Micro-life: BacteriaMicro-life: BacteriaYou will understand and You will understand and

comprehend the comprehend the characteristics of bacteriacharacteristics of bacteria

Bacteria Characteristics:Bacteria Characteristics:

LIVING Single Celled LIVING Single Celled organismsorganismsContain DNA and RNA Contain DNA and RNA genetic materialgenetic materialMost have a cell wall Most have a cell wall (protective layer)(protective layer)May have a capsule May have a capsule around cell wall (most around cell wall (most disease causing do)disease causing do)Have small hair like Have small hair like extensions called Pilus extensions called Pilus (i)(i)May produce an May produce an ENDOSPORE when ENDOSPORE when placed in unfavorable placed in unfavorable conditionsconditions

3 Forms of Bacteria3 Forms of Bacteria

3 basic forms3 basic forms

Cocci- RoundCocci- Round

Bacillus- Rod Bacillus- Rod ShapedShaped

Spirilla- “Curly Spirilla- “Curly Fries”Fries”

Bacteria Needs and Bacteria Needs and ReproductionReproduction

Bacteria need moisture, food source Bacteria need moisture, food source and warm in general to growand warm in general to grow

Lungs, Mouth, and Nasal Passages are Lungs, Mouth, and Nasal Passages are ideal growing places for bacteriaideal growing places for bacteria

Body’s production of mucus with Body’s production of mucus with enzymes helps prevent bacteria from enzymes helps prevent bacteria from growinggrowing

Bacteria reproduce rapidly when Bacteria reproduce rapidly when needs are metneeds are met

Bacteria Reproduction: 2 Bacteria Reproduction: 2 waysways

Fission (asexual/cloning)- Fission (asexual/cloning)- Bacteria simply makes Bacteria simply makes duplicate copies if genes duplicate copies if genes and divides. DNA is and divides. DNA is exact same for both exact same for both parent and “daughter parent and “daughter cell”cell”

Fusion (sexual)- Bacteria Fusion (sexual)- Bacteria exchanges genetic exchanges genetic material with another material with another bacterium. DNA is bacterium. DNA is different than “Parent” different than “Parent” bacterium. bacterium.

2 Types of Bacteria2 Types of Bacteria

Archaebacteria- Archaebacteria- “Extremeophiles” live “Extremeophiles” live in harsh environments, in harsh environments, deep sea, deep deep sea, deep underground, volcanic underground, volcanic areas: DO NOT NEED areas: DO NOT NEED OXYGEN TO SURVIVE: OXYGEN TO SURVIVE: Autotrophs-make their Autotrophs-make their own food (light)own food (light)Eubacteria- found Eubacteria- found commonly commonly everywhere: everywhere: Heterotrophs- need Heterotrophs- need food source to livefood source to live

Common Diseases from Common Diseases from BacteriaBacteria

Anthrax, Botulism, Anthrax, Botulism, Tetanus, Typhoid Tetanus, Typhoid fever, Rocky fever, Rocky Mountain Spotted Mountain Spotted fever, Syphilis, fever, Syphilis, Gonorrhea, Gonorrhea, Pneumonia, Strep Pneumonia, Strep ThroatThroat

Medicines made by bacteriaMedicines made by bacteria

Insulin, Insulin, amikacin, gentamicin, , gentamicin, kanamycin, neomycin, netilmicin, kanamycin, neomycin, netilmicin, paromomycin, streptomycin, paromomycin, streptomycin, tobramycin and apramycin and tobramycin and apramycin and antifungal medicinesantifungal medicines

Also being looked as possible source Also being looked as possible source to fight cancer(?)to fight cancer(?)

Foods made with bacteria aid, pickles, Foods made with bacteria aid, pickles, vinegar, yogurt, and cheesevinegar, yogurt, and cheese

BIG PROBLEMBIG PROBLEM

Overuse of antibiotics has Overuse of antibiotics has lead to “Super strains” of lead to “Super strains” of bacteria to “evolve”bacteria to “evolve”

Very hard to kill bacteria Very hard to kill bacteria that cause MRSA or that cause MRSA or STAPH infectionSTAPH infection

MOST HOSIPTALS MOST HOSIPTALS HAVE THESE HAVE THESE SUPERSTRANDS within SUPERSTRANDS within them!them!

Population ExplosionPopulation Explosion

Suppose a bacterium Suppose a bacterium reproduces by binary reproduces by binary fission every 20 fission every 20 minutes. The new cells minutes. The new cells survive and reproduce survive and reproduce at the same rate. This at the same rate. This graph shows how the graph shows how the bacterial population bacterial population would grow from a would grow from a single bacterium.single bacterium.

- Bacteria

Population Population ExplosionExplosion

Horizontal axis–time Horizontal axis–time (minutes); vertical axis–(minutes); vertical axis–number of bacterial cells.number of bacterial cells.

Reading Graphs:Reading Graphs:

What variable is being What variable is being plotted on the plotted on the horizontal axis? What horizontal axis? What is being plotted on the is being plotted on the vertical axis?vertical axis?

- Bacteria

Population Population ExplosionExplosion

2 cells after 20 minutes;2 cells after 20 minutes;8 cells after one hour;8 cells after one hour;64 cells after two hours.64 cells after two hours.

Interpreting Data:Interpreting Data:

According to the According to the graph, how many cells graph, how many cells are there after 20 are there after 20 minutes? One hour? minutes? One hour? Two hours?Two hours?

- Bacteria

Population Population ExplosionExplosion

The number of cells The number of cells doubles with each division.doubles with each division.

Drawing Conclusions:Drawing Conclusions:

Describe the pattern Describe the pattern you see in the way the you see in the way the bacterial population bacterial population increases over two increases over two hours.hours.

- Bacteria

Population Population ExplosionExplosion

Not likely. The bacteria will Not likely. The bacteria will continue to reproduce at this continue to reproduce at this rate only as long as the rate only as long as the conditions are favorable.conditions are favorable.

Predicting:Predicting:

Do you think the Do you think the bacterial population bacterial population will continue to grow at will continue to grow at the same rate? Why or the same rate? Why or why not?why not?

Drawing The Bacterial CellDrawing The Bacterial CellBacteria are Bacteria are

prokaryotes. prokaryotes. The genetic The genetic material in the material in the cells is not cells is not contained in a contained in a nucleus.nucleus.

- Bacteria

How your body responds to the How your body responds to the “Bacterial INVASION”“Bacterial INVASION”

Natural Killer Cells arrive and attack bacteriaNatural Killer Cells arrive and attack bacteriaB cells release antibodies that can smother the B cells release antibodies that can smother the bacteria, not allowing it to move (B cells must bacteria, not allowing it to move (B cells must recognize bacterial coating, so you need a past recognize bacterial coating, so you need a past “encounter”/infection) “encounter”/infection) MACROPHAGES come and eat the invader MACROPHAGES come and eat the invader creating a fever and more immune cellscreating a fever and more immune cellsAntibiotics help accelerate the process killing Antibiotics help accelerate the process killing bacteria and promoting a quicker response by bacteria and promoting a quicker response by the body’s immune systemthe body’s immune system