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00:00:30 In the vastness of the universe, our home is the planet Earth.

00:00:35 This complex and delicately balanced planet

00:00:39 is the only place in the known universe where life is known to exist.

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00:00:54 What's really happening inside living things that makes them alive?

00:00:59 What's actually going on inside the organs, tissues,

00:01:04 and cells of living creatures that gives them the qualities we call life?

00:01:10 How do the chemicals which make up every part of a living organism

00:01:15 and its environment work together to enable organisms to survive,

00:01:21 develop, and reproduce in almost every environment on the Earth?

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00:01:42 People have been studying living organisms for thousands of years.

00:01:46 During all this time, we've been trying to figure out

00:01:50 exactly what living things are made of and how they work.

00:01:54 We've also been very interested in why they sometimes don't work

00:01:58 since plants, animals, and people are always getting sick or injured.

00:02:04 And we've been searching for a very long time for ways to make them better.

00:02:10 By carefully studying living organisms all the way down to the chemicals

00:02:14 of which they are made, a tremendous amount has been learned

00:02:18 about the chemistry of life.

00:02:21 Today, we're going to take a look at a few of the many important contributions

00:02:26 that people of African heritage have made to this study of chemistry

00:02:30 in the life sciences.

00:02:33 You'll see that African Americans have had a long history of achievement

00:02:37 in this field, beginning thousands of years ago in Africa

00:02:41 and continuing up to the present.

00:02:45 Let's look at Africa first.

00:02:48 Africa is a huge and diverse continent with beautiful landscapes

00:02:53 and exotic wildlife.

00:02:56 But too often, people think of Africa only in terms of its land and animals.

00:03:01 What many people don't realize is that Africa is a very diverse country.

00:03:07 People think of Africa only in terms of its land and animals.

00:03:11 What many people don't realize is that African people throughout history

00:03:16 have formed advanced societies with strong traditions

00:03:19 of developing science and technology.

00:03:23 The Ishongo bone found in Central Africa is evidence that Africans

00:03:27 were using a number or calendar system 8,000 years ago,

00:03:32 long before such a system evolved in other cultures.

00:03:36 Africa also had an advanced medical science.

00:03:40 Records show that ancient Africans used instruments for dissection,

00:03:44 had a detailed understanding of anatomy and embalming,

00:03:48 and practiced methods of treating many sicknesses.

00:03:53 Ancient Africans were also masters of architecture.

00:03:57 The African physician, engineer, and astronomer Mhotep,

00:04:01 who lived almost 5,000 years ago and is considered by many

00:04:05 to be the world's first great physician,

00:04:08 was also the architect of the step pyramid,

00:04:11 the basis for the great pyramids to follow.

00:04:14 As the years went on, new African technologies were developed.

00:04:19 In Tanzania, African people designed furnaces to produce steel 2,000 years ago

00:04:25 and at temperatures that were not achieved in Europe until the mid-1800s.

00:04:30 The building, in the 12th and 13th centuries A.D. of Great Zimbabwe

00:04:35 in Southeast Africa, with its 40-foot walls and cone-shaped towers,

00:04:40 relied on a high level of mathematical, architectural, and other engineering skills.

00:04:47 The traditional practices of many African people are based on scientific knowledge

00:04:52 passed down to them through the ages.

00:04:55 The technical skills of boat building and navigation, agriculture, metalwork,

00:05:02 architecture, and medicine are hundreds, sometimes thousands of years old

00:05:09 and show that science has been an important part of African life

00:05:13 and culture throughout its history.

00:05:26 Our look at some of the African and African-American contributions to chemistry

00:05:32 and the life sciences will begin with traditional African healers.

00:05:37 When you get a stomachache, headache, or sore muscles, is this what you take?

00:05:43 How about this?

00:05:46 Well, believe it or not, these are some of the plants that have been used

00:05:51 in different parts of Africa to treat these problems for centuries.

00:05:56 The plants were used by traditional healers who developed plant medicine

00:06:00 into a real science.

00:06:02 These healers were skilled in diagnosis and had a detailed knowledge of anatomy.

00:06:08 Although they didn't use our modern technical names for the chemical compounds

00:06:12 in the plants they were using, the traditional healer was highly skilled

00:06:17 in identifying, preparing, and using the chemicals from hundreds of these plants

00:06:22 to promote healing.

00:06:25 The Bantu-speaking people of Central Africa used the bark from a type of willow tree

00:06:30 to ease pain in the muscles and bones.

00:06:33 When the chemicals from the bark were analyzed in modern laboratories,

00:06:37 they were found to contain salicylic acid, the active ingredient in today's aspirin.

00:06:44 In Nigeria, for example, certain herbs were mixed and used to treat skin infections.

00:06:51 When the same herbs were tested in laboratories, chemical compounds in the herbs

00:06:56 were found to kill the very type of bacteria known to cause certain skin infections.

00:07:02 In Mali, in West Africa, a mineral called kaolin was extracted from the ground

00:07:08 and used to treat diarrhea.

00:07:10 It was kaolin that was used until 1989 in the diarrhea medicine chaopectate.

00:07:18 The traditional African healers even used a type of vaccine.

00:07:22 In Liberia, a type of smallpox vaccine was in use before it had been developed

00:07:27 and used in Europe.

00:07:30 This long tradition of scientific discovery is carried on by today's African scientists

00:07:36 who continue to explore the chemistry of living organisms

00:07:40 for better ways to treat today's illnesses and diseases.

00:07:48 In the United States, despite a history of slavery, discrimination, and hardship,

00:07:53 dedicated and committed African Americans have made major contributions

00:07:58 to our knowledge of the chemistry of living things.

00:08:07 One scientist who added a tremendous amount to our understanding of living organisms

00:08:13 at the chemical level was Ernest Everett Just.

00:08:17 Just was born in 1883 in Charleston, South Carolina.

00:08:22 These were years after which slavery in the United States had been abolished.

00:08:27 Just's father was a dock worker and his mother a school teacher.

00:08:33 Just was an excellent student and finished first in his high school class

00:08:37 and graduated with the highest honors from Dartmouth College.

00:08:42 During his college years, Just became fascinated by the mysteries of life

00:08:47 hidden in the cell.

00:08:50 Every living thing, including your own body, is composed of cells.

00:08:55 These are blood cells, human nerve cells, and these are bone cells.

00:09:02 Just did his research at the Marine Biological Laboratories in Woods Hole, Massachusetts.

00:09:08 There, Just used marine animals to try to figure out how a single fertilized egg cell

00:09:14 could multiply and change to become all the different parts of a whole organism.

00:09:20 Just challenged the traditional theories of cell development

00:09:24 and showed that chemicals outside the egg cell nucleus

00:09:27 played an important role in cell multiplication and development.

00:09:32 Just's theories, discoveries, and laboratory techniques

00:09:36 revolutionized the study of egg cell development

00:09:39 and helped pave the way for today's research in this important scientific area.

00:09:45 Just won many honors and awards as a scientist and as a professor,

00:09:50 and generations to come will benefit from his important work.

00:09:56 Another scientist who made significant achievements related to chemistry

00:10:00 and the life sciences was a chemist named Percy Julian.

00:10:05 Julian was born in 1899.

00:10:08 His father was a postal clerk and his mother a school teacher.

00:10:12 Julian did well in high school and received a degree in chemistry from DePaul University

00:10:18 with the highest grade point average in his class.

00:10:22 Among his many accomplishments,

00:10:24 Julian successfully produced a chemical compound in the laboratory

00:10:28 to treat the damaging eye condition, glaucoma.

00:10:32 Julian later became chief chemist and director of research at a large chemical company

00:10:37 where he worked with the chemistry of soybeans.

00:10:40 Julian developed a foam from the protein in soybeans

00:10:44 which could be used to put out fires.

00:10:47 This invention, called aerofoam, saved the lives of many soldiers in World War II.

00:10:54 Another of Julian's major breakthroughs was his making of the drug cortisone,

00:10:58 also from the chemicals found in soybeans.

00:11:02 Cortisone has many uses, one of the most important of which

00:11:05 is to relieve the swelling and pain from certain forms of arthritis.

00:11:10 Percy Julian's scientific achievements have helped countless people

00:11:14 lead healthier and happier lives.

00:11:19 Another great African-American scientist working with the chemistry of living organisms

00:11:24 was Charles Drew.

00:11:27 Drew was born in 1904 in Washington, D.C.

00:11:31 He was an excellent student and athlete.

00:11:35 After graduating from Amherst College and McGill Medical School,

00:11:39 Drew worked out the difficult problems of blood chemistry

00:11:43 and succeeded in developing one of the most significant

00:11:46 life-saving medical discoveries of his time,

00:11:49 a way of preserving human blood plasma.

00:11:53 It's the chemicals that make up your blood which carry the life-giving oxygen

00:11:57 and nutrients to all the cells of your body.

00:12:00 And it's because of Charles Drew that blood can be donated

00:12:04 and the plasma stored so that lives can be saved.

00:12:08 Because of Drew's great work, wounded soldiers can be given blood transfusions

00:12:13 on the battlefield or in the hospital,

00:12:16 and preserved plasma can be used during surgery

00:12:19 and for injuries suffered in disasters such as earthquakes or hurricanes.

00:12:25 Because of his knowledge and skill in the preservation of blood plasma,

00:12:29 Drew was appointed the head medical supervisor

00:12:32 of the Blood for Britain program during World War II

00:12:35 and was later made the first director of the American Red Cross Blood Bank.

00:12:40 Charles Drew's accomplishments live on

00:12:43 through the many doctors he trained over the years

00:12:46 and through the lives that are still being saved as a result of his great work.

00:12:51 African-American contributions to chemistry and the life sciences continue today.

00:12:57 Dr. Gerald Stokes, a microbiologist at George Washington University Medical Center,

00:13:03 and Dr. Shiren Hunter, a neurochemist at the National Institutes of Health,

00:13:08 both use chemistry to help solve some important human health problems.

00:13:14 I'm working with a bacteria called Chlamydia.

00:13:17 It causes a number of major diseases in our country,

00:13:20 venereal infections, eye infections, and pneumonia.

00:13:23 My particular work involves trying to understand how these bacteria grow

00:13:28 and how the cells in which they grow support their growth.

00:13:32 Dr. Hunter is working on the challenging problem

00:13:35 of how chemistry is related to human hearing.

00:13:39 I'm working with a chemical called glutamate.

00:13:42 This chemical, along with others,

00:13:44 binds to nerve cells in the human brain that are involved in hearing.

00:13:48 The action of these chemicals on nerve cells in the brain

00:13:51 help people tell the pitch, location, and volume of sounds.

00:13:56 Researchers who study living organisms agree

00:13:59 that an excellent background in chemistry is essential.

00:14:03 Chemistry gives me a fuller appreciation of biological processes.

00:14:08 Without that understanding, my job would be much more difficult.

00:14:12 Chemistry makes the difference.

00:14:14 The bottom line of all living things is chemistry.

00:14:17 It's as simple as that.

00:14:20 Dr. Stokes, Dr. Hunter, and other young scientists

00:14:24 are active in encouraging students to become involved in the sciences.

00:14:29 Right now we have a problem in terms of manpower,

00:14:32 and it's important that more black individuals

00:14:35 take part in science in our country.

00:14:38 Minority students now have a far, far wider choice

00:14:41 of support structures, support organizations, and individuals.

00:14:45 Institutions are eagerly waiting and encouraging them to go on.

00:14:50 These are opportunities that every young man and woman should exploit.

00:14:55 High school seniors Mark Shepard and Gloria Hairston

00:14:59 have taken advantage of these opportunities

00:15:02 to do interesting work in the sciences.

00:15:05 Gloria, who was chosen to compete in a nationwide science project competition,

00:15:11 designed an experiment in her advanced biology class

00:15:15 to test the genetic effects of different concentrations

00:15:18 of a different type of alcohol on fruit flies.

00:15:22 Mark, who participated in a summer science internship program,

00:15:27 worked in a physics laboratory at a local university

00:15:31 where he helped a team of scientists measure the magnetic fields

00:15:35 produced by moving electrons.

00:15:38 Even this magnetic property of chemicals has been applied to biology

00:15:42 in scanning equipment that uses magnetism

00:15:45 to make images of the body's internal organs and other tissues.

00:15:50 Both Gloria and Mark plan to continue their work in science

00:15:54 when they get to college.

00:15:57 You should ask your science teacher about designing a special science project

00:16:01 or working in a university or other research laboratory setting.

00:16:06 There are a lot of opportunities for students interested in science.

00:16:11 But to really succeed in science,

00:16:14 people like Percy Julian, Charles Drew, Ernest Just, and you

00:16:19 need to study hard and enjoy what you learn.

00:16:22 But just as important, your family and friends

00:16:25 need to encourage and support what you're doing.

00:16:28 My parents and my family are my main support system.

00:16:32 At times, when I was going through junior high and high school,

00:16:36 they were my only support system.

00:16:39 Sometimes when your science classes are really difficult

00:16:42 and you might feel like giving up,

00:16:45 look to your family and people you trust for support.

00:16:48 And remember, you come from a long history of mathematicians,

00:16:53 engineers, doctors, and chemists,

00:16:57 and that you have the ability to succeed in the sciences.

00:17:02 If you have the energy, creativity, and commitment,

00:17:06 the world is waiting for your contribution.