Bacteria

Bacteria

1. Structure: all microscopic, unicellular or colonial Prokaryotic (lack true nucleus)

Bacteria

1. Structure: all microscopic, unicellular or colonial Prokaryotic (lack true nucleus) Bacillus (rods) Coccus (spherical) Spirilla (spiral) Most immobile, few with flagella

Bacteria

Rod-Shaped Bacteria

On the head of a pin!

Magnified 25,000 times!

Bacteria

2. Reproduction asexual by fission (simple cell division, divide into

two equal sizes (every 20 min.) Sexual by conjugation 3. Physiology Autotrophic, parasitic, saprophytic (live on dead

organisms) Aerobic (use oxygen) and anaerobic (don’t use

oxygen4. Where do they live? EVERYWHERE

Bacteria are found in Geyser Hot Springs

Black Rock Desert,

Nevada.

Temperatures just below boiling - colors are the result of various bacterial colonies.

Bacteria

5. Diseases (more examples to follow) Tetanus, TB, cholera, bubonic plague,

syphilis, typhoid, anthrax, pneumonia, diptheria, strep throat, salmonella, botulism,

6. Benefits Organic decay, antibiotics, yogurt, cheese,

support life in hydrothermal vents.

Leprosy: caused by a bacterial infection

Normal tissue in the center

Infected tissue on the left

Leprosy

Affected hands shown here.

Leprosy Again.

Impetigo

Highly contagious childhood disease

Bacterial infection that leaves scabs and pigment loss

Gonococcal Bacterial Infection of the Eye

Most common in newborns who are infected as they pass through the birth canal

Adults can transfer the bacteria to the eye from the genitals

Gangrene

Caused by anaerobic bacteria whose toxins kill tissue

Amputations are common

Can be lethal if not treated

Strep Throat

Bacterial infection most common in 5-15 year olds

Tonsils swell with pus-filled lesions

Strep Throat Again

Pus-filled lesions on the tonsils

Diptheria (bacterial infection)

Less than 10 cases per year in the USA

Bacteria form a membrane that causes bleeding and blocks the airway

Infected Lung Cell

Infected (via adhesion)by numerous mycoplasma bacterium

This is the bacteria that causes pneumonia

Advanced Periodontal Disease

Severe gum inflammation

Caused by a bacterial infection

Salmonella typhic (bacterium)

Causative agent of typhoid (rare in USA)

Bacteria invade upper intestine causing nausea and headaches - lasting 4-5 weeks

Anthrax Lesion (Bacterial Infection)

Sheep wool is often the carrier

Warning: Next Slide fairly graphic

Necrotizing Subcutaneous Infection (Necrotizing Fasciitis NF)

Caused by a bacterial infection - commonly referred to as “Flesh Eating Bacteria”

Bacteria release toxins that directly kill tissue

NF Again

Although rare, the bacteria can be found almost everywhere - once infected tissue loss is rapid

Shock and death are possible

NF Again

Requires large-scale tissue removal and heavy doses of antibiotics

The End

Remember bacteria are everywhere!

Wash your hands often!