Name___________________________________
How Expensive are You & Importance of Water Lab
Access the links through Symbiosis online.
Biologically, how much are you worth? The answer to this question varies depending on your
perspective. At the most basic level, 12 elements comprise 99% of the human body—with 95% of the
body composed of the elements oxygen, carbon, hydrogen, and nitrogen.
Purpose
This activity provides an opportunity to contrast the monetary value of the human body at the atomic
and biomolecular levels, and to explain differences in monetary value of the human body with respect
to the characteristics of life. You will compare the role of cellular machinery to laboratory equipment in
the manufacture of biomolecules and apply your understanding of DNA structure to determine the
molecular composition of a given length of DNA. You will also be asked to consider applications of
research in the development of artificial life. Part 2 asks you to become aware of where water exists
around us and how its presence or absence affects all living systems.
Part 1. How Expensive are You?
How much would it cost to purchase the basic building blocks of your body? The elements that make up
the human body can be purchased in purified, laboratory-grade forms from supply companies. These
companies provide the chemicals to research laboratories that manufacture biological molecules.
The current price of these elements for a typical adult is approximately $3,000-$4,000.
However, to make a human body, each of those elements must be chemically bonded to other elements
to produce the complex biological molecules of life (proteins, nucleic acids, carbohydrates, lipids). Using
sophisticated laboratory equipment, highly trained scientists can synthesize these complex biological
molecules from basic elemental building blocks, just like your body does.
The Cost of a Human Body
What is the cost of these biological molecules if purchased in the quantities found in the human body?
Many millions of dollars!
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1. Give your opinion about the value of a human life described here: Environmental
Protection Agency Puts a Value on Human Life.
2. Consider all the life on earth, even invisible life. How much could it all be worth in dollars?
3. At the atomic level human bodies are worth only a fraction of what they are worth at the biomolecular
level. Consider the differences in worth between the elemental and biomolecular components of life.
Explain the difference in terms of the characteristics of life. Use the list of characteristics you textbook
supplies.
4. With respect to the cost of the body at the elemental/molecular level, how do you think can one
increase the value of their body?
5. Manufacturing biological molecules in the laboratory requires the use of relatively pure
laboratory grade chemicals, sophisticated laboratory equipment, highly trained scientists,
and high levels of electricity.
In this table, compare the roles of laboratory components (detailed above) with the cellular components
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DNA, ATP, food and cellular organelles, with respect to the synthesis of biological molecules.
Cellular Component Equivalents (ATP, DNA, etc.)
Lab equipment
Scientists
Electricity
6. Consider an intact length of DNA consisting of 140 total nucleotides (70 nucleotides/strand), with 40
total adenine nitrogen bases. How many of each of the following molecules would be found in the
length?
Nucleic Acid Component
Number in the 140 Nucleotide Strand
Adenine
40
Guanine
____
Thymine
____
Deoxyribose
____
Uracil
____
Phosphate Groups
____
Ribose
____
Cytosine
____
Researchers have reported advances in their attempts to synthesize life from scratch in a test-tube bringing
non-living matter to life. In the lab, they have been able to produce protocells from lipid molecules that
spontaneously trap pieces of nucleic acids possessing the code for replication and metabolism. With continued
progress, protocells may be synthesized that form self-replicating, evolving system that satisfy the conditions
of life. See Scientists Create FIrst Self-replicating Synthetic Life.
Skim the article and view the poll results.
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7. Consider the scientific understanding that may be generated from this project. What scientific questions
might the knowledge generated from this project help answer?
8. Reflect on the broader significance of this work. What objections might be raised about this line of research?
Life expresses emergent properties. Emergent properties are a result of synergistic relationshipsin which the
living system as a whole has more complex or different properties than each element separately. Water
molecules, for example, exhibit several emergent properties that couldn’t be predicted from their atomic
composition (solvency, heat of vaporization, surface tension).
Consider the levels of organization of life: atoms, molecules and macromolecules, cells, tissues, organs and
organ systems, organisms, population, community, ecosystem, biosphere.
9. Identify two examples of emergent properties found in one level that are not found in the previous level.
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Albert Szent-Gyorgyi (1893-1986) was a preeminent biochemist of his time. His work contributed to the
understanding of how muscles work and how the ATP molecule provides energy to fuel a cell’s metabolism. He
won the Nobel Prize in Physiology or Medicine for discovering Vitamin C. In an interview with the BBC in 1965,
Szent –Gyorgyi offered the following about his work:
I started with anatomy, but then shifted to function and physiology studying rabbits.
But then I found rabbits too complicated and shifted to bacteriology, hoping to find the
secrets of life in those very small, tiny creatures. But later I found bacteria too
complicated and shifted to molecules and began to study chemistry—a few years later
after the war I was even condemned to be the Professor of Chemistry and taught
chemistry for many years! About 15 years ago I found molecules too complex and then I
shifted to electrons and quantum mechanics—the behavior of electrons. So I went
through the whole gambit of organization, which was a vain effort, because I ended
with electrons, which have no life at all…molecules have no life—so life ran out between
my fingers.
10. Explain what you think is the main point of Szent-Gyorgyi’s comments.
Part 2. The Importance of Water
Purpose
To become aware of where water exists around us and how its presence or absence affects living systems,
including humans.
Water and Human Health
Water is a nutrient essential to life. Your body is almost three quarters water and water plays several crucial
functions that allow your body to function. To maintain adequate levels of water, it is important you drink
several cups daily. In addition to water taken in the form of beverages, a significant amount of water comes
from the foods you eat.
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Digestion and Transport
The chemical processes that break down protein and carbohydrates in the stomach require water. Digestion
begins in your mouth with saliva, which is primarily water.
5. What are two more uses for water in digestion or transport?
Temperature Control
Water is a good medium for regulating temperature. The evaporation of sweat helps cool the surface of the skin.
5. What are two more uses for water in temperature control?
Protection and Lubrication
Another crucial role water plays in the body is providing structure that protects vital organs. Your eyes, brain
and spinal cord all sit in a protective fluid layer made mostly of water. Without this fluid barrier, minor bumps
and shakes would cause structural damage to these delicate and sensitive organs and tissues. Think of water as
your body's natural lubricant.
5. What are two more uses for water in protection and lubrication?
Dehydration
If you go too long without adequate hydration, you will soon suffer loss of motor function and cognitive skills.
The conditions will worsen until unconsciousness and ultimately death result. Without water, you would die
within three days under normal conditions. Dehydration begins with an imbalance in your bodily fluids. If left
untreated, this condition can continue to worsen. Light to moderate dehydration can cause a lack of saliva, urine
discoloration, less urine, dry eyes and a rapid heartbeat. Severe dehydration can lead to nausea, vomiting and a
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drop in blood pressure that is the result of dehydration shock. If you are beginning to experience signs of
dehydration such as thirst, fatigue, diarrhea or excessive vomiting, consult your physician immediately.
4. Pick three of the symptoms of dehydration. Why, on the cellular level, does dehydration cause these
symptoms?
How You Lose Water
How much water your body needs and how much water you lose can be influenced by several factors. Water is
lost through basic bodily functions like sweating, urination, elimination and breathing. Exercise, environment,
illness and pregnancy can all cause you to lose more water. You should not aim to prevent water loss, but rather
you should try to stay hydrated throughout your day.
Getting Enough Water
Because the amount of water necessary varies for each person's size, lifestyle and physical activity, there is no
single recommended daily intake level for water. It is recommended an average adult drink at least six to eight
cups each day. According to the U.S. Department of Agriculture, average adults take in between nine and 13
cups of water each day including all types of beverages. About 80 percent of total water intake comes in the
form of beverages; water in food comprises about 19 percent.
Water and the Environment
Wetlands
Globally, wetlands cover at least 6% of the Earth’s terrestrial surface. Common inland and coastal wetlands
comprise lakes, rivers, marshlands, mangroves, estuaries and lagoons, groundwater and shallow water coral
reefs and sea grass beds. These ecosystems host a wealth of biodiversity and account for about 45% of the total
value of all global ecosystem services, including those supporting food security and reducing rural poverty. Their
supply of freshwater to human populations is recognized as one of the foremost natural benefits.
Simultaneously, fisheries and aquaculture provide highly valuable food. For instance in the Mississippi Delta, the
value of food production per hectare (10,000 square meters) of wetland is estimated at 1.7 times to almost 40
times that of agricultural land!
Other important functions of wetlands include flow release in dry seasons and their role as local and global
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biodiversity ‘hotspots’.
One of the most important roles of wetlands is in the hydrological cycle, where wetlands contribute towards a
complex series of functions, including water storage, flow regulation, water purification and retention of
nutrients, sediments and pollutants.
River floodplains are often regarded as functioning as natural sponges. They expand by absorbing excess water
in time of heavy rain, and they contract as they release water slowly throughout the dry season to maintain
stream flow. Aquatic ecosystems “cleanse” on average 80% of their nitrogen.
Wetland ecosystems support a wide range of biodiversity, including fish, amphibians and insects, and play a
significant role in water bird flyways and the conservation of water bird populations.
Variability and diversity within and among species and habitat is important for supporting resilience.
Wetlands are further threatened by climate variability. The findings of the International Panel on Climate
Change reports confirm that the changing water cycle is central to most of the climate change-related shifts in
ecosystems and human well-being.
5. Name five wetlands within ten miles of where you live.
Water Footprint
The water footprint of an individual, community or business is defined as the total volume of freshwater used to
produce the goods and services consumed by the individual or community or produced by the business. Water
use is measured in water volume consumed (evaporated) and/or polluted per unit of time. The water footprint
concept was introduced in 2002 by A.Y. Hoekstra as an alternative indicator of water use.
The water footprint of an individual refers to the sum of his or her direct (at home) and indirect (used to
produce goods and services) freshwater use.
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The average global water footprint of an individual is 1,385 m3 per year. 
The average consumer in the United States has a water footprint of 2,842 m3 per year.
The average resident in China and India has a water footprint of 1,071 m3 per year.
The average Finnish water footprint is 1,730-m³ water per person per year.
An individual’s daily diet of fruits, vegetables and grains requires more than 1,500 liters (396.3 US gal) of
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water, as compared to 3,400 liters (898.2 US gal) needed for a daily diet rich in animal protein.
Research by the Cranfield University calculated these amounts in the United Kingdom:
1 cup of tea
1 pint of beer
1 glass of wine
1 glass of milk
2.2 lb of beef
2.2 lb of poultry
8.8 oz packet of M&M's
20.3 oz jar of pasta sauce
Pair of Jeans
A cotton shirt
A disposable diaper
A bed sheet
8.6 US gal
2.3 US gal
31.7 US gal
52.8 US gal
3,962.6 US gal
1,585.0 US gal
304.6 US gal
53.4 US gal
850 liters
4,100 liters of water
810 liters of water
9,750 liters of water
6. Calculate your water footprint here and write it below. How do you measure up to Finland?
7. Convert one of the items listed in liters to gallons.
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Sources:
Ecosystems for Water and Food Security. http://www.unep.org/pdf/depi-ecosystems-food-secur.pdf. Accessed
8/24/12.
Livestrong. http://www.livestrong.com/article/127900-water-important-drink. Accessed 8/24/12.
Mayo Clinic. http://MayoClinic.com. Dehydration, January 2011. Accessed 8/24/12.
Mayo Clinic. http://MayoClinic.com. Water: How Much Should You Drink Every Day, April 2010. Accessed
8/24/12.
National Institutes of Health. Water in Diet, August 2009.
USDA: Fluid Guidelines for Americans.
Wikipedia. http://en.wikipedia.org/wiki/Virtual_water. Accessed 8/24/12.
Wikipedia. http://en.wikipedia.org/wiki/Water_footprint. Accessed 8/24/12.
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