Honors Biology

1. Honors Biology Module 2 Kingdom Monera September 5, 2013

2. Class Challenge

3. Homework Any Questions? • Finish OYO for Module 1 • Complete Study Guide for Module 1 • Complete labs in Lab book • Quiz: Biological Classification; diagram of Prokaryotic and eukaryotic cells • Read Module 2 pages 37-49. • Class challenge: Photoshop your head onto an animal. • Take test for Module 1

4. Quiz

5. Question 1 Name the classification groups in our hierarchical classification scheme in order. (King Philip cried out, “For goodness sake!”

6. Label the Prokaryotic Cell

7. Label the Eukaryotic Cell

8. Biological Classification Kingdom  Phylum  Class  Order  Family  Genus  Species

11. Kingdom Monera Kingdom Monera from a cellular point of view is probably the most diverse kingdom in creation. They are all composed of prokaryotic cells. • Scientists do not know all there is to know about these organisms. • Some of these organisms can survive in habitats that are deadly to other organisms. Examples from reading.

12. Bacteria Kingdom Monera organisms are essentially Bacteria. Not all bacteria is what you first think about that is associated with disease. There are many forms of bacteria that are beneficial to people. There are many forms of bacteria which are not only non-pathogenic, but are quite beneficial. Can you give us an example?

13. Bacteria that is in your gut that synthesize B Vitamins and Vitamin K. • Bacteria that makes cheese. • Cynobacteria uses photosynthesis to make their own food, also gives us oxygen to breathe. • Decomposing bacteria that perform the necessary job of recycling from dead organisms so that living organisms can use them.

14. Pathogen A pathogen is an organism that causes disease. Scientists call this a pathogenic bacterium. Bacteria belong to kingdom Monera, they are prokaryotic.

15. A prokaryotic cell Have no distinct membrane-bounded organelles. The “typical” bacterium has some general characteristics. • Capsule • Cell Wall • Plasma Membrane • Cytoplasm • DNA • Ribosomes • Fimbriae • Flagellum

16. What is Bacteria? http://youtu.be/pcXdfofLoj0

17. Micrometer 1 meter = about 3 feet A micrometer is one millionth of that size About 1000 bacteria would fit in the dot of This “ i ” .

18. Bacteria have capsules that protect the cell and, along with the help of fimbriae, allow it to attach to surfaces. • Bacteria have a cell wall that keeps the shape of he bacterium. • Inside the cell wall there is a plasma membrane that regulates the passage of substances in and out of the cytoplasm.

19. Bacterium have DNA which stores all of the information needed for the cell to be alive, and they have the ability to copy this DNA in a mere 20 minutes. • Bacterium have ribosomes which can produce complicated chemicals called proteins. • Bacterium have an advanced system of locomotion which strongly resembles the design of an outboard motor. • All contained in a cell barely 2 micrometers long.

20. Bacteria Represent the “simplest” form of life on earth! (See page 41 paragraph 1)

21. Eating habits of Bacteria All life must have a means of converting energy from its surroundings into energy that will sustain the processes necessary for life. • Some organisms do this by producing their own food– Producers. • Some eat other organisms – Consumers. • Some do it by decomposing dead organisms – Decomposers.

22. Saprophytes Most bacteria are decomposers. Since decomposers rely on other (dead) organisms for food, we can also say that they are heterotrophs. These bacteria are referred to as saprophytes. They are organisms that feed on dead matter.

23. Saprophytic Bacteria Are an integral part of nearly every aspect of nature. Without these microscopic decomposers, many of the materials on earth that are necessary for live would be contained in the bodies of only a few generations of dead organisms.

24. Since bacteria decompose dead organisms, these materials are recycled back into creation so living organisms can use them. Not all heterotrophic bacteria are saprophytic. Some bacteria (the ones that cause disease) are parasites.

25. Parasites Are organisms that feed on a living host. • Many bacteria lack the ability to digest nutrients, so they need to absorb nutrients that have already been digested. • They often lack the ability to manufacture the complex chemicals necessary for life so they absorb chemicals from their host.

26. Autotrophic Bacteria Even through most bacteria are heterotrophic, there are many forms of autotrophic bacteria. The two different means by which autotrophic Bacteria manufacture their own food: • Photosynthesis • Chemosynthesis

27. Photosynthesis Uses energy from the sunlight along with certain chemicals to make food for the autotrophic organism. In green plants and most of the other photosynthetic organisms, the byproduct of photosynthesis is oxygen.

28. Photosynthesis occurs in some bacteria, but oxygen is not the byproduct. This is because the chemicals that those bacteria use in photosynthesis are quite different from the chemicals used in the photosynthesis that is carried out by plants. The byproducts of photosynthesis from these bacteria are useful to certain organisms.

29. Chemosynthetic Bacteria Use a different process to manufacture their food. The main difference between photosynthesis and chemosynthetic is the source of energy. Instead of sunlight, bacteria promote chemical reactions which release energy. The bacteria then use that energy along with other chemicals to manufacture their food. Usually the chemical reactions convert chemicals that living organisms cannot use into chemicals that certain living organisms can use.

30. Digestion Once a bacterium has food, it converts it into energy to support life. In our bodies we break down food into small particles that our bodies can absorb. Digestion does not give us energy. In order to get energy, we must combine these molecules with oxygen in a long complicated chemical process. When we breathe so that wee get the oxygen we need to perform this complicated chemical process.

31. Aerobic/ Anaerobic Since we use oxygen in order to get energy from our food, humans are called Aerobic Organisms. There are certain types of bacteria that do not require oxygen in order to convert their food into energy. These bacteria are called AnaerobicOrganisms.

32. Anaerobic Bacteria Live in areas that are barren of oxygen such as deep underground or in the muck at the bottom of a swamp. These bacteria are essential to life, because they either decompose dead organisms or convert useless chemicals into chemicals that can be used by other life forms.

33. Bacteria have many different ways of getting their food, but they all in some way promote life on earth. Saprophytic bacteria recycle chemicals from dead organisms to live ones. Photosynthetic (autotrophic) bacteria produce certain useful chemicals that no other process on earth can produce.

34. Chemosynthetic (autotrophic) bacteria are adept at converting chemicals that are useless to living organisms into substances which are essential for life. Pathogenic bacteria have a role as well. A group of organisms gets too large and could destroy the balance of nature. A pathogenic bacteria will kill off a large number of the organisms, making sure that the balance of nature remains intact.

35. The Biosphere 2 See page 43.

36. Asexual Reproduction in Bacteria For an organism to be considered alive, it must be able to reproduce so that life can continue. There are several ways in which asexual reproduction can occur, we will concentrate on binary fission.

37. Asexual Reproduction Figure 2.4 (Page 45)

38. DNA Since DNA holds all of the information that makes up an organism, the two bacteria are identical. If a mistake is made while the DNA was being copied, there will be a marked difference between offspring and parent. This is called a mutation.

39. How long does it take for a cell to divide? Under ideal conditions, a bacterium can divide in about 20 minutes. Once it divides, then the new cell and the old one can divide again in about 20 minutes. If this process continued indefinitely, one bacterium and the old one could multiply into more than a billion bacteria in about 10 hours.

40. Bacterial growth under the microscope, Rate My Science http://youtu.be/4grQSLmWXQk

41. Steady State Suppose a saprophytic bacterium found its way to a dead cow. The bacterium would feed on the cow and begin to reproduce rapidly. In just a day or two there would be billions of bacteria spread across the dead cow having access to all of the nutrients that they need. Once bacteria covers all of the dead cow, what happens next?

42. Steady State Some bacteria would be cut off from the food supply and would begin to die decreasing the population of bacteria. However, bacteria would still be reproducing while others would be dying off. At some point the bacteria’s population would reach a point where the number of new bacteria formed would equal the number that are dying off. Scientists call this the steady state of a population.

43. Figure 2.5 page 46 The bacteria would reach a steady state for a while, then what happens? The cow’s remains start to dwindle due to all of the bacteria feeding on it and now would not support the bacteria’s population. Then bacteria will start eating other bacteria. Eventually when all of the cow’s remains are gone, all of the bacteria would be dead.

44. Limitation of Resources Even when bacteria can populate an area quickly, a limitation of resources will eventually slow the growth of the population until, when all the resources run out, the population dies.

45. Exponential Growth Going back to Figure 2.5, look at the initial stage of population growth. The bacterial are reproducing unchecked. There are plenty of resources for the population, so now the population grows as quickly as the bacteria can reproduce itself.

46. Logistic Growth As the population begins to reach the limits of the environment’s resources, it can no longer grow unchecked. The population growth is controlled by the limited resources of the environment.

47. Sigmoidal Curve Look at the highlighted pink region. (Logistic Growth) When you graph a population that experiences logistic growth, you get the S-Shaped curve called the Sigmoidal Curve.

48. Genetic Recombination in Bacteria When bacteria reproduce asexually, the offspring is a genetic copy of the parent. However it is often beneficial for bacteria to exchange genetic information in order to increase the genetic diversity of the population. This can be achieved in three ways:

49. Genetic Recombination • Conjugation: A temporary union of two organisms for the purpose of DNA transfer. • Transformation: The transfer of a DNA segment from a nonfunctional donor cell to that of a function recipient cell. • Transduction: The process in which infection by a virus results in DNA being transferred from one bacterium to another

50. Examples of live bacteria in the saliva http://youtu.be/hC0jeNUyQ9s