SNC4M - Bacteria unit

Archaebacteria

Archaebacteria

Ancient bacteria

Eubacteria

Modern bacteria

Where archaebacteria are found

Extreme conditions

Pili

Part of bacteria cell that is responsible for sexual conjugation

Autotrophs

Can prepare their own food “producers”

Heterotrophs

Consumers, need to consume their food

Chemosynthetic bacteria

gets energy from chemical reactions

Photosynthetic bacteria

bacteria that can photosynthesize

Parasitic bacteria

bacteria that can get nutrients from a host

Saprophytic

“decomposer” bacteria that feeds on decaying matter

Crystal Violet (gram staining)

Stains peptidoglycan layer purple

Iodine (gram staining)

“sets” crystal violet stain

Ethanol (gram staining)

dissolves crystal violet

Safranin (gram staining)

stains gram negative bacteria pink

Binary fission

asexual reproduction

Advantage of binary fission

bacteria can multiply very fast

Disadvantage of binary fission

no variety, can all be killed if doesnt mutate

Method 1 for bacteria to cause disease

Binary fission

Method 2 for bacteria to cause disease

Getting inside a host cell using invasins, protects the cell from antibodies and complements

Method 3 for bacteria to cause disease

Toxins (endo and exo)

Endotoxins

• Macrophage engulfs endotoxic bacteria, bacteria releases endotoxins

• Macrophage releases cytokines

• Cytokines travel to hypothalamus

• Cytokines cause fever

Exotoxins

• Bacteria produces exotoxins

• Inhibits protein synthesis

• B component is released from host cell to infect more host cells

More dangerous toxin

Exotoxin

Less dangerous toxin (unless it spreads)

Endotoxin

Disease caused by endotoxins

Typhoid fever

Diseases caused by exotoxins

Diphtheria and tetanus

Iron tug of war

Macrophages and bacteria both need iron to reproduce

Complements

Proteins made by liver, forms MAC (membrane attack complex)

Classical pathway

happens when combined with antibodies that are attached to antigens after humoral response

Alternative pathway

spontaneously happens, doesnt need humoral response

Chain of infection target 1

Susceptible host

Chain of infection target 2

Means of transmission

Chain of infection target 3

Reservoirs

Plasmids

small subsets of DNA

DNA vaccine

makes fake antigen marker for an immune response

Endospores

DNA surrounded by thick wall, can create a new cell up to 50 years later

how antibiotics work

kills microbe, inhibits reproduction

Conjugation

creation of new bacterial cells through plasmid creation/transfer , need to have a mate

CRISPR

gene editing tool

Quorum sensing

Way of communication to let bacteria know that there are enough of them to act on a cell

Biofilm

lots of bacterium stuck together so they arent wiped out as easily