Micro-Unit 1 – Flashcards

• [image][image][image][image]knowledge of microorganisms
• allows humans to prevent food spoilage & disease occurance
• led to aseptic techniques to prevent contanimation in medicine and microbiology labs
• helps us to read/understand lab reports so that we can better assist Dr. & patients & protect ourselves as nurses

• discovered relationship between microbes & disease, immunity and antimicrobial drugs
• Ended the debate over Spontaneous Generation
• demonstrated that spoilage bacteria could be killed by heat (pasteurization is the application of a high heat for a short time)

• showed that microbes are in the air and can spoil food and cause diseases
• used a chemical disinfectant to prevent surgical wound infections

• Microbial Ecology- bacteria recycle carbon, nutrients, sulfu ; phosphorus that can be used by plants ; animals
• Bioremediation- Bacteria degrade organic matter in sewage, bacteria degrade or detoxify pollutants such as oil and mercury.
• Biological Insecticides- microbes that are pathogenic to insects ; alternatives to chemical pesticides (Bacillus thuringiensis)
• Biotechnology- the use of microbes to produce foods and chemicals
• Biotechnology- recombinant DNA technology enables bacteria and fungi to produce a variety of proteins including vaccines and enzymes

(genus + specific epthet)

can be used world wide

• Prokaryotes- single cells with no defined nucleus
• Peptidoglycan cell walls
• Divide by binary fission
• use organic chemicals, inorganic chemicals or photosynthesis for energy

• Prokaryotic
• Lack peptidoglycan
• Live in extreme environments
• Include-
• Methanogens
• Extreme Halophiles
• Extreme thermophiles

• eukaryotic cells which have a defined visible nucleus and divide by mitosis
• Kingdoms

Variations within a species are called:

Types- usually a serological designation

Strains- usually a biochemical or morphological

• Acellular- not cells
• Consist of DNA or RNA core
• Core is surrounded by a protein coat- capsid
• Coat may be enclosed in a lipid envelope
• Viruses are replicated only when they are IN a living host cell- obligate intracellular paracites

at one or both poles or ends of a cell

coccus

bacillus

spiral

diplococci (pair)

streptococci (chainlike)

tetrads (4)

sarcinae (cubelike groups of 8)

staphylococci (grapelike clusters)

Diploblaccilli (2)

Streptobacilli (chains)

coccobacilli (look like cocci & are rare)

Vibrios (curved rods)

Spirilla (helical shape & rigid)

spirochetes (helical & flexible, have an axial filament for movement)

sugar coating surrounding cells

viscous & sticky

• The glycocalyx that is organized and firmly attached to the cell wall
• Determined by gram staining
• Used for protection against phagocytes
• formation of biofilms come from this layer

• Found in all bacterial cells
• made up of phospholipids & proteins
• no carbs & usually no sterols
• used for transport of chemicals in and out of cell & carries out functions concerning cellular respiration and other enzymatic activities

Only found in spirochetes

anchored at one end of a cell

rotation causes movement (think corkscrew or barber pole)

• can occur at the poles or be evenly distributed over a bacterial cell
• a few to several hundred per cell
• adhere to each other and surfaces

• longer than fimbriae
• only 1 or 2 per cell
• involved in motility & DNA transfer

• Composition of a bacterial cell wall
• Polymer of disaccharide (NAG & NAM are connected & alternate) The chains are bonded by peptides

thick, rigid layer of peptidoglycan

contain teichoic acid (look like a long, black hair)

"built like a wall"

• Thin layer of peptidoglycan & outer membrane on wall
• periplasm forms between the outer membrane & plasma membrane, making it hard to get antibiotics through
• peptidoglycan is bonded to lipids in the outer membrane
• "Built like a patio"

• Acid-fast cell walls with no outer membrane
• contains waxy lipid bound to the peptidoglycan, making it resistent to drying
• Mycobacterium (TB) & Nocardia are examples

Flagella

Axial Filaments

Fimbriae

Pili

Induces an immune response in a host

(our body will view it as foreign and threatening)

Capsule (in some)

Cell Wall (in most)

Plasma Membrane (in all)

Nucleoid

Plasmid

Ribosomes

Inclusion

Endospores

• singular piece of double stranded DNA
• controls all activities of cell
• DNA--->RNA--->Protein
• DNA--->DNA (replicates for reproduction)

• small extra chromosmal piece of circular DNA 5-100 genes long
• for adaptation- can carry genes for drug resistance used in recombinent DNA technology

• RNA and protein (70S)
• site of protein synthesis (RNA--->protein)

• phosphate granules, starch, lipid, sulfur
• used for storage

• condensed, dormant cell stage containing all vital cell components
• survival is key function