Welcome to Level 1 Science: Biology

1. Welcome to Level 1 Science:Biology Science 1.11 Biology 1.5

2. http://nhscience.lonestar.edu/biol/bio1int.htm#photo Vrisusresorucesat bottom

3. HIV • HIV Life Cycle http://www.sumanasinc.com/webcontent/animations/content/lifecyclehiv.html

4. Science 1.11 Bugs & Us “Interactions Between Humans & Micro-Organisms” AS 90950 Credits: 4 Internal Photo: Escherichia coli

5. Making Yoghurt Equipment • 250mL milk • 20g milk powder • 1T fresh yoghurt • Heating apparatus • Incubator Instructions 1. Place 250mL of milk into a large, clean beaker or jar 2. Heat milk until hot (do not allow it to burn) 3. Remove from heat. Add 20g milk powder. Mix. Chill until milk is lukewarm (about body temperature) 4. Add 1T yoghurt to milk. Mix gently. 5. Incubate at 30ºC for 24 hours.

8. Yogurt Bacteria Lactobacillus Bulgaricus Lactobacillus acidophilus Arrangement paired = diplo chained = strepto clusters = staphylo Shape round = coccus rod = bacillus spiral = spirillus + Bifidobacterium (a group with many species) Streptococcus thermophilus

9. Yr11, T1, 2012 (yogurt bacteria)

10. Yr11, T2, 2012 (yoghurt bacteria)(digital microscope)

11. Bacteria – In General • Size • # of species • Unicellular • Prokaryotes • Most are consumers • Parasites • Pathogens • Saprotrophs

12. Generalised Bacterial Structure

13. Bacteria: Functions of the Parts • Capsule • Cell wall • Cell membrane • Cytoplasm • Chromosome • Flagella

15. Bacterial MRS GREN (copy the below and add to it using pg 4 – you should include a diagram of binary fission (reproduction) and extra cellular digestion (nutrition). • Move – using flagella (protein based “motor”) • Respire – chemical reaction (react food with oxygen to produce energy add to this ) • Sensitivity – can detect chemicals in environment • Growth – cell can grow larger • Reproduction – by binary fission, when get to a certain size • Excretion – wastes (give an example) diffuse across cell membrane • Nutrition – feed by extra cellular digestion

16. Bacteria: Binary Fission

17. Bacteria: Extracellular Digestion

18. Bacterial Respiration

19. Fungi Clip • Reproduction, digestion – clickview Ch4

20. Fungi Questions (pg5) • Define the following: • Saprophyte • Hyphae • Spores • sporangia 2) How do fungi feed? 3) How do fungi reproduce? Sketch this. 4) How do fungi respire? 5) How do fungi excrete waste?

21. Viral MRS GREN Make your own notes using the following as prompts. M – Do they move on their own? How do they use hosts to move? R – Do they need to respire? Why not? S – Are they sensitive? How so? G – Do they grow / stay same size? R – Do they reproduce on their own? How do they replicate? Include labelled diagrams. E – do they excrete wastes? N – Do they require nutrition? Why not? Link to other processes

22. 1. Open up your PowerPoint presentation. Select the page into which you want to insert the animation into2. Go to View - Toolbars - Control Toolbox (figure 1) and click on the icon which looks like a little hammer3. Select "Shockwave Flash Object" (figure 2) from the list4. Drag a square onto the place where you want the Mix-FX file to appear5. After you have done this, right-click on the box, choose properties, and the properties menu will pop up6. To add the Mix-FX file you must click on "Custom", and select the "Build" icon (the three dots at the end of the line)7. Now enter the Movie URL (make sure that you enter the correct path!) and tick the "Embed Movie" box as well 8. Finally, save and run your slide show in presentation view

23. Viral Replication

24. 1. Yeast • Questions (Use “Living World” Pg4) • What did Leeuwenhoek find out and when? • What did Pasteur find out and when? • What is fermentation? • Describe how yeast is commercially grown

25. 8. Life History of an Epidemic • Epidemic: the spread of a disease on a large scale • Endemic: a disease present persistently at low levels in a population • Pandemic: the spread of a disease on a global scale • Vaccination: injection of modified micro-organisms to give resistance to a disease • Antibody: proteins produced by the immune system against a disease organism or its toxins

26. Yeast Suspension Recipe 1) In a boiling tube, in this order: Add 0.5g dried yeast 1 teaspoon sugar 30mL warm water Mix (if needed) 2) Name. Place in a test tube rack on window sill. Saccharomyces cerevisiae

27. Yeast Microscopy • Stain: Congo Red Live yeast in congo red

28. Yeast Microscopy Look for: living cells (clear) dead cells (blue) cells budding

29. Culturing / Binary Fission (recap) • http://www.youtube.com/watch?v=5Xi2Nc1UicQ

31. Subculturing • What? • Taking an agar plate with mixed species on it and producing a plate with pure colonies of only one species • Why? • A useful first step in bacterial identification • The size, shape, colour (etc) of the colonies may be useful in deciding which species is on the agar plate.

32. Pathogen Identification

33. Koch’s Postulates

34. Gram Stains(a useful first step in identifying a bacterial species) • Some bacteria: thick peptidoglycan cell wall • They retain stain (purple)when given gram stain procedure = gram positive • Some bacteria: thin peptidoglycan cell wall • They lose stain (look pink)when given gram stain procedure = gram negative

36. How does gram staining work? • Gram-positive bacteria have a thick mesh-like cell wall made of peptidoglycan (50-90% of cell envelope), which are stained purple by crystal violet, whereas Gram-negative bacteria have a thinner layer (10% of cell envelope), which are stained pink by the counter-stain. There are four basic steps of the Gram stain: • applying a primary stain (crystal violet(purple) to a heat-fixed smear of a bacterial culture. Heat fixing kills some bacteria but is mostly used to affix the bacteria to the slide so that they don't rinse out during the staining procedure. • the addition of a mordant, which binds to crystal violet and traps it in the cell (Gram's iodine) • rapid decolorization with alcohol or acetone, and • counterstaining with safranin; carbolfuchsin(pink) is sometimes substituted for safranin since it will more intensely stain anaerobic bacteria but it is much less commonly employed as a counterstain. http://en.wikipedia.org/wiki/Gram_staining#Staining_mechanism

37. Importance • The Gram stain is almost always the first step in the identification of a bacterial organism, and is the default stain performed by laboratories over a sample when no specific culture is referred. • While Gram staining is a valuable diagnostic tool in both clinical and research settings, not all bacteria can be definitively classified by this technique, thus forming Gram-variable and Gram-indeterminate groups as well.

40. Second line of defence • White Blood Cells (aka leukocytes) try to stop any pathogens that have entered the body. • Leukocytes are made in the bone marrow of long bones (eg femur) Types: • Phagocytes (attack & engulf pathogens) • Granulocyte – fast moving, attack foreign matter • Macrophage – swallow dead / foreign matter • Lymphocytes (produce chemicals) • B-lymphocyte cells – produce antibody (a Y shaped protein which recognises antigens (proteins) on a pathogen and inactivates or kills them. • T-lymphocyte cells – mature in the thymus gland, can kill infected body cells.

41. Vaccination • Questions, after reading page 24-25 • Describe what happens the first time you are infected with a pathogen • What is different the second time you are infected with the same pathogen? • How is the immune system able to work much more effectively the second time? • How were you protected from disease as a baby and before you were born? • What is meant by passive immunity? • Why is passive immunity not permanent? • What is vaccination? • What is active artificial immunity? • Explain the limits on the success of vaccination.

43. How do Antibiotics work?

45. Good & Bad Bugs nb: pathogen = a bacterium, virus, or other microorganism that can cause disease

46. Pathogens… • pathogen • Greek: πάθοςpathos, "suffering, passion" • γενήςgenēs (-gen) "producer of") • infectious agent — in colloquial terms, a germ — is a microorganism such as a virus, bacterium, prion, or fungus, that causes disease in its animal or plant host • pathology....

47. Helicobacter pylori H. Pylori, a bad guy. Uses multiple flagella to swim through mucus lining the stomach wall, it causes stomach ulcers.

48. Campylobacter jejuni SEM of C. jejuni, a bad guy. Causes food poisoning or campylobacteriosis (a notifiable disease) symptoms: abdominal pain, diarrhoea, fever, and malaise. Incorrectly prepared meat and poultry normally the source of infection.

49. Source: ODT

50. The rainbow bracket fungus (Trametesversicolor) is common on dead wood in forests and urban gardens. It grows to about 5–10 centimetres in diameter and has a velvety appearance, with distinct brown and white zones on its upper surface. Its lower surface contains thousands of pores, the ends of tubes in which spores are produced and released into the air.