary gland, which is sometimes referred to as the “master gland” because it in turn directs other glands to suppress or induce hormone production.

The pituitary gland is pea-sized gland located at the base of the skull between the optic nerves, just under the hypothalamus. The hypothalamus and the pituitary gland working together act as a thermostat, controlling many bodily functions including childhood growth, testosterone and estrogen production, body temperature, and urine production.

What is the difference between a gland and an organ?

An organ is a collection of different types of tissue that are joined together to perform a specific function. For example, the heart is an organ. It is made up of myocardium, nerves, blood vessels, and connective tissue that all work together to keep blood circulating through the body.

A gland is an organ that secretes important bio-substances. The pancreas is a gland that releases two key hormones: insulin and glucogon. Salivary glands produce enzymes to break down food. Mammary glands secrete milk.

True or False: In general, the more muscle and less fat you have, the higher your metabolic rate.

True

“Metabolism” refers to your body’s system for using or converting energy. This includes breathing, digestion, building of muscle, storage of fat, and circulation of blood.

The “metabolic rate” is the sum of all these energy-requiring biochemical reactions occurring over an interval of time. Your metabolic rate is strongly influenced by your body composition. People with more muscle and less fat generally have a faster metabolic rate.

True or false: Women usually have a higher metabolic rate than men.

False

Women have higher levels of fat tissue, which lowers their metabolic rate.

True or False: Caffeine can boost your metabolic rate.

True

Caffeine is a stimulant and can boost your metabolic rate for a short period of time. This is why
caffeine is often an ingredient in weight loss diet supplements.

True or false: Most of the calories that your body uses are burned during physical exercise.

False

On the average, 600 – 1,000 calories are burned daily maintaining your body’s vital processes: breathing, digesting food, storing fat, circulating blood, and building muscle. With moderate exercise, an additional ~1000 calories are used in a day. Therefore, half the calories are used for physical exertion and half are used for maintaining your living being. In contrast, cross-country skiers use about 6,000 calories a day, both in keeping warm and moving. Most of their calories are burned by muscle.

How many tastes can a human tongue distinguish?

Five

Taste is the ability to respond to dissolved molecules. Humans detect flavor with taste receptor cells, clustered in taste buds on the tongue. We all know that the human tongue responds to flavors that are salty, bitter, sour, and sweet.

In the early 1900s, a Japanese chemist named Kikunae Ikeda realized there was another taste beyond these four when he ate a bowl of seaweed soup. He discovered we have a fifth taste that responds to glutamate and allows us to enjoy savory food. He called it umami, a Japanese word meaning “delicious”.

Umami foods can be described as “brothy” or “meaty”. Glutamate is found in nearly all foods but is especially high in protein foods like meat, fish, and dairy products. It is also present in vegetables like asparagus and tomatoes.

Dr. Ikeda published his finding in 1909 but it was not until 1985 that umami was officially recognized as the fifth basic taste.

Ikeda, K. (1909) New seasonings. J. Tokyo Chem. Soc. 30:820 -836 [in Japanese].

Using the salts found in glutamate, Professor Ikeda patented a food additive to enhance the flavor of umami. What is it?

Monosodium glutamate or MSG

Dr. Ikeda isolated the (mono) sodium salt of glutamic acid from brown kelp and found it imparted a highly desirable flavor when added to other food. In 1908, he submitted a patent for MSG. MSG is a tastant, like salt, and is not to be eaten alone but used to flavor other foods.

Like all other basic tastes, except for sucrose, MSG improves the pleasantness of food only in the right concentration. An excessive amount can be unpleasant. MSG, like Accent™ seasoning, adds the umami taste of glutamate to other foods.

Ikeda K (1908) "A production method of seasoning mainly consists of salt of L-glutamic acid" Japanese Patent 14804..

True or false: Taste receptors are only found on the tongue.

False

Taste receptors do more than just taste in the classical sense. In addition to the tongue, taste receptor cells are found in other parts of the body. They appear to detect chemicals in our internal environment.

Bitter taste receptor cells are found in the cilia and smooth muscle cells of the windpipe, probably to expel inhaled irritants.

Source: Shah, Ben-Shahar, Moninger, Kline, and Welsh (2009) “Motile cilia of human airway epithelia are chemosensory” Science 235 (5944):1131-1134

Taste receptors are also found in the first section of the small intestine. When sugars reach and bind to the receptors, the cells there respond by releasing incretins that cause the beta cells in the pancreas to increase their release of insulin.Taste receptors are also found in the insulin-producing pancreatic b cells and may directly augment insulin secretions caused by glucose.

True or false: Each taste – bitter, umami, etc – is only tasted on certain regions of the tongue.

False

In the past it has been reported that certain areas of the tongue respond to certain tastes and not to others. For example, it was thought that sweetness could only be tasted on the tip of the tongue and bitterness at the back.

In the 1970s, a physiological researcher, Virginia Collings, reexamined the variations in taste perception and found that while there are sensitivities in varying places on the tongue, it made little-to-no practical difference.

Each type of taste receptor can be stimulated by a broad range of chemicals but is most responsive to a particular substance. Complex flavors are perceived when the brain integrates input from many taste receptors

These receptors are spread across the tongue.

Source: Huang AL, et al (2006) The cells and logic for mammalian sour taste detection. Nature. 442(7105):934-938.

The amount of taste buds can vary from person to person. Some people taste more intensely because they have been born with extra taste buds. What are these people called?

Supertasters

As much as a quarter of the population has twice the amount of taste buds than other 75%. The more taste buds you have, the more intensely you perceive taste.

These supertasters could be considered picky eaters but they are living in a world where flavor comes on too strong.

On the flip side, a quarter of the world has fewer taste buds. These people are known as non-tasters. Their taste buds are less discriminating so they can be more adventurous with food that they eat.

The rest of us are medium tasters.

There is one taste that supertasters avoid and is considered the strongest taste. What is it?

Bitterness

It is thought that as humans evolved, flavor played an important role in evolution. Many plants with defensive toxins taste bitter to the mammalian tongue. Thus, humans with heightened bitterness sensitivity could escape death by avoiding these poisons.

Supertasters avoid bitter foods like coffee, Brussels sprouts, and grapefruit juice. To make the flavor more palatable, supertasters will add milk and sugar to coffee, salt to many foods, and avoid spicy food.

Nontasters like their coffee black and their spicy foods with lots of hot pepper.

What simple action could be described as a “do-it-yourself” vaccine that prevents the transmission of bacteria and viruses?

Handwashing

Handwashing with soap interrupts the transmission of pathogens that cause disease. Today, diarrheal diseases and respiratory tract infections are the two biggest killers of children throughout the world.

People worldwide rinse their hands with water in the common belief that water alone suffices to clean hands because it removes visible dirt. Water in combination with soap is a much more effective way to remove germs.

Scientific research shows handwashing with soap prevents disease in a more straightforward and cost-effective way than a single vaccine or medical intervention. Better hygiene practices could reduce deaths worldwide, especially in children under 5 years of age.

Source: Global Handwashing.org

What fruit is naturally radioactive due to its relative high levels of potassium?

Bananas

Bananas are rich in potassium and therefore contain a small amount of potassium-40 (K-40), a radioactive isotope of potassium. Radioactive K-40 has an isotopic abundance of 0.01% and a half-life of 1.25 billion years. The average banana contains around 450 mg of potassium and will experience about 14 decays each second.

We live in a radioactive world. Potassium (along with some other radioactive elements) is present in the earth’s crust, oceans, and all organic matter.

We are all, in fact, radioactive. Our bodies contain a lot of potassium because it is an essential element for our body’s growth and maintenance.

Other (mildly) radioactive foods include potatoes, sunflower seeds, nuts, and kidney beans.

True or false: Bananas grow on trees

False

The banana plant is the largest herbaceous flowering plant. They are tall and sturdy and often mistaken for trees.

Bananas are actually berries. A berry is a simple fruit having seeds and pulp produced from a single ovary. In cultivated varieties of bananas, the seeds are diminished nearly to non-existence. The remnants are the tiny black specks in the interior of the fruit.

What is a cluster of bananas called?

A hand

A bunch of bananas is called a hand. A single banana is referred to as a finger. The word banana may have come from the Arab word “banan” meaning finger.

What is banana's starchy cousin called?

Plantain

Because they are soft and sweet, the bananas we eat are referred to as “dessert bananas”. The firmer, starchier fruit are plantains or “cooking bananas”. There is no formal botanical distinction between the two. They are in the genus Musa in the Musaceae family. The major difference between them is usage.

Plantains are usually treated as a vegetable. Because of their firm texture and high starch content, they cannot be eaten raw. They must be cooked. Green plantains resemble potatoes in flavor.

Bananas are smaller and have a thinner skin than plantains. As bananas ripen, the starch in the fruit turns to sugar. The riper the banana, the sweeter it will taste. We can eat bananas raw or cook with them.

Bananas are picked green and later sprayed to promote ripening. What type of gas is used to ripen bananas?

Ethylene

Ethylene is a small hydrocarbon gas. It is a naturally-occurring plant hormone that may also be manufactured. Ethylene is responsible for the changes in texture, softening, and color involved in ripening.

Bananas are picked before they are ripe and then carefully transported in refrigerated shipping for 3-4 weeks. Once in their destination country, they are put in rooms filled with low concentrations of ethylene gas to induce ripening.

Bananas can be ordered “ungassed” and show up at the supermarket fully green. Green bananas that have not been gassed will never fully ripen before rotting.

How many varieties of bananas are there?

  • a) under 5
  • b) 5-25
  • c) 26-200
  • d) over 1000

a) Over a thousand

Although there are over a thousand varieties of bananas, we usually see just one type in our supermarkets, the Cavendish. This decision is mostly economic, banana growers and shippers use just one type of banana to ensure that all fruit in one shipment ripens at the same rate.

Bananas were first domesticated in Southeast Asia. They were officially introduced to the American public at the 1876 Philadelphia Centennial Exhibition. Each banana was wrapped in foil and sold for ten cents. Before that time, sailors would bring them home to United States after traveling in the Caribbean.

Bananas are available all year round. They are harvested every day. They have no fat, cholesterol, or sodium. They are an excellent source of vitamins B6 and C, dietary fiber, and potassium.

Did dinosaurs eat grass?

Yes. Well, at least a few of them did.

In the history of the Earth, grass is a relative newcomer but then again, so are dinosaurs. It has long been thought that grass evolved after the extinction events that ended the age of the dinosaurs and closed the Cretaceous Era.

Grass is notable in two aspects: the unique structure of its pollen and the silica that fills its leaves. The earliest evidence of pollen in the fossil record was found in South America and in Africa and was dated to 60 – 55 million years ago, the start of the Paleogene Period.

In 2005, a paper published in Science reported on tiny silica crystals found in fossilized dinosaur dung discovered in central India that was identified as remnants of grass. The researchers believe that the massive, plant-eating reptiles called titanosaurs had eaten grass in addition to their usual diet of flowering plants and conifers.

This finding suggests that grasses evolved earlier than previously thought, maybe 100 – 70 million years ago, just as dinosaurs were leaving.

Source: Prasad, et al (2005) Dinosaur coprolites and the early evolution of grasses and grazers. Science 310:1177-1180.

Which of these plants are grasses?

  • a) wheat
  • b) rice
  • c) sugar cane
  • d) corn
  • e) rye
  • f) oats
  • g) barley

All of them

We could not live without grasses. It forms a major part of our diet and the diet of the animals we eat.

Grass is a graminoid, a family of herbaceous plants. They have narrow leaves growing out of their base. The active growing region of the plant is at the base of the leaf so it survives mowing and grazing. The leaves stand almost vertical, a trait that reduces evaporation.

Grasses spread their pollen by wind so are not dependent on bees or any other insects for survival. Grasses grow fast and can easily colonize patches of ground.

What do we call grasslands in the United States?

Prairies

Grasslands are found where there is not enough rainfall to support a forest but not little enough to form a desert. They are typically flat areas found between forests and deserts.

In South America, grasslands are called Pampas. On the Eurasian continent they are called steppes. In Africa they are savannas and in North America we call them prairies.

All continents have grasslands with the exception of one. Which continent has no grasslands?

Antarctica

Grass is one of the most versatile of life forms and the most-wide spread plant type. It easily adapts to different conditions. Grass can grow in lush rain forests, dry deserts, and cold mountains. About 25% of the Earth’s land mass is covered with grass.

The climate of Antarctica is too harsh to sustain large areas of grasslands but as the environment warms, areas normally covered by ice and snow are being uncovered for longer amounts of time during the year. Tuffs of grass are now being seen in Antarctica for the first time in thousands of years.

What the worst man-made ecological disaster in American History?

The Dust Bowl

Around the turn of the 20th century, a large portion of grassland in the midwestern United States was converted to farmland. Tall grasses that held the topsoil in place for thousands of years was torn up and replaced by fields of wheat. By the late 1920s, the newly available mechanized equipment helped farmers overplow large areas of land very quickly.

In the early 1930s, the rain stopped falling. The drought and heat burned up what plant life existed and exposed the bare ground. The wind swept over the surface of the land and blew great clouds of dust into the air creating “black blizzards”.

The dust choked the residents and livestock and almost brought farming to an end.

How long did the Dust Bowl last?

A decade.

The rain stopped falling on the Midwestern and Southern plains of the United States in 1931.

The area affected during this drought was centered in the Oklahoma panhandle. This part of the country was known for cyclical droughts. The only plant life that naturally flourished there was grass. Poor farming techniques and unreasonable expectations of land combined for the worst man-made disaster in U.S. history.

The Dust Bowl brought ecological and environmental destruction to the America while it suffered through the Great Depression of the 1930s.

Rain finally returned in the fall of 1939.

Several dust storms were so strong, soil blew all the way to the East Coast, over cities and towns, and out into the Atlantic Ocean. The most severe storm was recorded on April 14, 1935. What was this day called?

Black Sunday

On April 14, 1935 a particularly severe dust storm moved across the midwestern prairie displacing an estimated 300 million tons of topsoil. It moved eastward across the United States.

In Washington, Hugh Bennett, a soil expert in the Department of the Interior, had been lobbying congress to enact a permanent well-funded agency to help heal the land. His stance was controversial. Many legislators believed that this land could not be rehabilitated but Bennett insisted that better farming practices could save this area. Crops could be rotated, land could be left fallow, and grass could be replanted.

While presenting his case to Congress on Friday, April 19, 1935, the dust storm blew into Washington five days after beginning in the Midwest. “This, gentlemen, is what I am talking about,” said Bennett. “There goes Oklahoma.”

Within a day, a permanent agency was established and the Soil Conservation Act was signed by President Franklin Roosevelt shortly thereafter.

What landmark piece of American literature was based on the experiences of farmers forced off their land during the Dust Bowl?

The Grapes of Wrath

The Grapes of Wrath was written by John Steinbeck and published in 1939. This novel tells the story of the fictional Joad family, tenant farmers who are driven off their land in Oklahoma by the drought and economic hardship in the 1930s. Like many families during the Dust Bowl, the Joads hoped to leave the dirt and bad luck behind them as they migrated to California.

The novel realistically portrays the horrors of the Depression, the Dust Bowl, and the nature of equality in America. Steinbeck received the National Book Award and the Pulitzer Prize for this book, and it was prominently cited when he won a Nobel Prize in 1962.

 

 

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

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