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Bio 11 SS Bacteria Vocab

Bacteria Vocab List

 

1. Aerobic  
2. Anaerobic  
3. Anaerobic respiration  
4. antibiotic  
5. Antitoxin  
6. Autotrophic  
7. Bacillus  
8. Binary Fission  
9. Blue green algae  
10. Cell wall  
11. Chemosynthetic  
12. Chemotaxia  
13. Chemotherapy  
14. Cocci  
15. Conjugation  
16. Endospore  
17. Fermentation  
18. Flagella  
19. Heterotrophic  
20. Pathogen  
21. Penicillin  
22. Photo taxis  
23. Photosynthetic  
24. Pplo  
25. Respiration  
26. Rickettsia  
27. Spirochetes  
28. Staphylococci  
29. Streptococci  
30. Streptomycin  
31. Toxin  
32. Vaccine  
posted by Marc Bernard Carmichael in Biology Eleven,Biology Eleven Notes,Micro Bio,Microbio and have No Comments

History of world and pathology assignment

Biology 11 : History of Pathology Time line

There is something known as the “butterfly affect”, https://en.wikipedia.org/wiki/Butterfly_effect

The premise is that one small change can have a large affect. In Biology, a simple observation can sometimes lead to a discovery that save millions of lives. How could how one event affects another? How is it that rapid changes in on pursuit of knowledge can be linked to world history.

Using the following table you are to compare World History to the history of medicine and pathology.

  • In History of Pathology and Medicine you should included :
  • You should seek out the history, pathology and epidemics linked to HIV virus and Spanish Flu, E. Coli and Staphylcoccus, and Malaria and Trypanosoma.
  • You should also include new discoveries for curing disease, and the names of those who brought forth the discovery. ( examples: Morgani, Jenner, Pasteur, Walter Reed, Dr. Don Francis, Dr. Robert Gallo, Francoise Barre-Snoussi)

In world events, you should keep track of:

  • majour wars on the planet, changes in transportation and trades, periods of renaissance, revolutions (social and industrial), changes in human transportation and changes in world economy ( examples: world disasters such as Potato famine, Panama Canal, World Wars 1 and 2, and the Industrial revolution.

You are to use: Online resources (please cite your bibliography), including “Wikipedia” and

World History Date History of Pathology and Medicine
1700

 

Comparative Questions

  1. How is the changes of movement of people linked to how diseases moved?
  2. Was the Spanish flu really from Spain?
  3. What 10 year period of time showed the greatest change both in world history and pathology?
  4. Hypothesize why this may have occurred.
  5. What three world events had the greatest affect upon pathology and medicine?
  6. What five events in the history of pathology may have had the greatest affect upon humanity?
  7. What new historical facts have changed previous ideas about any of the mentioned diseases?
  8. What world events may have limited research into a particular disease?
  9. What world events may have accelerated epidemics of a disease?
  10. What world events may have accelerate research into a disease?
posted by Marc Bernard Carmichael in Biology Eleven,Biology Eleven Notes,Micro Bio,Microbio,Protist and have No Comments

Inquiry into Bacteria Notes

Inquiry into Bacteria:

 

These are focus question to help design your Data Sheet

 

Topic One: Myths and Monera

 

Prior to making your data sheet consider what comes to your mind when you hear or read the term bacteria?

 

Some questions you may want to consider while reading the text:

  • Where are bacteria found?
  • Are most bacteria harmful?
  • How are bacteria related to other organisms?
  • What is the difference between a prokaryote and eukaryote
  • How are the activities of life useful in examining how bacteria interact with other species?

 

Topic Two: The problems of classification

 

Here is the first thing to consider:

  • What was the original system to classify organisms?
  • What properties or observations did this system use for classification?
  • Can these observations be used to classify microscopic organism?
  • What techniques could be used to establish observational criteria?
  • What are some limitations of classifying organism based upon structures?

 

 

 

 

Topic Three: Metabolic Perspectives

 

Now we have gone molecular, so how can metabolic pathways provide a new way to classify organism?

Consider the following

  • How do organism get or make their energy?
  • How do organisms feed themselves?
  • How is the environment related to metabolism?

 

Topic Four Interactions with Humans

Positive Interactions

  • What are the top ten positive interactions with bacteria?

 

Negative Interactions

  • How is metabolism and structure related to negative interactions?
  • How are negative interactions prevented?

(from a macrobiotic to molecular perspectives)

 

Topic Five: Playing with critters!

  • What is the criteria for sanitary technique?
  • How can metabolic activities be used make observations about bacteria?
  • What simple tests and ideas can we create?

 

Topic Six: Creating a testable experiment!

  • You will be responsible for creating an experiment!

 

 

Bacteria Notes:

Part One: Unity and Diversity

Ways to classify bacteria

  • Shape and size
  • Gram positive and Gram negative
  • Metabolism (include respiration and food source)
  • Archeo and Eubacteria

 

  1. Size and Shape
  • Bacteria were first described by Leeuwenhoek in 1677 after he had invented the compound microscope.
  • Bacteria range in size from about 1 to 10 um long by about 0.2 to 0.3 um across (1 um = .001 mm).

 

Most true bacteria come in one of three different shapes:

(1) Rod shaped: Bacillus(i) [filaments or single].

(2) Spherical shaped: Coccus(i) [pairs, chains, groups or single].

(3) Spiral shaped: Spirillum(a) [seldom in colonies]

Some bacteria tend to form groups:

Diplococci are pairs of spherical shaped bacteria

Streptococci are chains of spherical shaped bacteria

Staphylococci are clusters of spherical shaped bacteria

 

B: Gram positive and Gram negative

 

The term gram positive or negative, refers to both a staining proccess and specific structure of bacterial cell membranes or wall. The gram staining method is one of the more important techniques in microbiology. Yet one has to realize that this technique is not 100 percent fool proof. Differences in results can be due to type of stains and age of bacteria.

  • The staining process follows the following protocal:
  • Heat fix bacteria to slide
  • Stain with purple dye (crystal violet), rinse with distilled water
  • Stain with with iodine (marker), rinse with water
  • Rinse with alchol wash, functions as a decolorization process in which negative lose colour.
  • Stain with safranin (red stain) which is counter stain for gram negative

 

In regards to cell membrane structures:

 

Gram positive bacteria have cell walls composed of peptidoglycan (murein) and teichoic acid. ( basically a sugar based structure combined with amino acids)

 

Gram negative bacteria also have cell walls composed of a peptidoglycan ( in small amounts) but this layer is surrounded by a lipopolysaccharide outer membrane.

 

Comparison of Characteristic of Gram + and Gram –

Characteristic Gram Positive Gram Negative
Gram Reaction Stain dark violet or purple Stain pink
Ratio RNA to DNA 8:1 1:1
Nutritional requirements More complex Less complex
Susceptability to penicillin Marked Less marked
Susceptability to streptomycin and tetracycline Much less Marked
Susceptability to anionic detergents Marked Less marked
Resistance to sodium azide Marked Less marked

 

C: Metabolism and Nutrition

Cell Metabolism:

Nutrients are ingested and then:

  1. broken down by enzymes within cell
  2. further breakdown of material is done to produce energy
  • Energy is absorbed by biochemical ADP (adenine di phosphate)
  • Energy is released by biochemical ATP ( adenine tri phosphate)

 

Energy can be produced with or without oxygen

  1. Anearobic: are bacteria that do not need oxygen for cell metabolism
  2. Areorobic: are bacteria that require oxygen for cell metabolism
  3. Facualtative: are bacteria that can metabolize with or without oxygen
  • Obligate Aerobes are those which must have oxygen
  • Obligate Anaerobes are bacteria which cannot tolerate

 

There are many types of nutrition found among bacteria:

 

Autotrophic Nutrition:

  1. Some are photosynthetic (use sunlight energy to produce their own food).
  2. Some are chemosynthetic (oxidize inorganic compounds to obtain their

energy to produce their own food).

  • These organisms are known as Photoautotrophs and Chemoautotrophs in that they manufacture their own food.

Heterotrophic Nutition.

They must obtain their energy and nutrients from other sources.

For example:

  • Saprophytic bacteria : digest materials in their environment by releasing powerful digestive enzymes. They then absorb the digested nutrients.
  • Parasitic bacteria : rely on other organisms to provide the digested nutrients directly.

 

 

Part Two: Interactions

Bacteria can exist everywhere there is life this includes:

  • in the air
  • in the water
  • in the earth
  • on plants
  • in organism
  • without bacteria, we as humans could not exist
  • bacteria are the most primitive form of life because they:
  1. a) grow and reproduce ( as often as one time every 15-25 minutes)
  2. b) they use nutrients to survive
  3. c) they have simple cell structures
  • it is possible to see bacteria through a light or electron microscope
  • Bacteria are both helpful and harmful
  • To preserve or stop bacteria metabolism they can be:

chilled

dried out

frozen

heated

 

Dangerous bacteria are called pathogens because they cause diseases.

  • to control pathogenic bacteria you can remove bacteria by:

removing all bacteria using extreme heat

wash with antiseptic soaps

use antibiotics

specific immunization for specific bacteria proteins

  • Some bacteria can become resistant to antibodies by altering protein coat or structure of cell wall.
  • Bacteria can change into dormant forms called spores, which allow the bacteria to stop metabolism in extremely harsh environments

 

Useful Bacteria (at least 12 reasons!)

Most bacteria are not pathogenic — include decomposers, nitrogen

fixing bacteria, vitamin producing bacteria, bacteria used to make

insulin and growth hormone, bacteria used in dry cleaning, tanning,

cheese, yogurt

 

Essential Bacteria:

Bacteria can be helpful because:

  • they help plants absorb nutrients from the soil ( specifically nitrogen)
  • they are used to make milk products such as yogurt, cheese and butter
  • they can be used to manufacture antibiotics
  • they can alter biproducts from sewage treatments into non toxic waste
  • they can be used to produce specific gases such as methane
  • they are used for fermentation

 

  • Escherichia coli Gram – rod shape (bacilli)
  • Sarcina lutea Gram + round shape (cocci)
  • Bacillus subtilis Gram + rod shape (bacilli)
  • Bacillus cereus Gram + rod shape (bacilli)
  • Serratia marcescens Gram – rod shape (bacilli)
  • Rhodospirillum rubrum Gram – spiral shape (spirilla)

 

Harmful Bacteria

Harmful bacteria can cause disease (Pathogenic) by interfering with the host’s normal routine, by destroying cells and tissues, by producing endotoxins and exotoxins, and by eliciting an immune response.

  • An endotoxin is a toxin within the bacterium that is only released when the bacterium dies and it breaks down.
  • An exotoxin is a toxin released by living bacteria.

 

Koch’s Postulates: –

used to prove that an organism is responsible for a particular disease.

  1. must be shown that the organism in question is always present in

the diseased hosts.

  1. microbe must be isolated from the host and grown in a pure

culture.

  1. microbe from pure culture must be capable of producing the

disease symptoms in a new healthy host.

  1. microbes isolated from the newly infected host must be grown in a

pure culture and compared to the original micro-organism.

 

Examples:

  1. a) Respiratory Tract: Strep throat, Rheumatic fever, Scarlet fever;

Pneumonia, Whooping cough, Diphtheria, Tuberculosis…

  1. b) Skin: Staph (pimples and boils), Leprosy, Gas gangrene…
  2. c) Nervous System: Tetanus, Botulism, Meningitis…
  3. d) Digestive System: Typhoid fever, Cholera, Dysentery; (food

poisoning) Salmonella, Botulism, Staph…

  1. e) Venereal Diseases: Gonorrhea, Syphilis…

 

 

 

Infection by bacteria

There are three lines of defence through which bacteria must

penetrate:

  1. a) through the strong epidermal tissue (skin).. .in wounds, pores,

openings.

  1. b) phagocytic white blood cells which engulf foreign materials including bacteria.
  2. c) antibodies produced by other white blood cells.

 

Active Immunity

– is slow acting (because the body is taking time to produce antibodies against the infection); but long lasting (because the body produces “memory cells” which “remember” how to produce these specific antibodies again).

Normally produced by actual initial infection (chicken pox), or by using a vaccine (polio, smallpox). The vaccine consists of either weakened (attenuated) bacteria, dead bacteria, or artificial products which resemble the actual foreign invader (antigen).

 

Passive Immunity

This is fast acting (because the person is injected with antiserum containing the necessary antibodies or antitoxin); but short-lived (because the person does not actually produce the antibodies – hence no memory cells for the future!). The protein antibodies are often provided from the blood of a larger animal such

as a horse! (Tetanus, Rabies). New techniques have been designed so that bacteria can produce specific antibodies. Newborns initially have Passive Immunity through the passage of antibodies across the placenta, and in the Mother’s milk. In some cases, injection of Toxoids stimulate the production of natural antitoxins.

 

Antibiotics a biological substance which will kill or slow (inhibit) the growth of an organism.

e.g. Penicillin, Tetracycline, Bacitracin, Ampicillin,

Erythromycin…

  1. a) must be bacteria-specific.
  2. b) some people are allergic to certain antibiotics.
  3. c) some could kill off useful bacteria.
  4. d) may reduce the competitive pressure and allow

harmful bacteria to survive.

  1. e) may cause resistant strains to develop.

Other biocides include: Sulfur Drugs, antitoxins, various

bacteriocides, disinfectants…

 

Part Three: Changes with time

Reproduction

 

  1. Bacteria reproduce mostly asexually by a process called BinaryFission. In this method, the circular ring of DNA replicates, and then the cell divides into two daughter cells — each with its own DNA.

 

  1. Some bacteria can also undergo sexual reproduction by a process called Conjugation. In this method, the “male” is connected to the “female” by a tube called a Pilus. The DNA from the “male” then travels through the tube to the “female”. Here, it recombines with the “female” DNA and the “female” bacterium then divides.

 

  • Some bacteria can be Transformed into a different cell by absorbing fragments of DNA of other cells. In another method of producing recombined bacterial DNA, bacteriophages (viruses) carry portions of the bacterial DNA from one cell to another. This process is called Transduction.

 

 

  1. When environmental conditions are not favourable, some bacteria are capable of forming highly resistant thick-walled Endospores until conditions once again return to normal.

 

Part Four Form and Function

Cell Structure:

A bacteria cell has the following structures:

  • Nuclear material in the form of DNA to pass on genetic information
  • Cell membrane: which controls the flow of material in and out of a cell
  • Ribosome: which assist in making cell proteins
  • Cell wall
  • Flagella
  • Endospores

 

Bacteria Lab Questions:

  1. Why must you always use sterile technique when working with bacteria?
  2. What does “pathogenic” mean?
  3. What is an “inoculum”?
  4. List three general rules for handling bacteria.
  5. When is the Pour Plate Method of culturing bacteria used?
  6. Why must you be careful in regulating the temperature of the melted agar in the Pour Plate Method?
  7. In procedure 7 in each of the labs, why did you have to flame the mouths of the test tubes?
  8. What is the reason for using the streak plate method?
  9. What is the reason for using the Pour plate method?

 

posted by Marc Bernard Carmichael in Biology Eleven,Biology Eleven Notes,Microbio and have No Comments

Microbiology PLO’s

BIOLOGY 11 UNIT E – MICROBIOLOGY

 

  1. PRESCRIBED LEARNING OUTCOMES

By the end of this unit, you must be able to:

 

  1. show an understanding of characteristics and functions of viruses and bacteria.

 

  1. Viruses
  • evaluate the evidence used to classify viruses as living or non-living
  • describe the structure of viruses
  • describe viral reproduction
  • evaluate the effects of viruses on humans
  1. Monera
  • analyse monerans as a lifeform at the prokaryotic level of organization
  • describe the structure and function of bacteria
  • describe moneran diversity
  • describe the roles and effects of bacteria
  • evaluate the effectiveness of various antibiotics, disinfectants, or antiseptics on bacterial cultures

 

 

  1. VOCABULARY

By the end of this unit, you must be able to define the following:

 

o     antibody

o     antigen

o     DNA

o     host cell

o     lymphocyte,

o     lysogenic cycle

o     lytic cycle

o     membranous envelope,

o     mucous membrane

o     nucleic acid core

o     phagocytic white blood cell

o     primary line of defence

o     protein capsid

o     RNA

o     secondary line of defence

o     tertiary line of defence

o     viral specificity

o     white blood cell

o     aerobic respiration

o     antibiotic

o     antiseptic

o     bacteria

o     binary fission

o     classification

o     conjugation

o     disinfectant

o     ecological role

o     fermentation

o     motility

o     mutate/mutation

o     photosynthesis

o     prokaryote

o     resistant/resistance

 

posted by Marc Bernard Carmichael in Biology Eleven,Biology Eleven Notes,Microbio and have No Comments

Eubacteria (true bacteria) Notes

True Bacteria Notes:

Part One: Unity and Diversity

 

Ways to classify bacteria

  • Shape and size
  • Gram positive and Gram negative
  • Metabolism (include respiration and food source)

A. Size and Shape

  • Bacteria were first described by Leeuwenhoek in 1677 after he had invented the compound microscope.

 

  • Bacteria range in size from about 1 to 10 um long by about 0.2 to 0.3 um across (1 um = .001 mm).

 

Most bacteria come in one of three different shapes:

 

(1) Rod shaped:                             Bacillus(i)     [filaments or single].

 

(2) Spherical shaped:                    Coccus(i)     [pairs, chains, groups or single].

 

(3) Spiral shaped:                         Spirillum(a)     [seldom in colonies]

 

Some bacteria tend to form groups:

 

Diplococci                                        are pairs of spherical shaped bacteria

 

Streptococci                                    are chains of spherical shaped bacteria

 

Staphylococci                                 are clusters of spherical shaped bacteria

B: Gram positive and Gram negative

The term gram positive or negative, refers to both a staining proccess and specific structure of bacterial cell membranes or wall. The gram staining method is one of the more important techniques in microbiology. Yet one has to realize that this technique is not 100 percent fool proof. Differences in results can be due to type of stains and age of bacteria.

 

  • The staining process follows the following protocal:
  1. Heat fix bacteria to slide
  2. Stain with purple dye (crystal violet), rinse with distilled water
  3. Stain with with iodine (marker), rinse with water
  4. Rinse with alchol wash, functions as a decolorization process in which negative lose colour.
  5. Stain with safranin (red stain) which is counter stain for gram negative

 

 

 

 

In regards to cell membrane structures:

  • Gram positive bacteria have cell walls composed of peptidoglycan (murein) and teichoic acid. ( basically a sugar based structure combined with amino acids)
  • Gram negative bacteria also have cell walls composed of a peptidoglycan ( in small amounts) but this layer is surrounded by a lipopolysaccharide outer membrane.

 

Comparison of Characteristic of Gram + and Gram –

Characteristic Gram Positive Gram Negative
Gram Reaction Stain dark violet or purple Stain pink
Ratio RNA to DNA 8:1 1:1
Nutritional requirements More complex Less complex
Susceptability to penicillin Marked Less marked
Susceptability to streptomycin and tetracycline Much less Marked
Susceptability to anionic detergents Marked Less marked
Resistance to sodium azide Marked Less marked

 

C: Metabolism and Nutrition

 

Cell Metabolism:

Nutrients are ingested and then:

  1. broken down by enzymes within cell
  2. further breakdown of material is done to produce energy
  • Energy is absorbed by biochemical ADP (adenine di phosphate)
  • Energy is released by biochemical ATP ( adenine tri phosphate)

 

Energy can be produced with or without oxygen

  1. Anearobic: are bacteria that do not need oxygen for cell metabolism

 

  1. Areorobic: are bacteria that require oxygen for cell metabolism

 

  1. Facualtative: are bacteria that can metabolize with or without oxygen

 

  • Obligate Aerobes are those which must have oxygen
  • Obligate Anaerobes are bacteria which cannot tolerate

 

There are many types of nutrition found among bacteria:

 

Autotrophic Nutrition:

 

  1. Some are photosynthetic (use sunlight energy to produce their own food)

.

  1. Some are chemosynthetic (oxidize inorganic compounds to obtain their

energy to produce their own food).

  • These organisms are known as Photoautotrophs and Chemoautotrophs in that they manufacture their own food.

 

Heterotrophic Nutrition.

They must obtain their energy and nutrients from other sources.

For example:

  • Saprophytic bacteria : digest materials in their environment by releasing   powerful digestive enzymes. They then absorb the digested nutrients.

 

  • Parasitic bacteria : rely on other organisms to provide the digested nutrients directly.

Part Two: Interactions

Bacteria can exist everywhere there is life this includes:

in the air

in the water

in the earth

on plants

in organism

  • without bacteria, we as humans could not exist
  • bacteria are the most primitive form of life because they:
  1. a) grow and reproduce ( as often as one time every 15 minutes)
  2. b) they use nutrients to survive
  3. c) they have simple cell structures
  • it is possible to see bacteria through a light or electron microscope
  • Bacteria are both helpful and harmful
  • To preserve or stop bacteria metabolism they can be:

chilled

dried out

frozen

heated

 

Dangerous bacteria are called pathogens because they cause diseases.

 

  • to control pathogenic bacteria you can remove bacteria by:

removing all bacteria using extreme heat

wash with antiseptic soaps

use antibiotics

specific immunization for specific bacteria proteins

 

  • Some bacteria can become resistant to antibodies by altering protein coat or structure of cell wall.

 

  • Bacteria can change into dormant forms called spores, which allow the bacteria to stop metabolism in extremely harsh environments

 

Useful Bacteria

Most bacteria are not pathogenic — include decomposers, nitrogen

fixing bacteria, vitamin producing bacteria, bacteria used to make

insulin and growth hormone, bacteria used in dry cleaning, tanning,

cheese, yogurt

 

Essential Bacteria:

Bacteria can be helpful because:

  • they help plants absorb nutrients from the soil ( specifically nitrogen)
  • they are used to make milk products such as yogurt, cheese and butter
  • they can be used to manufacture antibiotics
  • they can alter biproducts from sewage treatments into non toxic waste
  • they can be used to produce specific gases such as methane
  • they are used for fermentation

 

 

Escherichia coli                              Gram – rod shape   (bacilli)

Sarcina lutea                                    Gram + round shape (cocci)

Bacillus subtilis                               Gram + rod shape   (bacilli)

Bacillus cereus                                Gram + rod shape   (bacilli)

Serratia marcescens                      Gram – rod shape   (bacilli)

Rhodospirillum rubrum                 Gram – spiral shape (spirilla)

 

Harmful Bacteria

 

Harmful bacteria can cause disease (Pathogenic) by interfering with the host’s normal routine, by destroying cells and tissues, by producing endotoxins and exotoxins, and by eliciting an immune response.

  • An endotoxin is a toxin within the bacterium that is only released when the bacterium dies and it breaks down.
  • An exotoxin is a toxin released by living bacteria.

 

Koch’s Postulates: –

used to prove that an organism is responsible for a particular disease.

 

  1. must be shown that the organism in question is always present in

the diseased hosts.

 

  1. microbe must be isolated from the host and grown in a pure

culture.

 

  1. microbe from pure culture must be capable of producing the

disease symptoms in a new healthy host.

 

  1. microbes isolated from the newly infected host must be grown in a

pure culture and compared to the original micro-organism.

 

Examples:

 

  1. a) Respiratory Tract: Strep throat, Rheumatic fever, Scarlet fever;

Pneumonia, Whooping cough, Diphtheria,                                                                    Tuberculosis…

 

  1. b) Skin: Staph (pimples and boils), Leprosy, Gas gangrene…

 

  1. c) Nervous System: Tetanus, Botulism, Meningitis…

 

  1. d) Digestive System: Typhoid fever, Cholera, Dysentery; (food

poisoning) Salmonella, Botulism, Staph…

 

  1. e) Venereal Diseases: Gonorrhea, Syphilis…

 

Infection by bacteria

 

There are three lines of defence through which bacteria must

penetrate:

 

  1. a) through the strong epidermal tissue (skin).. .in wounds, pores,

openings.

  1. b) phagocytic white blood cells which engulf foreign materials including
  2. c) antibodies produced by other white blood cells.

 

Active Immunity

Is slow acting (because the body is taking time to produce antibodies against the infection); but long lasting (because the body produces “memory cells” which “remember” how to produce these specific antibodies again).

 

Normally produced by actual initial infection (chicken pox), or by using a vaccine (polio, smallpox). The vaccine consists of either weakened (attenuated) bacteria, dead bacteria, or artificial products which resemble the actual foreign invader ( biological antigen).

 

Passive Immunity

This is fast acting (because the person is injected with antiserum containing the necessary antibodies or antitoxin); but short-lived (because the person does not actually produce the antibodies – hence no memory cells for the future!). The protein antibodies are often provided from the blood of a larger animal such

as a horse! (Tetanus, Rabies). New techniques have been designed so that bacteria can produce specific antibodies. Newborns initially have Passive Immunity through the passage of antibodies across the placenta, and in the Mother’s milk. In some cases, injection of Toxoids stimulate the production of natural antitoxins.

 

Antibiotics a biological substance which will kill or slow (inhibit) the growth

of an organism.

e.g.                             Penicillin, Tetracycline, Bacitracin, Ampicillin,

Erythromycin…

 

  1. a) must be bacteria-specific.
  2. b) some people are allergic to certain antibiotics.
  3. c) some could kill off useful bacteria.
  4. d) may reduce the competitive pressure and allow

harmful bacteria to survive.

  1. e) may cause resistant strains to develop.

 

Other biocides include: Sulfur Drugs, antitoxins, various

bacteriocides, disinfectants…

 

Part Three: Changes with time

Reproduction

 

  1. Bacteria reproduce mostly asexually by a process called BinaryFission. In this method, the circular ring of DNA replicates, and then the cell divides into two daughter cells — each with its own DNA.

 

  1. Some bacteria can also undergo sexual reproduction by a process called Conjugation. In this method, the “male” is connected to the “female” by a tube called a Pilus. The DNA from the “male” then travels through the tube to the “female”. Here, it recombines with the “female” DNA and the “female” bacterium then divides.

 

  1. Some bacteria can be Transformed into a different cell by absorbing fragments of DNA of other cells. In another method of producing recombined bacterial DNA, bacteriophages (viruses) carry portions of the bacterial DNA from one cell to another. This process is called Transduction.

 

  1. When environmental conditions are not favourable, some bacteria are capable of forming highly resistant thick-walled Endospores until conditions once again return to normal.

Part Four Form and Function

Cell Structure: A bacteria cell has the following structures:

  • Nuclear material      in the form of DNA to pass on genetic information
  • Cell membrane:      which controls the flow of material in and out of a cell
  • Ribosome:                which assist in making cell proteins
  • Cell wall
  • Flagella
  • Endospores

 

Response to Stimulus:

 

Bacteria Lab Questions:

 

  1. Why must you always use sterile technique when working with

bacteria?

 

  1. What does “pathogenic” mean?

 

  1. What is an “inoculum”?

 

  1. List three general rules for handling bacteria.

 

  1. When is the Pour Plate Method of culturing bacteria used?

 

  1. Why must you be careful in regulating the temperature of the melted agar in the Pour Plate Method?

 

  1. In procedure 7 in each of the labs, why did you have to flame the mouths of the test tubes?

 

  1. What is the reason for using the streak plate method?

 

 

  1. What is the reason for using the Pour plate method?

 

 

Designing an experiment.

 

  • From these biological facts, could you design a lab to test a simple hypothesis?
  • After you have a simple hypothesis…design a simple lab that can be done in less than one week. It should include both quantitative and qualitative data.

 

 

 

 

 

 

posted by Marc Bernard Carmichael in Biology Eleven,Biology Eleven Notes,Microbio and have No Comments

Inquiry into Bacteria

Inquiry into Bacteria:

 

Topic One:    Myths and Monera

 

Prior to doing this assignment consider what comes to your mind when you hear or read the term bacteria?

 

Some questions you may want to consider while reading the text:

  • Where are bacteria found?
  • Are most bacteria harmful?
  • How are bacteria related to other organisms?
  • What is the difference between a prokaryote and eukaryote
  • How are the activities of life useful in examining how bacteria interact with other species?

 

Topic Two:    The problems of classification

 

Here is the first thing to consider:

  • What was the original system to classify organisms?
  • What properties or observations did this system use for classification?
  • Can these observations be used to classify microscopic organism?
  • What techniques could be used to establish observational criteria?
  • What are some limitations of classifying organism based upon structures?

 

 

Topic Three:             Metabolic Perspectives

Now we have gone molecular, so how can metabolic pathways provide a new way to classify organism?

 

           Consider the following

 

  • How do organism get or make their energy?
  • How do organisms feed themselves?
  • How is the environment related to metabolism?

 

 

Topic Four    Interactions with Humans

 

           Positive Interactions

 

  • What are the top ten positive interactions with bacteria?

 

 

           Negative Interactions

 

  • How is metabolism and structure related to negative interactions?
  • How are negative interactions prevented?

(from a macrobiotic to molecular perspectives)

 

 

Topic Five:    Playing with critters!

 

  • What is the criteria for sanitary technique?
  • How can metabolic activities be used make observations about bacteria?
  • What simple tests and ideas can we create?

Topic Six:      Creating a testable experiment!

  • You will be responsible for creating an experiment!

 

Refernces for all these questions can be found in:

Bacteria Notes

 

 

 

posted by Marc Bernard Carmichael in Biology Eleven,Biology Eleven Notes,Microbio and have No Comments

Biology 11 Top Ten Virus Question

Mr. C’s Top Ten Questions About Virus

 

Question One: Are Virus living things?

 

 

Non living Characteristics Living Characteristics
they do not respire they do have DNA or RNA
there is no cellular structure they do have proteins and enzymes
they do not grow they have the potential to make other cells make copies of themselves, this is more like duplication than reproduction
they can be crystallised due to harsh environments virus show diversity associated with the hosts they infect
they cannot reproduce on their own * this is a great table for a test question….

 

Question Two: What are virus and where did they come from?

 

  • Virus may be linked to the original entity of life as a noncellular ancestor of cells
  • Their means of existence may imply that they were once primitive organisms that loss cell structures in order to assist parasitic lifestyle.
  • The genetic material within a virus is only a fragment of an original genome.

 

Question Three:

What is the structure of a virus and how is it associated with its lifestyle.

  • Most virus are composed of a protein coat which surrounds a small fragment of DNA or RNA.
  • Most virus are only visible with electron microscopes ranging in size from .015 to .45 microns.
  • Some of the protein coats are specialised for the host that the virus infects.
  • The shape of the protein coat may vary from spherical shapes to bacteriophage which have additional structures to add attachment to host.
  • Shapes are usually spherical, rod shaped or tadpole shaped.

 

Question Four: How are virus classified?

  • Virus are classified by the host they infect
  • Plant virus: ( example tobacco mosaic virus)
  • Animal ( by class: Aves : Bird, Insecta: insects) virus
  • Bacteria virus or Bacterio phage

 

Question Five: How are virus transmitted?

  • In plants: virus can be transmitted from contact with insects, direct contact between plant seeds, leaves or stems.

 

  • In animals: virus can be transmitted from coughing, sneezing, talking, direct contact and insects.

 

Question Six: How do virus infect host

A general infection follows the following pattern.

  1. The virus comes in contact with host cell and attaches to host cell.
  2. Viral Protein coat is either removed after absorption by host or virus injects nucleic material into host.
  3. Viral DNA or RNA is replicated by the host cell.
  4. Replicated viral DNA or RNA is translated into proteins for viral enzymes and protein coat.
  5. New virus are assembled within host cell from replicated and translated material.
  6. Virus either remain in host or host cell breaks due to too many virus within cell.

 

Specialised infections:

Bacteriophage: Virus that infect bacteria

In this type of infection there is the possibility of two events

  1. a) A lytic cycle
  1. Virus attaches to host bacteria, an enzyme eats away the host’s cell wall and   viral nucleic material is injected into host
  2. Viral nucleic material is incorporated into host nucleic material
  3. Viral nucleic material begins to replicate and translate its code, this takes over the bacteria normal cellular functions.
  4. As many as 100 or more copies of the original virus are made by host bacteria
  5. The host bacteria burst and virus is release to the environment. The word lytic comes from the Latin which means to burst open

 

  1. b) A lysogenic cycle.

Much like the lytic cycle the host bacteria is infected by the virus, however lyses of the bacteria does not happen immediately. Bursting of the cell only occurs when the bacteria become weakened or there is a change in the environment.

 

 

Retrovirus Infections:

  • A retrovirus is a RNA virus which infects the host in a unique fashion.
  • The viral RNA serves as a template for the host cell to make a segment of DNA.
  • This DNA is then encoded into the host’s genetic material.
  • The cell does not die but changes due to the new encoded material.
  • The mechanisms of this type of infection are still being researched.

Question Seven: Are all infections the same?

The answer is no. There are at least three possible outcomes from an infection:

Results of viral infection can be:

  1. A virulent infection:
  • This is when the virus causes a lytic cycle and the host cell dies

 

  1. A latent infection:
  • This is when the virus either becomes part of host genome or remains dormant until changes in host cell and or external environment.

 

  1. Tumour producing infection:
  • This is when the host cell is not destroyed but mutated causing the host cell to divide and produce cluster of cells that have changed from the original cell. If these cells remain dormant they are said to be benign and show themselves as a wart or tumour), if these cells become mobile, they are said to be malignant.

 

Question Eight: What diseases are caused by viral infections?

  • Some common viral infections are:

viral pneumonia,            the common cold,   influenza,       mumps,         measles, German measles         polio                           shingles      chickenpox    smallpox, AIDS virus                       hepatitis                    warts              yellow fever   cold sores hoof and mouth disease      Ebstein Barr virus                mosiacs in plants

 

  • May be associated with some cancers, leukaemia’s, and autoimmune disorders
  • Some lethal viruses: Ebola (95% fatality rate)
  • Most publicised virus: HIV

 

 

Question Nine: Is there a way to treat or cure viral infections?

  • One of the first methods of preventing infection by virus was done by the Chinese, who rubbed other individuals with skin scabs from those individuals who survived a viral infection such as small pox.
  • Edward Jenner, created a process called vaccination ( from the Latin origin vaca for cow : another famous cow story!) by exposing individuals to cowpox virus, which he noted prevented them from being infected from a more virulent virus for small pox.
  • It is useless to treat a viral infection with antibiotics however people treated with a killed strain of virus or viral proteins may create their own antibodies to attack onto viral proteins.

 

Question Ten: How were virus discovered?

 

  • Discovery of virus were initially related to nature of infection of hosts
  • Actual viral material viral material was not purified until 1933 by Stanley. This particular material was crystallise tobacco mosaic.
  • Identification of viruses has improved with the increased efficiency of electron microscopes.
  • Because viral DNA/RNA interacts with host nucleic material, viruses are continue to change and evolve.

 

If you have any further questions you wish to explore

posted by Marc Bernard Carmichael in Biology Eleven,Biology Eleven Notes,Microbio,Microbio and have No Comments