Bacteria and VirusesBacteria and Viruses

Ingle/EbenerIngle/Ebener

(R/H/M)(R/H/M)

Kingdom Eubacteria

No organelles

Can be different shapes:

a. coccus: round

b. bacillus: rod shaped

c. spirillum: spiral

Arrangements:

a. diplo: pairs

b. staphylo: clusters

c. strepto: long chains

Transmitted through air, water, human contact, contaminated foods.

Adaptations for survival

1. Endospores

a. hard outer covering produced during harsh environments.

b. resistant to drying out, and boiling

c. metabolism slows down, resumes growing when conditions

are more favorable.

D. sterilized under pressure (autoclave)

2. Toxin production

a. poisons produced when endospore begins to grow

b. some are deadly

Examples: botulism, tetanus

Types of Bacterial ReproductionTypes of Bacterial Reproduction1. Binary Fission1. Binary Fission

a. asexually-splitting in half a. asexually-splitting in half after copying genetic material-after copying genetic material-happenshappensquickly quickly

b. Stops reproducing only if they b. Stops reproducing only if they run out of food, dry up, run out of food, dry up, poisoned by wastes poisoned by wastes

2. Conjugation2. Conjugationa. sexual reproduction a. sexual reproduction

transferring all or part of DNAtransferring all or part of DNAb. transfer occurs from one b. transfer occurs from one

bacteria to anotherbacteria to another

Immune Response

1. The immune system fights off invaders: Antigens

2. Our bodies produce Antibodies against each antigen

a. antibodies: lock on to pathogen’s active site or prevent its’ attachment

Tooth decay

Lyme disease

Tetanus

Tuberculosis

Salmonella food poisoning

Pneumonia

Cholera

Streptococcus mutans

Borrelia burgdorferi

Clostridium tetani

Mycobacterium tuberculosis

Salmonella enteritidis

Streptococcus pneumoniae

Vibrio cholerae

Regular dental hygiene

Protection from tick bites

Current tetanus vaccination

Vaccination

Proper food-handling practices

Maintaining good health

Clean water supplies

Disease Pathogen Prevention

Section 19-2

Common Diseases Caused by Bacteria

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3. Immunity: resistance to a disease

A. passive immunity: antibodies are acquired, passed from mother to child or injection of antibodies.

B. active immunity: exposed to the antigen, from recovery of the disease

C. vaccination: injection of weakened pieces of antigen

Uses for Bacteria

1. Nitrogen fixation:a. some convert nitrogen gas into

nitrates in the soil used by plants

2. Saprobes:a. break down dead organic

matter

3. Food flavorings: a.produced by fermentation

b. vinegar, yogurt, butter, cheese, pickles, buttermilk

4. Antibiotic production:

a. antibiotics kill bacteria only

b. some bacteria produce antibiodies that will kill other forms of bacteria

5. Recombinant DNA technology

Helpful BacteriaHelpful Bacteria

NITROGEN FIXATION:NITROGEN FIXATION: Some bacteria convert Some bacteria convert

nitrogen gas into nitrogen gas into nitrates in the soil which nitrates in the soil which is necessary for plant is necessary for plant growthgrowth

SAPROBES:SAPROBES: Break down dead Break down dead

organicorganic mattermatter

Helpful BacteriaHelpful Bacteria FOOD FLAVORINGS:FOOD FLAVORINGS: Food flavors are produced Food flavors are produced

by fermentation, bacterial by fermentation, bacterial wastes, etc.wastes, etc.

Vinegar, yogurt, butter, Vinegar, yogurt, butter, cheese, pickles, cheese, pickles, buttermilk, sauerkrautbuttermilk, sauerkraut

ANTIBIOTIC PRODUCTION:ANTIBIOTIC PRODUCTION: Some bacteria produce Some bacteria produce

antibiotics that will kill antibiotics that will kill other forms of bacteriaother forms of bacteria

Antibiotics kill bacteria Antibiotics kill bacteria onlyonly

Helpful BacteriaHelpful Bacteria

help clean-up oil help clean-up oil spillsspills

Works in Landfills Works in Landfills to break down to break down wastes (including wastes (including some hazardous some hazardous wastes)wastes)

Waste- water Waste- water treatment plantstreatment plants

Helpful Bacteria- Our bodiesHelpful Bacteria- Our bodies

1.1. Provide Vitamin K (E coli)-clots blood & Provide Vitamin K (E coli)-clots blood & keeps bones strongkeeps bones strong

2.2. Keeps invading bacteria, viruses, & yeast Keeps invading bacteria, viruses, & yeast in check. Antibiotics can destroy friendly in check. Antibiotics can destroy friendly bacteria (women/ yeast infections after bacteria (women/ yeast infections after taking antibiotics)taking antibiotics)

3.3. Makes Lactase-enzyme needed to break Makes Lactase-enzyme needed to break down dairy productsdown dairy products

Harmful Bacteria- RespiratoryHarmful Bacteria- Respiratory

1.1. Strep Throat-Strep Throat- infection of infection of pharynx with pharynx with Streptococcus.Streptococcus. Spread-nasal or salivaSpread-nasal or saliva

2.2. Sinusitis-Sinusitis- inflammation of inflammation of sinuses(hollow spaces within sinuses(hollow spaces within the bones around your nose)the bones around your nose)

3.3. Pertussis- Whooping Cough-Pertussis- Whooping Cough-like cold except coughing like cold except coughing spells. spells. Bordetella pertussisBordetella pertussis

Harmful Bacteria- Harmful Bacteria- Pneumonia-Pneumonia-inflammation of lungs(can be inflammation of lungs(can be

from a bacteria, virus, or fungus). from a bacteria, virus, or fungus).

Conjunctivitis “Pink Eye ” Conjunctivitis “Pink Eye ” Infects outermost layer of Infects outermost layer of

eye(Conjunctiva)eye(Conjunctiva) can be viral(cold) or bacterial(staph or can be viral(cold) or bacterial(staph or

strep), or allergies strep), or allergies ContagiousContagious

Harmful Bacteria- DigestiveHarmful Bacteria- Digestive1.1. Stomach Virus (24 hour)- many times it is not a virus but Stomach Virus (24 hour)- many times it is not a virus but

a bacteria from food poisoning.a bacteria from food poisoning.

2.2. Botulism- Botulism- Food poisoning- Food poisoning- Clostridium botulinum; Clostridium botulinum; endospore, endospore,

a. infants- don’t give homemade honey ; canning (boil a. infants- don’t give homemade honey ; canning (boil at high temp)at high temp)

b. Pasteurization- heating process to prevent b. Pasteurization- heating process to prevent contamination of milk.contamination of milk.

3. Salmonella enterocolitis- infection in small intestine by 3. Salmonella enterocolitis- infection in small intestine by

Salmonella bacteria. Any food can have it.Salmonella bacteria. Any food can have it.

Harmful Bacteria-SkinHarmful Bacteria-Skin1.1. Diaper RashDiaper Rash- bacteria from feces- bacteria from feces

2.2. Scarlet Fever- Scarlet Fever- skin rash- group A skin rash- group A streptococcistreptococci

3.3. AcneAcne- oil blocks & bacteria grow- oil blocks & bacteria grow

Harmful Bacteria-(TB)TuberculosisHarmful Bacteria-(TB)Tuberculosis Attacks lungsAttacks lungs Spreads through airSpreads through air Close contact neededClose contact needed You can be exposed to it but not get the You can be exposed to it but not get the

diseasedisease Skin Test to detectSkin Test to detect Making a “comeback” in developed countriesMaking a “comeback” in developed countries

Harmful Bacteria- The PlagueHarmful Bacteria- The Plague

Yersinia pestis-Yersinia pestis- in wild rodents/ in wild rodents/ flea bitesflea bites

Spread by bites or infected Spread by bites or infected person coughingperson coughing

Pneumonia or BubonicPneumonia or Bubonic

Harmful Bacteria- AnthraxHarmful Bacteria- Anthrax

Bacillus anthracisBacillus anthracis Spore-formingSpore-forming Occurs in cattle, sheep, humansOccurs in cattle, sheep, humans Inhale it or handle contaminated animal Inhale it or handle contaminated animal

productsproducts Symptoms show within 7 daysSymptoms show within 7 days

Lyme Disease-Harmful Lyme Disease-Harmful BacteriaBacteria Borrelia burgdorferi- transferred Borrelia burgdorferi- transferred

by a deer tickby a deer tick Skin rash, inflammation, flu-like Skin rash, inflammation, flu-like

symptomssymptoms

Harmful Bacteria- Harmful Bacteria- LeprosyLeprosy

Skin lesions , nerve damageSkin lesions , nerve damage Mainly 3Mainly 3rdrd world countries world countries Difficult to transmitDifficult to transmit 100 cases a year in U.S.(south, Ca, 100 cases a year in U.S.(south, Ca,

Hawaii)Hawaii) Have medicine now to treatHave medicine now to treat

Characteristics of Characteristics of a Virusa Virus

Tiny, Tiny, non-livingnon-living particles Do particles Do not respire, move or grownot respire, move or grow

Cannot reproduce on their ownCannot reproduce on their own Must reproduce inside of a Must reproduce inside of a

host cellhost cell Typical infection lasts 7-10 Typical infection lasts 7-10

daysdays Not given Latin names: named Not given Latin names: named

for disease caused, organ for disease caused, organ infected, or region detected in infected, or region detected in

Viral Viral StructureStructure

All viruses consist of 2 basic All viruses consist of 2 basic parts: parts:

1. nucleic acid (DNA or RNA)1. nucleic acid (DNA or RNA)

2. outer Protein coat= 2. outer Protein coat= CapsidCapsid

Protein coat gives viruses Protein coat gives viruses different shapesdifferent shapes

Attachment site: where a Attachment site: where a virus attaches to a cell. “tricky virus attaches to a cell. “tricky invader”invader”

Viral recognition Viral recognition and attachment and attachment Virus must recognize specific Virus must recognize specific

receptor site on host cellreceptor site on host cell Part of virus matches site on hostPart of virus matches site on host Lands on host and “locks in”Lands on host and “locks in” Attachment is specific: virus can Attachment is specific: virus can

enter and reproduce in only a few enter and reproduce in only a few types of cellstypes of cells

Ex. HIV- WBCEx. HIV- WBC

Ex. Flu- Respiratory tractEx. Flu- Respiratory tract

Ex: tobacco mosaic virus- Ex: tobacco mosaic virus- tobacco plant Ex. T4 Bacteriophage- tobacco plant Ex. T4 Bacteriophage- virus that infects bacteriavirus that infects bacteria

Viral reproductionViral reproduction

must reproduce inside of a host cellmust reproduce inside of a host cell classified as intracellular parasitesclassified as intracellular parasites The method of entry into the host cell The method of entry into the host cell

depends on the virusdepends on the virus Some viruses inject DNA, some indent Some viruses inject DNA, some indent

cell irritating cell until it engulfs itcell irritating cell until it engulfs it There are two main types of viral There are two main types of viral

reproduction:reproduction: Lytic cycle and lysogenic Lytic cycle and lysogenic cyclecycle

Steps of the Lytic Steps of the Lytic cycle.cycle. AttachmenAttachment:t: virus virus

attaches to cellattaches to cell EntryEntry:: injects DNA and injects DNA and

takes over host takes over host nucleusnucleus

ReplicationReplication:: reproduces virus partsreproduces virus parts

AssemblyAssembly: puts virus : puts virus parts togetherparts together

Lysis and releaseLysis and release: : cell bursts open cell bursts open releasing viruses; cell releasing viruses; cell diesdies

Ex. Flu, ColdEx. Flu, Cold

Lysogenic cycleLysogenic cycle Lysogenic cycle: viruses attack cells, but do Lysogenic cycle: viruses attack cells, but do

not kill cell immediatelynot kill cell immediately Viral DNA is mixed with host DNA like lytic Viral DNA is mixed with host DNA like lytic

cyclecycle Does not immediately begin to reproduce, host Does not immediately begin to reproduce, host

may function normally (virus lies dormant)may function normally (virus lies dormant) Example: Herpes (cold sores, fever blisters)Example: Herpes (cold sores, fever blisters)