Welcome ~ and a question ~ “[An] important criticism on the results of our teaching frequently made by those who are not biologists at all, is that the apparent subject-matter of an ordinary course in botany or zoology consists of a congeries of facts more or less closely related among themselves, but having no evident connection with the life of man. To these critics it seems that biologists as a class contribute little or nothing out of their store of knowledge to the solution of the manifold problems of human life. Do scientific biologists contribute no more to the progress of human society than, for example, the scientific philologists?” – Henry R. Linville
Using Technologies to Teach Contemporary Issues in Biology Mark Bloom M.Bloom@TCU.edu www.AndrewsInstitute.TCU.edu
Introductions • Who are you? • Where/what do you teach? • What do you hope to get from today?
Code Names for “Class Work” For any written work you do today, I would like you to use a code to maintain confidentiality and anonymity. To get your code use the first three letters of your mother’s name followed by your month/day of birth. For example, my code would be LIN0831
What is Science? fdaaaaaa
Checks Lab Step1. Randomly select 4 checks from your envelope. Look at the checks carefully and decide what type of data these checks give you as the investigator.
Checks Lab Use your handout to begin to form a list of observations and a list of inferences. Inferences begin to “tell the story” suggested by the data. How Confident are You? ___%
Checks Lab Step 2. Randomly select 4 more checks from your envelope. Continue to construct your story – changing the original idea if you wish. How Confident are You Now? ___%
Checks Lab Step 3. Randomly select 4 more checks from your envelope. Continue to construct your story. Write your story on your paper and post it for others to read. How Confident are You Now? ___%
Checks Lab Step 4. Share your stories with the rest of the groups. Other groups, if you have find a “problem” with the story being presented, let us know. What information did another group have that you did not have?
Checks Lab • Your story may differ due to: • the order you received the checks • your personal bias • your prior knowledge • information you did NOT have
Checks Lab How is the Check Lab similar to the way science works? Give an example of science working in a similar manner to this lab.
What is Nature of Science? • The epistemology and sociology of science • Science as a way of knowing • The values and beliefs inherent to scientific knowledge and its development Lederman, 1992
Tenets of NOS Tentative Empirical Subjective Creative Socially & Culturally Embedded Observations & Inferences Theories & Laws
Tentative Scientific knowledge changes in two ways; it grows as new knowledge is discovered and improves as old knowledge is revised corrected. While scientific knowledge is tentative, there is also much reliability in scientific knowledge because of its empirical basis. Ray Drenner - Hg Toxicity in Aquatic Systems
Empirical Scientific knowledge is based on observations of the natural world. Although all scientific knowledge is based upon empirical evidence, much scientific knowledge (inferences & theories) lacks hard data directly accessible to the senses. Archaeopteryx Pangaea
Subjectivity Scientists’ theoretical commitments and expectations influence their work. Scientists’ observations acquire meaning in reference to questions or problems. These questions or problems, in turn, are derived from certain theoretical perspectives (theory-laden). H. Pylori Drs. Barry Marshall & Robin Warren
Creative Scientific knowledge involves human imagination and creativity. Science involves the invention of explanations and this requires a great deal of creativity by scientists. Dr. Bonnie Bassler
Social and Cultural Science is practiced in the context of a larger culture and scientists are the product of that culture. Science is affected by the various elements of the culture in which it is embedded. These elements include social fabric, power structures, politics, socioeconomic factors, philosophy, and religion. Stem Cell Research & HPV Vaccine
Observations and Inferences Observations are descriptive statements about natural phenomena that are “directly” accessible to the senses. By contrast, inferences are statements about phenomena that are not “directly” accessible to the senses. Charles Darwin And “his” finches
Theories and Laws Theories and laws are different kinds of knowledge; one can not develop or be transformed into the other. Laws are statements or descriptions of the relationships among observable phenomena (the “what”). Theories, by contrast, are inferred explanations for observable phenomena (the “how”).
Contemporary Developments in DNA Technology Read the two short articles before continuing What questions do these articles raise?
DNA is the recipe for Life THE BIG PICTURE Each person has a unique complement of DNA Each person to have a unique complement of proteins Each person having a unique appearance and behavior which causes which contributes to
In humans, our DNA is arranged in the form of 46 Chromosomes Each Chromosome is the equivalent of a cookbook containing recipes for making proteins
Life Cycle of Humans Based on: Mader, S. Inquiry Into Life, McGraw-Hill
Just as a;Cookbookis made of Paper& contains Recipesmade up of Words …aChromosome is made of DNA & contains Genes made up of Nucleotides
Humans may be made of millions of different types of proteins • Functions of Protein • Structural • muscle, hair, nails • Pigment • Melanin • Carotene • hemoglobin • Chemical • Antibodies • hormones • enzymes
What are proteins made of? Proteins are chains of amino acids, usually a few hundred amino acids long AA AA AA AA AA AA AA AA AA AA AA
Protein structure is more than just a chain of amino acids Based on: Mader, S. Inquiry Into Life, McGraw-Hill
Amino Acid Sequence of Hemoglobin Normal hemoglobin Sickle-cell hemoglobin Box shows the one amino acid difference in normal versus sickle-cell hemoglobin
Just like a mutation in the Genecauses the wrong amino acid to be used in creating the protein …a misspelling in the recipe causes the wrong ingredient to be used in creating the casserole
Red Blood Cells Based on: Harvard Family Health Guide, 1999
DNA Control of Protein Synthesis DNA uncoils and one strand is used to produce messenger RNA (mRNA) in nucleus mRNA leaves the nucleus and goes to the ribosomes with copy of blueprint at the ribosomes, amino acids are linked together as specified by the nucleotide sequence of the mRNA
DNA as a Recipe Recipe Books are housed in the Library of the house and cannot be taken to the kitchen – the recipe books have all the recipes for all the “dishes” that can be made in the body Kitchen Workers make a copy of the recipe they wish to make and take the copy to the kitchen Chefs assemble the “dish” out of ingredients like eggs and milk
Human Genome Project • The project began in the late 1980s • supported by 15 billion dollars • Goal of the project was to sequence the • roughly 3 billion chemical letters in DNA • that comprise the genetic code of humans • Many scientists said it could not be done • Project was completed in 2000 • - or was it?
What We Don’t Know about DNA • The sequence of letters in DNA for the human genome is known, but the gene-protein relationships are unknown • It is like having the numbers in a phone book without the associated names • We are learning the identity of new genes each day
Human Proteome Research • Scientists will take decades to • figure out which proteins go with • which genes • All of today’s medicine will seem • medieval once proteomics studies • begin to link proteins and genes • because many human diseases are • genetically based
Tour of the Basicshttp://learn.genetics.utah.edu/content/begin/tour/
Gene Therapies • About 4,000 human diseases are thought to be inherited • Scientists are making good progress figuring out where genes are located on chromosomes and in understanding how the mutations in genes cause disease
Genetic map of chromosome 17 Based on: Mader, S., Inquiry Into Life, McGraw-Hill
Genetic Testing • Now have DNA tests for 30 - 40 diseases • Cystic fibrosis, some forms of breast cancer, fragile X syndrome, Huntington disease, Duchenne muscular dystrophy • Tests are up to 99% accurate • Tests can be run on embryos created by in-vitro fertilization prior to implantation
Future of Genetic Testing When will we have tests for 1000s of genetic diseases in human or what project must be completed for scientists to understand the DNA-protein relationships that cause many human diseases?
Issues about Genetic Testing • What if the news is bad? Should the fetus be aborted or allowed to live with a “cruel” disease? • Should insurance coverage provide care for a child having a genetic disease that was diagnosed before birth? • Should blood relatives be warned? • Should our genetics be part of our records? • Should employers be allowed to consider genetically based diseases in hiring employees? • Will eugenics (manipulation of the hereditary qualities of a race) be practiced?
Gene Therapy • Gene therapy is lagging behind genetic testing • For example, gene for cystic fibrosis was identified in 1989 • Scientists have been testing ways to insert copies of the normal gene into cells of the respiratory tract • It is difficult to get the gene inserted into the tissue so that it can take over control of protein synthesis
Number of approved gene-therapy trials as of 2004 Gene therapy trials are now underway around the world. When will the results be considered part of world knowledge?
www.pbs.org/wgbh/nova/sciencenow/3210/02.html RNAi Therapy
Transcribe and Translate a Gene http://learn.genetics.utah.edu/content/begin/dna/transcribe/