Osmosis

Osmosis
Osmosis: the movement of water molecules from an area of high concentration to an area of low concentration.

Cell membranes are completely permeable to water, therefore, the environment the cell is exposed to can have a dramatic effect on the cell.

Hypertonic Solutions: contain a high concentration of solute relative to another solution (e.g. the cell’s cytoplasm). When a cell is placed in a hypertonic solution, the water diffuses out of the cell, causing the cell to shrivel.

Hypotonic Solutions: contain a low concentration of solute relative to another solution (e.g. the cell’s cytoplasm). When a cell is placed in a hypotonic solution, the water diffuses into the cell, causing the cell to swell and possibly explode.

Isotonic Solutions: contain the same concentration of solute as an another solution (e.g. the cell’s cytoplasm). When a cell is placed in an isotonic solution, the water diffuses into and out of the cell at the same rate. The fluid that surrounds the body cells is isotonic.

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Bacteria Virus Worksheet Bl

 

Bacteria Worksheet   

 

 

 

Bacterial Cell Evolution

1. Bacteria are microscopic _____________.

2. Fossils evidence shows bacteria are about __________ years old, while eukaryotes are about __________ years old.

3. Discuss where bacteria can be found.

 

4. Ribosomal differences have put bacteria into what two kingdoms? Which is the older group?

 

5. What is absent in the cell wall of Archaebacteria? Describe this substance.

 

 

6. Describe the environments in which you would find Archaebacteria.

 

 

7. Compare & contrast these tree groups of Archaebacteria — methanogens, extreme halophiles, and thermoacidophiles.

 

 

 

 

8. Most bacteria are found in what kingdom?

9. Name & describe the three shapes of Eubacteria.

 

 

10. Are Eubacteria aerobic or anaerobic? Explain.

 

11. Eubacteria may be heterotrophic or photosynthetic. Explain what this means & give an example of each type.

 

 

12. What type of staining is used to group Eubacteria?

13. Describe the appearance of gram-positive and gram-negative bacteria under a microscope.

 

14. Explain why Eubacteria do not all stain the same color during Gram staining.

 

15. Describe, in detail, cyanobacteria.

 

 

16. Cyanobacteria, also known as ______________ bacteria lack a membrane bound __________ & _____________.

17. How are heterocysts helpful to cyanobacteria?

 

18. What is eutrophication?

 

19. Explain the role of cyanobacteria in eutrophication.

 

 

20. What bacterium causes syphilis? Describe this bacteria.

 

21. Streptococci bacteria causing strep throat are in what group?

22. Why are actinomycete bacteria important?

 

23. Compare & contrast these three groups of Proteobacteria — enteric bacteria, chemoautotrophs, and nitrogen-fixing bacteria.

 

 

 

 

24.Name a genus of nitrogen-fixing bacteria found on the roots of soybeans in our area.

 

Characteristics of Bacteria

25. Name the three main parts of all bacteria.

 

26. Describe the cell wall of bacteria. How does this differ from a plant cell wall?

 

 

27. Compare & contrast the cell membrane of Eubacteria with that of other eukaryotes.

 

 

28.Are Gram positive or negative bacteria more protected against antibiotics & why?

 

29. Where does cell respiration take place in eukaryotes? in bacteria?

30. Describe how the cell membrane of photosynthetic bacteria are adapted for this process. Where does this process take place in plants?

 

 

31. Compare & contrast the cytoplasm of bacteria with that of eukaryotes.

 

 

32. Describe the DNA (hereditary material) found in bacteria. Make a sketch of what you think this would look like.

 

 

 

33. Where is the capsule of a bacteria, what is it made of, and give two ways it helps a bacterium?

 

 

34. Where is the glycoclayx of a bacteria, what is it made of, and how does it help a bacterium?

 

35. How do pili help the bacteria that have them?

 

36. How do Gram positive bacteria protect themselves against harsh environments?

 

37. Describe two methods of locomotion in bacteria.

 

 

38. Compare & contrast saprophytic and photoautotrophic bacterial nutrition.

 

 

39. Distinguish among these three bacteria & give an example of each — obligate anaerobes, facultative anaerobes, & obligate aerobes.

 

 

 

 

40. Compare & contrast these three methods of bacterial reproduction — transformation, conjugation, and transduction.

 

 

 

Bacteria and Humans

41. What does a pathologist do for a living?

 

42. Compare & contrast the two types of toxins bacteria produce.

 

 

43. Besides injuring the body by releasing toxins, how else do bacteria hurt the body?

 

44. Describe four antibiotics against bacteria.

 

 

 

45. Explain how antibiotic resistance occurs.

 

 

46. Name two  bacterial diseases carried by ticks.

47. name two bacterial diseases caused by eating contaminated food.

48. Name a sexually transmitted bacterial disease.

49. Name a bacterium that can cause disease whenever it gets into deep wounds.

50. Name a bacterium that is transmitted by coughing & infects the lungs.

51. Describe, in detail, how bacteria can be useful to humans.

 


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PreAP Requirements

    Pre-AP Biology is an accelerated laboratory/lecture course for the highly motivated and academically talented science student. The skills and concepts the students will learn are ones that are necessary to be successful in Advanced Placement Biology.  Pre-AP Biology students should have above average ability in both science and mathematics and should  have strong reading comprehension skills. The course will require more out of class assignments and a more rigorous in class schedule of work.  Students will be ultimately responsible for their learning; therefore, they should be organized, prepared, and motivated to learn every day.

    Approximately 80 % of the student’s grade in AP Biology will come from tests & two major collections.  The remaining percentage of the grade will consist of homework and labs. There will be no extra credit work or bonus points given to raise the Pre-AP grade.

    The course of study will include the following topics — a brief review of chemistry, biochemistry, cellular biology, bioenergetics, heredity and  molecular genetics, evolution, structure & diversity of organisms, behavior, and ecology .  Scientific writing and problem solving are integrated into the course work.

If you are unorganized, unprepared, unmotivated, and not willing to work both in and outside of class, then Pre-AP Biology is not the course for you!!!

If you have good organizational skills, above average intelligence, are a good reader, and are highly motivated to learn, then welcome to an exciting and fun year in Pre-AP Biology!!!!

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