From DNA to Protein: The Genetic Code Unveiled

1. From Gene To Protein Transcription Translation Chapter 8 – Section 8.2 Pages 194 – 202 BONUS QUESTION

2. DNA to mRNA (messanger) • DNA A – T and G – C • DNA zips open • Transcription factor “reads” DNA and “writes” mRNA • DNA zips closed • RNA A – U and G – C • Single strand • “Edited” • mRNA enters cytoplasm http://publications.nigms.nih.gov/thenewgenetics/images/ch1_trans.jpg

3. mRNA to rRNA (ribosome) • mRNA leaves nucleus of cell • rRNA large 2 unit macromolecule “builds” proteins from amino acids • Amino acids brought to rRNA by tRNA (transfer) http://publications.nigms.nih.gov/thenewgenetics/images/ch1_trans.jpg

4. mRNA to amino acid • 3 nucleotides (codon) = 1 amino acid • A little math: • 4 nucleotides (AUGC) • Combination of 3 for amino acid • How many combinations of 3 are there? • 64 combinations http://library.thinkquest.org/04apr/00217/images/content/ribosome.jpg

5. Genetic Code • 20 amino acids • 3 “stop” codons • 64 combinations of mRNA • Redundancy • Codon 3 “wobble” • Can mutate with no change in amino acid http://images2.clinicaltools.com/images/gene/codontable2.jpg

6. Amino Acid • Amino Acids can have a charge (positive or negative), hydrophobic or hydrophylic • These interact with other amino acids in the protein strand and the cell (functional groups http://www.langara.bc.ca/biology/mario/Assets/aminoAcidStruc.jpg

7. Amino Acids to Proteins • Amino Acids are strung together • Form a sheet or helix • Fold with other amino acids on the same strand • Can be one protein in a complex of several proteins – part of a final product http://academic.brooklyn.cuny.edu/biology/bio4fv/page/prot_struct-4143.JPG

8. Example – Hemoglobin • Comprised of 4 protein subunits, 2 alpha () and 2 beta (), which form the complex hemoglobin • Each subunit associated with a non-protein heme group http://chemistry.ewu.edu/jcorkill/biochem/HemoglobinMOM.jpg

9. Regulation – cell signaling • Cell receives signal to produce a specific gene • Example – hormones produces in one part of the body and signal another part to function http://219.221.200.61/ywwy/zbsw(E)/pic/ech6-1.jpg

10. Regulation • Our cell uses glactose first • If our cell has lactose and no glucose, genes expressed to break lactose down • When lactose becomes limited or glucose available, gene deactivated http://xanta.com.ne.kr/2008/2008-1/08-1-biochem/08-1-biochem-3-2.gif

11. Introduction to Physiology Cells Tissues Organs Organisms

12. Tissues • 4 major types of tissues: • Epithelial • Connective • Muscle • Nervous http://www.emc.maricopa.edu/faculty/farabee/biobk/stomTS.gif

13. Epithelial • Tightly packed sheets of cells that cover • Outer surfaces – i.e. skin • Lining hollow organs – i.e. blood vessels • Cover organs - i.e. kidneys http://media.wiley.com/Lux/70/21770.nfg001.jpg

14. Connective • Cell plus matrix • Bone • Fat • Blood • Cartilage • Fibrous – ligaments and tendons • Loose – links different tissues together http://media.wiley.com/Lux/73/21773.nfg004.jpg

15. Muscle • Striated or Skeletal • Attached to tendons which attach to bone • Voluntary movement • Smooth • Peristolic slow undulating contractions • Involuntary movement • Cardiac • Heart http://www.agen.ufl.edu/~chyn/age2062/lect/lect_19/146.gif

16. Nerve • Single cell type • Can be extremely long (from toe to spine) • Cells divide until a certain point in fetal development, then never divide again http://www.botany.uwc.ac.za/sci_Ed/grade10/mammal/images/neuron.gif

17. Organs • Composed of at least two types of tissues which work together for a specific function • Heart contains all 4 tissue types to pump deoxygenated blood to the lungs and oxygenated blood to the body http://www.niaaa.nih.gov/NR/rdonlyres/FD5DD30B-F412-46BF-B407-5421CBD0C8DB/0/271f2.gif

18. Organ Systems • Digestive • Excretory • Cardiovascular • Muscle/Skeletal • Integument • Endocrine • Nervous • Lymphatic • Reproductive http://www.rogers.k12.ar.us/users/ehutches/Image567.gif

19. Homeostasis • Negative feedback • Body temperature • Blood pH • Blood glucose levels • Most other functions • Positive feedback • Menstruation • LAC operon • Lactation http://academic.kellogg.cc.mi.us/herbrandsonc/bio201_McKinley/f20-2b_positive_feedbac_c.jpg http://academic.kellogg.cc.mi.us/herbrandsonc/bio201_McKinley/f20-2a_negative_feedbac_c.jpg

20. Cardio-pulmonary System • Due to time limitation of this class, we will use cardiovascular and pulmonary systems as an example of organ system • As a teacher, you can use each organ system to exemplify: • Organisms • Describe the function of organ systems • Classify organs by the system to which they belong http://www.dorlingkindersley-uk.co.uk/static/clipart/uk/dk/exp_humanbody/exp_human055.jpg

21. Cardiovascular System • Lungs • Gas exchange • O2 in • CO2 out • Heart and vessels • Pumps blood to lungs for oxygen • Pumps blood to body to deliver O2 and pick up CO2 http://academic.kellogg.cc.mi.us/herbrandsonc/bio201_McKinley/f22-1_cardiovascular_sy_c.jpg

22. Lungs - Mammals • Tidal Volume • Oxygen inhaled • Carbon Dioxide exhaled • Air into trachea, bronchus, bronchi, bronchioles, alveoli (smaller and smaller tubes http://www.odec.ca/projects/2005/thog5n0/public_html/lungs.jpeg

23. Alveoli • Tiny air sacs • Highly vascularized with capillaries • Surface area for gas exchange O2 uptake Alveoli CO2 output http://www.3dscience.com/img/Products/3D_Models/Human_Anatomy/Alveoli/supporting_images/3D_Model_Anat_Alveoli3_web.jpg

24. Heart • Deoxygenated Blood • Enters via anterior and posterior vena cava to right atrium • Enters right ventricle through the atrioventricular valve which stops blood returning to right atrium http://www.vaughns-1-pagers.com/medicine/heart-diagram3.gif http://www.heart-health-weightwatcher.com/images/HumanHeartDiagram.jpg

25. Heart • Right ventricle through the pulmonary semilunar valve to the lungs via pulmonary arteries • Blood blows off carbon dioxide and uptakes oxygen in capillaries of alveoli of lungs http://www.vaughns-1-pagers.com/medicine/heart-diagram3.gif http://www.heart-health-weightwatcher.com/images/HumanHeartDiagram.jpg

26. Heart • From the lungs through the pulmonary veins, blood enters the left atrium • Blood enters the left ventricle through the left atrioventricular valve http://www.vaughns-1-pagers.com/medicine/heart-diagram3.gif http://www.heart-health-weightwatcher.com/images/HumanHeartDiagram.jpg

27. Heart • Blood is pumped through the aorta to the brain, arms and lower body by the left ventricle • Coordination of the cardiac contractions by heart’s pacemaker – sinoatrial node http://www.vaughns-1-pagers.com/medicine/heart-diagram3.gif http://www.heart-health-weightwatcher.com/images/HumanHeartDiagram.jpg

28. Circulatory System • From the heart, blood enters arteries to arterioles to capillaries • Single blood cells pass through capillaries releasing oxygen and uptake carbon dioxide • Blood is returned via venioles to veins http://www.unm.edu/~jimmy/vessels.jpg

29. Circulatory System • High pressure: • Aorta to Arteries • Arteries to Arterioles • Arterioles to Capillaries • Capillaries – no pressure http://www.cartage.org.lb/en/themes/sciences/lifescience/generalbiology/Physiology/CirculatorySystem/CirculatorySystem/Vertebrate/bloodvessels_3.gif

30. Capillaries • Network of tiny vessels – leaky • Like a river delta, all pressure from river behind it drops and water oozes to ocean • Once blood cell at a time • Circulation http://www.shockwavetherapy.ca/capillaries.jpg

31. Circulatory System • Starts with no pressure to return blood • Capillaries to venuoles • Venuoles to Veins • Veins to Anterior and Posterior Vena Cava • How does that work? http://www.cartage.org.lb/en/themes/sciences/lifescience/generalbiology/Physiology/CirculatorySystem/CirculatorySystem/Vertebrate/bloodvessels_3.gif

32. Veins • Veins have valves to stop blood flowing backwards • Muscle action accounts for most of the return of blood to heart • Volume decreased because some plasma enters lymph system and is returned to heart to mix with returning blood http://www.originmedical.co.uk/client_files/leg_illustrations/NormalVeins-All.jpg

33. Invertebrate Cardiovascular • Insects have an open circulatory system, and oxygen bathes most cells in the body • Oxygen enters through spiracles and travels down trachea • Movement pushes air in and out http://io.uwinnipeg.ca/~simmons/images/lb7fig8.gif http://severinghaus.org/gallery/d/3752-1/DSCF6599_wheel_bug_spiracles_sm.jpg

34. Invertebrate Cardiovascular • Scorpions and spiders have book lungs • Similar to gills with gas exchange http://www.eurekalert.org/multimedia/pub/web/11627_web.jpg http://www.biologyreference.com/images/biol_02_img0189.jpg

35. Gills • Order of magnitude less oxygen in water than air (21% in air) • Aquatic organisms need to extract dissolved O2 • Counter current system http://www.trincoll.edu/~alehman/_images/Bio210_Spring05/ali_murineliver2200x_wd11_ap4_A.jpg http://wps.prenhall.com/wps/media/objects/1115/1141942/fig31-1.jpg

36. Fish Heart • Fish have a two chamber heart • Blood flows into atrium • Blood pumped out of ventricle • Travels to lungs and then to body http://www.cartage.org.lb/en/themes/Sciences/LifeScience/GeneralBiology/Physiology/CirculatorySystem/CirculatorySystem/VertebrateVascular/VertebrateVascular.htm

37. Amphibian Cardiovascular • Amphibians have a three chambered heart • Into right atrium to ventricle • Ventricle to lungs • Lungs to left atrium • Left atrium to ventricle • Ventricle to body

38. Reptiles • Lizards, snakes and turtles have 3-chambered hearts • Crocodiles have a 4-chambered heart • Evidence dinosaurs had 4-chambered hearts

39. Questions?