Bell Ringer What happens when you get sick? What are symptoms you get when youre sick? Give three examples…

Prokaryotes Video Or 100 Trillion Friends That You Didn’t Know You Had Another video Bozeman Science https://www.youtube.com/watch?v=h-z9-9OOWC4

The Human Microbiome We are actually a giant ecosystem of microbes Prokaryotes comprise between 1-3% of the mass of a human body - up to 6lbs of a 200 lb person can be microbes

Bacteria Earth’s oldest life forms – between 3.5 and 3.8 billion years old Most abundant life form – up to 2.5 billion individual bacteria in 1 gram of fertile soil Very adaptable – found in all of Earth’s ecosystems 4

Bacteria Characteristics Unicellular Circular DNA, No organelles 1/10th the size of eukaryotic cells Flagella-long hair-like structure used for movement Reproduce asexually –Binary Fission 5

Reproduction - Binary Fission Bacterial cells undergoing binary fission 6

Bacterial Roles: Symbiotic Bacteria Many bacteria live in or on other organisms (including humans) and aid their host - some live in the gut of herbivores helping to digest cellulose - bacteria in the gut of humans aid digestion and produce vitamins - bacteria on skin and in body openings help prevent infection by harmful organisms Stomach bacteria help maintain stomach pH, produce B and K vitamins, studies show that babies given lactobacilius bacteria have less diarrhea

Bacterial Roles: Pathogenic Bacteria Pathogens are organisms that cause disease - only a small portion of bacteria are pathogens - most bacteria diseases are caused by toxins released by the bacteria - these toxins: - poison cells and damage tissue - interfere with cell signaling - over-stimulate cells causing them to malfunction

Antibiotics Antibiotics are chemicals which either kill bacteria or prevent their growth and reproduction The discovery of antibiotics revolutionized the treatment of disease Antibiotics which kill bacteria are bacteriacidal, the antibiotics which stop growth are referred to as bacteriastatic

Antibiotic Resistance Some bacteria have developed a resistance to the effect of some antibiotics NOT KILLED BY ANTIBIOTICS - the number of resistant bacteria is growing The problem is increased by overuse and misuse of antibiotics - use of antibiotics to treat viral infections – antibiotics don’t effect viruses!!! kills the most susceptible bacteria, but leaves the more resistant bacteria

Streptococcus Bacteria that causes Strep throat

Black Plague-Yersinia pestis Bacillus bacterium from flea bites that recently fed on infected rats. Flea regurgitates germs onto human open wound. Sign of infection is lymph nodes swellings called Buboes. Dried blood under the skin turns black, hence the name Black Death. Spread is slow from person to person. Mortality is very high (75%) for untreated cases. Now early treatment with antibiotics is very effective. 12

Syphilis--Treponema pallidum/Bacterial Causes an ulcer at the site of infection. 4 stages of life. Treatment now with Penicillin. 13

Mycobacterium leprae/Bacteria Rod like Bacteria-spread through coughing and sneezing. In old days they thought it was genetic and they isolated people-Leprae colonies. Now (1940)there is antibiotic treatment to clear up the symptoms in 6-12 months. 14

Clostridium perfringes/Bacteria Gram positive bacillus. Can cause gas gangrene. Often caused from fecal contamination of a wound Usually in the buttocks, thighs, and perineum. Infection may proceed up to 10cm per hour. Often produces large amounts of CO2 and hydrogen . 15

Bacterial Shapes 3 main shapes - coccus – sphere - bacillus – rods - spirillum - spiral

Bacterial Structure Cell Wall Cell Membrane Pilus chromosome nucleoid capsule ribosome plasmid cytoplasm flagellum

Bell ringer Do antibiotics cure a viral infection? Why?

Virus Video Definition: Non living particle made up of nucleic acid, protein, and in some cases lipids that can replicate only by infecting living cells

Characteristics of Viruses Intercellular Parasite - Must replicate inside a host Mutate Rapidly Host Specific Small – from 20nm to 250nm Replication: VIDEO Lytic Cycle- cell explodes releasing viral DNA Lysogenic Cycle- cell replicate with viral DNA inside host 20

Vaccinations Facts and Fiction READ… Inoculation (shot) that renders recipient immune to the virus. - Preventative care

Small Pox- Lytic Jenner developed first vaccine 1798 Small pox virus can only live in humans. Spread person to person generally through close contact with infected person. Symptoms appear 12 –14 days after exposure. 1st symptoms are fever, tiredness, severe back pain, stomach pain and vomiting. This last 2-3 days and at this time the person is highly contagious to others.Then over the next 5 days the bumps appear. Today we have a vaccine for small pox. We have 15.5 million doses available now. A contract has been made to produce 210 million does this year!! Today the risk of the disease is less than the risk from the vaccine so people do not get vaccinated. Vaccine can be helpful if you are exposed up to 4 days after exposure. 23

Herpes Simplex 1/Lysogenic 24

Shingles-Lysogenic/ Chicken pox virus (herpes varicella-zoster) Shingles is caused by the chicken pox virus. It can develop in anyone who has had chicken pox. The chicken pox virus remains dormant or inactive (lysogenic cycle) in nerve root cells of the body. Shingles is the second outbreak of the chicken pox virus. Usually happens in older people (65) because of weakened immune system.Typical case of shingles lasts about a month. If you get it on your face you should see a physician because it can led to blindness. 25

AIDS/HIV

Zika

West Nile

Yellow Fever

Measles, Mumps, Rubella

Virus Structure Helical virus – hollow tube of protein, icosahedron, phage 31

Structure - Nucleic Acid – DNA or RNA - Protein coat – called a capsid Envelope – some contain a layer of membrane taken from a host cell - Glycoproteins- identify and bind to receptor sites on the host's membrane

Bacteriophage Bacteriophages are viruses that infect bacteria - they are responsible for transduction in bacteria 33

Bell Ringer What are the three bacterial shapes? How do people prevent catching a virus?