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The Chemistry (and Meaning) of Life
A Dramatic Introduction
to the Chemistry of Life

(Click here for PDF copy of this)

PREPARATION:
Gather the materials listed below under "SO - What chemicals are we made of?" Arrange them near the front of the room to reveal to class as each chemical (and its proportion in us) is read aloud. Also, bring in a large bucket or tub.

Point out: We will be doing two things at once:
1. Studying an idea about how life might have started [the heterotroph hypothesis] 2. Studying facts about the known chemistry of life

SO - What IS life? [display the Working Definition on handout: Intro to Molecular Biology] “... an organized series of chemical processess...”

SO - What chemicals are we made of?
Read aloud “What are little girls made of?” – showing examples of each item in the list [set these up before class, ready to show as you mention them].

What are little girls made of? Right...’Sugar and spice and everything nice.’ Says the nursery rhyme. Well, there ARE some nice features, alright, and also ...
at least 4 lbs. (1.8kg) of sugar (show a 5-pound bag of sugar), and also...
Enough chlorine to disinfect 5 swimming pools (3-5 gallon jugs of water (labeled ”chlorine”)

* 85 pounds (38.25kg) of oxygen (show demo oxygen bottle)
* 2 ounces (56 g) of salt (salt in salt shaker)
* 50 quarts (50 liters) of water (12 gal.-jugs, or 2 5-gal. carboys of water, or water in aquaria)
* 3 pounds (1.35 kg) of calcium (3 lbs of chalk)
* 24 pounds (10.8 kg) of carbon (24 lbs of charcoal – or 9,000 pencils)
* enough phosphorus to make 20,000 match heads (20 boxes of book matches @ 20 matches/book, and 50 books per box)
* enough fat for ten bars of soap
* enough iron to make a sixpenny nail
* enough sulfur to rid a dog of fleas (flea powder)
* enough glycerin to explode a navy shell (glycerin in bottle)

But.... no spice! (hold up a can of Allspice)

(Taken from the Reader’s Digest)

Additional information:
News article: “The average man’s body has enough carbon for 9,000 lead pencils, enough sulfur to rid a dog of fleas, enough fat to make seven cakes of soap, and enough ireon to make a single fair-sized nail.

AND – What are we worth? (read from articles: once 98 cents, $3.50 in 1972, $5.60 in 1977). NOTE TO TEACHER: These values are ancient! Therefore, you may want to search for and use more recent figures (see links below). Otherwise, remind students that they ARE ancient, and therefore figures are certainly MUCH HIGHER now!

Man’s Worth Rises, Chemically Speaking (San Jose Mercury News, 28 Nov. 1972):
It used to be common knowledge that, from head to toe, the chemical value of the human body was 98 cents. But that ego-deflating figure is increasing, according to Chemical and Engineering News.

CEN reported ... that at current chemical prices, the adult human body is worth $3.50. Biochemist W.D. Noteboom of the University of Missouri at Columbia has even better news. [It was $5.70 in 1977]

Noteboom wrote to CEN to explain that it failed to feed into the computer tabulation of the chemical worth of a human body the value of human serum.

Noteboom said the serum, indispensable in many medical situations, is worth $130 to $170 per liter (1.06 qts). One kind, known as type AB retails f or $270 per liter.

A male adult contains about five liters of blood, source of the precious, life-saving serum. So Noteboom estimates this alone would be worth “an absolute minimum of roughly $650.”

Read from “Six Million Dollar Man”....

The six million-dollar man (Science News, 31 July 1976)
High school science textbooks used to make a big point about the materials that make up the human body only being worth about 97 cents. Yale molecular biologist Harold J. Morowitz finally got fed up with this piece of reductionist nonsense when he was reminded of it again in a birthday card. He got out a biochemical company’s catalog and added up the cost of the synthesized materials, such as hemoglobin ($2.95 a gram and bradykinin ($12,000 a gram), and came up with... guess what? .... A six-million-dollar man ($56,000,015.44) to be exact).

Professor Morowitz’s calculations originally appeared in Hospital Practice and has frequently been reprinted, most recently in the July 19 Washington Post. He uses this public exposure to drive home a more important point, however – that “information is more expensive than matter.” What the biochemical companies offer is simply the highest ‘informational’ (most organized) state of materials commercially available. And even these are mostly taken from living animals; if synthesis of all the compounds offered had been done from basic elements, their cost might be as high as $6 billion.

The logical extreme of the exercise, obviously, is that science is nowhere near getting close to synthesizing a human. Just to take the next step of organization – the organelle level – would cost perhaps $6 trillion. Morowitz thus offers a new dimension to what scientists have been trying to say for the last century: “Dr. Frankenstein was a fraud.”

OUR WORTH TODAY? Here are 5 estimates (click on any of these to see how it was calculated. Googled October 2013):
How Much are the elements of your body worth? (Maybe $5.00?)

What is your body worth? (about $160?)

How Much Are You Worth? (About $1986?)

What is Dollar Value of Human? (EPA: $9.1 million; FDA: $7.9 million; Transportation Dept.: $6 million)

How much is your body worth? ($45 million?)

RECAP 1:
$5? $160? $6 million? $9 million? $45 million???
But...Aren't YOU PRICELESS?

Show big bucket or tub, and ask “What’s the difference between a tub full of all the chemicals found in people, and a living, breathing human being? [Students should say, altogether, “ORGANIZATION!”]

Show the “Powers of 10” film or online slide show. Ask students to notice the different levels of organization, especially in a living organism. [See notes on the”Powers of Ten” below]*

Read the following article:
"A Rather Startling Fact About Stars and Us" (Source Unknown, 1976)

According to Professor Dee Mook of the Dept. of Physics at Dartmouth, each star in the sky is a product of controlled thermonuclear fusion that combines simple atoms to create more complex atoms. The release of energy that follows this fusion of atoms is the source of starlight.

“The physical conditions that exist inside a star are extreme enough to manufacture, by thermonuclear fusion, all the elements in the periodic chart from Hydrogen and Helium up to Iron,” added Mook. “As fusion continues, simple chemical elements become more complicated elements.”

The explosion of the Super Nova returns the complicated atoms of a star to the universe where they can become parts of new stars and be combined with other atoms to create more complex elements.

“The very atoms inside us, except for hydrogen and helium, were formed by stars,” said Mook. “Knowing this, I don’t think that the stars will seem as remote to you as their distances suggests. They are simply your parents.”

Say “We are made of stardust (from 2-3 generations of stars) – may you shine forth forever!”
“You... light up my life.... Be bright! .... Be a star!
Go out and look up at the stars tonight, and shout “Hi Mom! HI Dad! (or whisper it quietly. Some people might wonder about you...).
What IS stardust? [atoms] Atoms of what? What’s an atom?

This is a good time to show the basic structure of an atom (big model or picture): nucleus made of protons and neutrons, with tiny electron particles zooming all around (and even through) the nucleus. Be sure to make clear the fact that the volume of an atom is mostly nothing! Scale analogy: “Visualize this:” If we enlarged an atom to the size of a big baseball stadium, the nucleus would be about the size of a baseball in the center of the field. The protons and neutrons would be about golf-ball size, and the several electrons would be like particles of dust zipping around throughout the stadium. Emphasize the fact that this volume is composed of mostly nothing, and all matter is composed of atoms, so material objects are mostly nothing!

I like to dramatize this by passing a quarter from one hand to the other (illusion), then slamming it down on a student’s desk or table, and “catching” the quarter in my other hand placed under the table – the quarter just passed easily through the emptiness of the solid table. Also fun to repeat this through my head! This is a fairly easy sleight of hand illusion to learn, but practice it well, and don’t tell how it works. There are, or course, strong force fields in an atom that produces the collective sense of solidness, but very little matter.

RECAP 2 and CLOSING REMARKS:
We have seen that we are made of atoms that are mostly nothing, occupy a tiny fraction of space in the universe, and our lives are no more than about 100 years out of the 14 billion year age of our known universe. Yet our atoms are organized in very special ways into complex chemicals that interact in the processes of life. You are priceless. You are made from stardust! You are amazing... and precious to others. You are ALIVE!!!

Alternative closing comments: "For such a tiny speck of material (in this vast universe), existing but an instant in the vastness of time, we (and all life) are very precious...very important, to each other. If you are having problems, trouble, sadness, anger in your life, just stand back and reflect on your place in this universe, and perhaps those problems will not seem so overwhelming!!! In spite of this, even the little things we do can have a profound effect on others, so DO GOOD THINGS!"

Or, you might close with a little homily that, "Even though each of us is just a little speck in the universe, in time and space, we ARE special: we ARE made of stardust...the remains of a supernova, we ARE ALIVE!, we CAN DO amazing things, ...and ALL OF US ARE IMPORTANT, certainly to ourselves, and to those who care about us. Isn't that amazing?!" [From the ENSI Lesson “Time Machine.”]

HANDOUTS:
Hand out the Structure and Changes of Matter / Intro to Molecular Biology (back-to-back) sheet. The first item will provide a general overview and review/reference for students. The second item will provide a graphic organizer for the next concepts to be studied.

*The "Powers of Ten" movie or slide series enables you to move from the familiar to the far reaches of outer space, moving out exponentially, then back down to the familiar, then deep into the microscopic and atomic depths of inner space. This adds further to dramatize the vast ranges of time, size, and space.
Here is an animated "Powers of Ten" site:
*Eames Office Powers of Ten (video) Be sure to expand to full screen.

* A Question of Scale (series of slides)