Busy. Please wait.

Forgot Password?

Don't have an account?  Sign up 

show password


Make sure to remember your password. If you forget it there is no way for StudyStack to send you a reset link. You would need to create a new account.

By signing up, I agree to StudyStack's Terms of Service and Privacy Policy.

Already a StudyStack user? Log In

Reset Password
Enter the email address associated with your account, and we'll email you a link to reset your password.

Remove ads
Don't know (0)
Know (0)
remaining cards (0)
To flip the current card, click it or press the Spacebar key.  To move the current card to one of the three colored boxes, click on the box.  You may also press the UP ARROW key to move the card to the "Know" box, the DOWN ARROW key to move the card to the "Don't know" box, or the RIGHT ARROW key to move the card to the Remaining box.  You may also click on the card displayed in any of the three boxes to bring that card back to the center.

Pass complete!

"Know" box contains:
Time elapsed:
restart all cards

Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.

  Normal Size     Small Size show me how

Microbiology 1

1 Microbiology

3 Domains/classifications 1. Prokaryo 2. Archaea - strong type 3. Eukaryo
Structure of a Prokaryotic Cell 1. Small cells 2. No nuclear membrane - free floating DNA 3. Structures: appendages, cell envelope, cytoplasm
Structures of a Bacterial Cell 1. Prokaryotic organisms 2. Unicellular 3. Reproduces through binary fission
What is Binary Fission? Reproduction that ends up with 2 identical daughter cells
What does Binary Fission need in order to occur? - Sufficient amount of nutrients and a good environment (stops when no more nutrients)
How are bacteria cells classified? (2 things) 1. Shape 2. Arrangement
What shape is the Vibrios? Comma shaped rods
4 important cellular structures 1. Cell envelope (glycocalyx, cel wall, cel membrane) 2. Nuclear Body - genetic info 3. Endospores - how they evade antibiotics 4. Flagella/pilli - communication, mobility)
What are the 3 layers of a Cell Envelope 1. Glycocalyx 2. Cell Wall 3. Cell Membrane
Structures of the Glycocalyx (cell envelope) (2) - Pro 1. Polysaccharides - sticky sugar; help with attachment, communication, getting things from outside to in 2. Either Slime or Capsule layer
Functions of the Glycocalyx (cell envelope - outer) (5) - Pro 1. Communication between cells 2. Anchoring of cells 3. Formation of biofilms 4. Protection from pathogens 5. Involved in the immune system
Capsule - Thick, definite shape - Contributes to cell virulence (what allows a cell to cause a disease) - Protection from phagocytosis and drying - Immunogenic - can mount an immune response - Some vaccines directed at capsule
Slime layer - Thinner, less uniform - Protects agaisnt drying - Promotes adherence (cell-to-cell;surface) - e.g. oral bacteria and teeth
Cell Wall (2nd Layer of Cell Envelope) - Provides strength agaisnt osmotic pressure - Composed of peptidoglycan (PG) - determines Gram Stain
4 Steps of the Gram Stain 1. Apply crystal violet (purple dye) 2. Apply iodine to lock colour in 3. Alcohol wash 4. Apply safranin (red dye)
Structures of Gram Positive (6) 1. Peptidoglycan (PG) - 80-90% 2. Polysaccharides (sticky sugars) 3. Thick PG layer 4. No outer membrane 5. Narrow periplasmic space 6. More permeable to molecule
Structures of Gram Negative (7) 1. Lipopolysaccharide (LPS) 2. PG - 10-50% 3. Porin protein in wall 4. Thinner PG layer 5. Outer membrane 6. Extensive periplasmic space 7. Less permeable to molecules
Is LPS an Endotoxin? - Yes; an endotoxin is a toxin internal to bacterial cell, helps cause infection in host cell & more resistant
Cell Membrane (3rd layer of Cell Envelope) - made of? 1. Phospholipids - bilayer, heads pointing out (likes water) 2. Proteins 3. Glycolipids 4. Hopanoids - like cholesterol in humans
Functions of the Cell Membrane (4) 1. Structual support 2. Metabolic functions 3. Regulates transports 4. Role in immune response
Cytoplasm - Site of biochemical and synthetic activities (reactions occur, requires water) - 70-80% water - Solvent for cell nutrients - Contains cellular structures such as the nucleoid (single chromosom) and ribosoms
Nuclear Body - Single chromosome strand = nuceloid - No nuclear membrane - Free floating DNA
Plasmids - Extra chromosomal genetic info - Either free floating or in chromosome - Can be duplicated and passed onto offspring - Offers protective traits to bacteria
Ribosomes - Protein synthesis - Made of RNA and protein - Throughout cytoplasm and on cell membranes - Usually in chains (polysomes)
Endospores - Thick walled and resistance; purpose of survival
What are the 2 stages of endospores? 1. Vegetative Cell 2. Endospore
Vegetative Cells When environmental conditions are still good, putting energy into feeding and storing nutrients - When environmental conditions worsten = starts sporulation
5 Steps of Sporulation 1. Vegetative cell threatened 2. DNA copied & put towards end of cell (septation) 3. Sporangium engulfs forespore 4. Protective layer forms around 5. Sporangium deteriorates and releases spore
Germination = What is needed to reactivate the vegetative cell (4) 1. Nutrients 2. H2O and a germinating agent 3. Digestive enzymes; exposes core to H2O 4. Spore rehydrates and releases vegetative cell
Appendages - Allow for movement
Flagella - appendage - Whip like motion (like helicopter) - Composed of protein flagellin
3 Parts of a Flagella 1. Filament - end of whip; long and thin 2. Hook - at the end of flagellum, anchored to basal body 3. Basal Body - rod with 1+ pairs of disk
Arrangement of Flagella (4) 1. Monotrichous - single flagellum at one end 2. Lophotrichous - multiple flagellum from one end 3. Amphitrichous - both ends 4. Pertichous - all over surface
Periplasmic Flagella - Internal flagella; on spirochetes - 2 long coiled threads, inbetween cell wall and membrane - Twisting motion (like itsy bitsy spider)
Pili - appendage - Like bristle hair (like cilia) - Composed of protein pillin - Has point of attachments (to eachother or surfaces)
Sex pili - Allows transfer of genetic info between organisms (through asexual process)
Bacterial Growth Requirements (3) 1. Nurtients 2. Atmospheric 3. Temperature
Heterotrophs - Nutritional Requirement of Bacterial Growth - Uses carbon from ORGANIC COMPOUNDS 1. Photoheterotrophs - gets energy from sunlight 2. Chemoheterotrophs - gets energy & carbon from organic compounds
Autotrophs - Nutritional Requirement of Bacterial Growth - Uses carbon from atmospheric carbon dioxide 1. Photoautotrophs - gets energy from sunlight 2. Chemoautotrophs - gets energy from carbon compounds
What are the 6 Atmospheric requirements (for bacteria) 1. Obligate Aerobes 2. Obligate Anaerobes 3. Facultative Anaerobes 4. Aerotolerant Anaerobes 5. Microaerophiles 6. Capnophiles
Obligate Aerobes - atm requirements (for bacteria growth) - Grow only in the presence of oxygen - Aerobic cellular respiration
Obligate Anaerobes - atm requirements (for bacteria growth) - Doesn't rely on oxygen
Facultative Anaerobes - atm requirements (for bacteria growth) - Grows with or without oxygen - w/ oxygen = aerobic respiration - w/out oxygen = fermentation
Aerotolerant Anaerobes - atm requirements (for bacteria growth) - Can grow in the presence of oxygen, but cannot use it - Through fermentation
Microaerophiles - atm requirements (for bacteria growth) - Requires low concentration of oxygen (can't live in normal air)
Capnophiles - atm requirements (for bacteria growth) - Requires more carbon dioxide than in regular air - More acidic environment
What are the 4 Temperature Requirements (for bacteria growth) 1. Mesophiles 2. Thermophiles 3. Psychrophiles 4. Psychrotrophs
Mesophiles - temp requirement (for bacteria growth) - Moderate temp; 25 - 40 degrees celsius
Thermophiles - temp requirement (for bacteria growth) - Hotter temp; 45+
Psychrophiles - temp requirement (for bacteria growth) - Colder temp; 0 or lower
Psychrotophs - temp requirement (for bacteria growth) - Grows slowly at 0, but optimal growth at 25-30 - Food spoilage
Generation time - bacteria growth - Length of time required for binary fission to take place
4 Phases of Bacteria Growth 1. Lag Phase 2. Log/Exponential growth phase 3. Stationary Phase 4. Death Phase
Lag Phase - 1st phase; not a lot pf growth (before)
Log/Exponential growth phase - 2nd phase - rapid replication, ends due to lack of nutrients
Stationary Phase - 3rd phase - # of new organisms = #of dying organisms
Death Phase - 4th phase - bacteria lose ability to reproduce (even with good environment)
3 examples of Unusual Prokaryotes 1. Chlamydia 2. Rickettsiae 3. Mycoplasmas
Chlamydia - Gram-negative - Rod or coccus shaped; coccobacillus (kind of both) - Must have intracellular parasites (live inside host cell) - Cannot synthesize own ATP
What are the 2 'bodies' of the Chlamydia replication cycle 1. Elementary bodies (infectious form) 2. Reticulate bodies (growth form)
Replication Cycle (steps) of Chlamydia (6) 1. EB attaches to host cell 2. Host cell ingests EB, housing in an inclusion (sac) 3. EB reorganizes to form a reticulate body (RB) 4. RB divides, producing multiple RBs 5. Rbs convert back to EB 6. Eb released from host cell through lysis (bursting)
Rickettsiae - Small rods or coccobacilli - Contains RNA & DNA - Slime layer interferes with gram stain
Obligate Intracellular Parasite - Needs host cell
How do Ricketsiae reproduce? - Binary Fission - Transmitted by arthropod vectors (adding another organism to help them live)
Mycoplasmas - More in hospitals - Both DNA & RNA - No cell wall (pleomorphic) - Falculative Anaerobes (w/ or w/out oxygen) - Acid fast stain (since no cell wall)
Acid Fast Stain - Used for when no Cell Wall - Has ++mycolic acid (instead of PG) - Use red dye to stain (carbol fuchsin) - Acid-alcohol locks in colour (because of cell membrane lipids) - Other organisms colour blue/green
Archaea - Other Prokaryotes - More closely to Eukarya than Bacteria - Unique genetic sequences in rRNA - Can survive harsh conditions (adapts to heat, salt, acid pH, changes in pressure and atmosphere) - Hyperthermophiles (hot areas) - Methane produces-sulfur reducers
What are the 3 types of Eukaryote Cells? 1. Protists (protozoa) - Single-celled organisms lacking complex organization 2. Fungi (myceteae) - single or multi cellular; yeasts and mold 3. Plant and Animal
Eukaryotic Structures (9) 1. Glycolcalyx 2. Cell Membrane 3. Nucleus 4. Mitochondria 5. ER 6. Golgi 7. Vacuoles 8. Cytoskeleton 9. With or without Cell Wall
Locomotor Appendages - Only on some - External - Covered by extension of cell membrane - 9 pairs + 2 microtubular arrangment - Linked together by protein arms (pairs of circles on outside pic)
How do Flagellar locomotion move? 1. Whipping back and fourth 2. Twirling 3. Lashing out
Cilia - Function 1. Motility 2. Feeding 3. Filtering - in rows over surface; sway - help move things back and forth
Glycocalyx - Euk - Outermost (comes in contact with extracellular environment) - Network of polysaccharides fibres - Slime layer OR capsule
Glycocalyx - Functions (Euk) (3) 1. Protection to cell 2. Allows adherence/attachment to diff surfaces 3. Receive signals
Cell Wall (Euk) - Fungi & Algae - Provides structure and shape - Composed of Chitin (polysaccharide), glycoprotein, mixed glycans (molecules that can adhere to other molecules)
Cell Membrane (Euk) - Bilayer of phospolipids & sterole (heads out - H2O loving) - 2 proteins - 1. Peripheral 2. Integral - Provides stability to cells lacking a cell wall - Selectively permeable
Nucleus - Actually in eukaryotic cells (not in prokaryo) - rRNA synthesis - Surrounded by double membrane = nuclear envelope - Membrane contains pores which allows certain molecules to pas through
Chromatin - Dark granules (chromosomes) seen throughout the nucleus - In nucleus
Haploid - Single & unpaired nucleus
Diploid - Chromosome that are matched or paired
Mitosis - 5 stages 1. Prophase 2. Metaphase 3. Anaphase 4. Telophase 5. Cytokinesis
Prophase - Mitosis - Chromosomes become visible - Centrioles go towards opposite sides of cell - Spindle fibres form (from cytoskeleton) - Nuclear membrane disappears
Metaphase - Mitosis - Chromosomes line up on equator - Spindle fibres attach to centromeres of chromosomes
Anaphase - Mitosis - Centromeres split and sister chromatids separate and move to opposite poles
Telophase - Mitosis - New nuclear membrane forms - Nucleolus reappears - Furrowing of cell membrane
Cytokinesis - Mitosis - Cytoplasm divides to complete cell division
Interphase - Mitosis - Periods between mitotic divisions - Chromosomes less organized; appear as chromatin - Divided into 2 gap and synthesis phases
Rough ER - Transport materials from nucleus to cytoplasm - Protein are synthesized on ribosomes
Smooth ER - Involved in synthesis and storage of non-protein molecules (ie lipids, carbs)
Golgi Apparatus - Modifies, sorts, and packages proteins - Produces lysosomes and various secretory vesicles
Lysosomes - Vesicles; originate from Golgi - Contain enzymes (Peroxisomes - oxidative enzymes used to removes toxins) - Intracellular digestion of food particles - Protects agaisnt invading microorganisms - Removes cellular debris
Vacuoles - Membrane bound sac - Contains fluids or solid particles to be digested, excreted, or stored
Lysosomes + Vacuoles = ? Phagosomes - aids in digestions of nutrients to gain nutrients
Mitochondria - Powerhouse of cell - Makes ATP via electron transport chain - Divides independently through binary fission (without cell) - Contains its own strand of DNA
Structures of the Mitochondria 1. Smooth, continuous out membrane 2. Cristae - folded inner membrane; contains enzymes and electron carriers of aerobic respiration
Chloroplasts - In algae and plant cells - photoautotrophs (uses air to make carbon & sunlight for energy) - Oxygen produced as a by-product
2 Structures of the Chloroplast 1. 2 membranes - Smooth outer membrane - Folded inner membrane - thylakoids 2. Stroma matrix around thylakoids - Has its own genetic info, can divide without cell cycle
Cytoskeleton - Helps provide support - Flexible framework of molecules
6 Functions of the Cytoskeleton 1. Anchors organelles 2. Provides support 3. Produces movement of cytoplasm 4. Important role in intracellular transport 5. Forms spindle fibres 6. Movement of the cell as a unit
Ribosomes - Site of protein synthesis - Scattered freely in cytoplasm or with RER - Similar structure to prokayotic ribosomes but larger
Fungi - Includes mold, mushrooms, and yeasts - Heterotrophs - from organic compound - Scavengers
Fungi - Structure - Unicellular or multicellular - Cell walls contain chitin (instead of PG) - Can join together - colonies
Fungi - Reproduction - Sexually or asexually - Spore formation (sexually) OR budding (asexually)
Fungi - environmentally (what are they and how do they get their nutrients) - Live as saphrophytes/saprobes (scavengers/decomposers) - Nutrients through absorption - organic compounds
Human Fungal Pathogens (3 Classifications) 1. Yeast - in body; like warmth 2. Mold - environmentally; like cold 3. Dimorphic fungi - very adaptable
Yeasts (reproduction? cellular?) - Unicellular microorganisms - Asexual (budding - similar to binary fission) - Best in moist environment
Molds - Multicellular microorganisms - Asexual - Develop characteristic hyphae - Hyphae grow to form a mycelium (e.g. white mold on tomatoe)
Hyphae 1. Septate - divided/separate into distinct cell-like units 2. Coenocytic - no septal divisions
Asexual Reproduction - fungi - similar to binary fission (for yeast) - molds reproduce by fragmentation (little pieces break off) of their hyphae and by spore formation
Asexual Spore Formation (2 types) 1. Sporangiospores - form inside a sac (sporangium); spores released when sporangium ruptures 2. Conidia - produced at tips/sides of hyphae; pinch/break off and then travel
Sexual Reproduction - fungi - When nutrients are limited - Can be dispersed/travel widely throughout environment by air, H2O, and other organisms - Germinates when good conditions
+mycelium and -mycelium =? (sexual reproduction) = dikaryon; then divides by meiosis to end up with variations
What do the 2 forms of Dimorphic Fungi depend on? - Grows in 2 forms; depends on the temperature
2 Forms of Dimorphic Fungi 1. Mold with septate hyphae @ 25 degree celsius (low) 2. Yeast in tissues @ 37 degree celsius (high)
Systemic Mycoses - Infection through blood stream
Fungal Growth Requirements - Heterotrophs - mostly saprobes/saprophytes (scavengers/decomposers) - Can be parasitic (needs host cell) - Aerobic - Some yeasts are facultative anaerobic (w/ or w/out oxygen)
4 Different types of fungal infection diseases 1. Superficial mycoses 2. Lutaneous mycoses 3. Subcutaneous mycoses 4. Systemic infections (inhaling then goes through bloodstream)
Superficial Mycoses - Tineas = infection of epidermis - Waits for a weakened immune host - Usually direct contact (e.g. attacks melanocytes/pigments)
Cutaneous Mycoses - Infections extend deeper into epidermis - Involves stratum corneum and occasionally upper dermis
Subcutaneous Mycoses - Occurs after a puncture (poked with something that has fungus on it) - Fungus invades the deeper layers of the dermis
Systemic Mycoses - Fungal infection which spreads throughout the body - Portal = respiration then bloodstream
Mycotoxins - Chemical by-products from fungal metabolism - Ingesting contaminated food
Long term ingestion of Mycotoxins can cause 3 things 1. Liver & Kidney damage 2. Gastrointestinal or gynecological disturbances 3. Cancer
Protozoa - Kingdom Protists - Unicellular or colonial organisms - Contains major eukaryotic organelles (EXCEPT chloroplasts)
Structural Features of Protozoa - Cytoplasm into 2 layers 1. Ectoplasm (clear outer layer involved in locomotion, feeding, and protection) 2. Endoplasm (granular inner layer w/ nucleus. mitochondria, and vacuoles) - No cell wall; but has cell membrane
Locomoter Appendages in Protozoa (3) 1. Flagella 2. Cilia 3. Pseudopods - cytoplasm flows into 'fake feet' = migrates into diff directions
Nutrition of Protozoa (how do they get their carbon, what do they need, etc) - Heterotrophic Organisms - Uses live cells of bacteria and algae - Scavengers - Some parasitic - Trophozoite stage = active feeding stage - no vegetative stage
Habitat of Protozoa - In fresh and marine water, soil, plants, and animals - Converts to a resistant dormant stage when feeding/growth are harsh (go out into cyst until environment is better)
Virion - Fully formed virus that's able to now establish infections in a host cell
Basic Structure of a Virus - Capsid (protein coat) - Nucleic acid - DNA or RNA (single or double)
How do Viruses multiply? (general) - By taking over a host's cells genetic material (since they're not living organelles)
Capsid (protein shell) + nucleic acid (genetic info) = ? - Nucleocapsid
Do viruses always have an envelope? - Not always
What are CAPSIDs made out of? - Proteins called capsomeres
What are the 2 capsomere arrangements? 1. Helical - like a tin can looking 2. Icosahedron - Diamond/spider looking one
How are the Icosahedron Capsules formed? - 12 spaced corners - 20 triangular faces - 30 edges
How is the viral envelope formed? - By budding through a host membrane
What's on the outside of a viral envelope? - Glycoproteins
What do the spikes do on a virus? - Viral attachment to host cell (remember it has lock and key)
What does the viral envelope do? - Attacks - Protects nucleic acid from enzymes and chemicals outside of host cell - Infects viral DNA/RNA into host cell - Can also stimulate the immune system to produce antibodies that protect the host cell agaisnt future infections
What are the 2 atypical/complex viruses? 1. Poxviruses 2. Bacteriophages
What are proxviruses? And its 3 features? (Think of hamburger shaped) - Large DNA viruses that lack a capsid 1. Nucleoid - central disk structure, sorrounded by membrane and 2 lateral bodies 2. Lateral bodies - contains enzymes for viral replication (penetration) 3. Lipoproteins & Coarse fibrils - densed layer
What are Bacteriophages? - Viruses that only infect bacterial cells (what allows bacterial cells for getting drug resistance - bc they pick up virus DNA)
What are the 2 structures of a Bacteriophages? 1. Icosahedral Head - contains nucleic acid 2. Tail - Has attached fibres, sometimes surrounded by sheaths (for protection)
Genome - Part of Nucleic Acid - Is sum of all genetic info (DNA/RNA - single or double) - Carried by nucleic acid
Viral Enzyme Functions (3) 1. Polymerases - form large polymers (DNA or RNA) - attachment 2. Replicases - copy DNA 3. Reverse Transcriptase - allows the synthesis of DNA from RNA ase - enzyme
6 Animal Virus Life Cycle 1. Adsorption 2. Penetration 3. Uncoating 4. Replication 5. Assembly 6. Release
Adsorption (1st step) - Cell membrane receptors specific to viral configurations (lock & key) - Host Range - limits virus of being able to cross over sometimes (from characteristics of cell)
Penetration (2nd step) - Direct fusion of virus with host cell membrane (nucleocapsid released into cell's interior)
Uncoating (3rd step) - Endocytosis - cell membrane engulfs liquid or solid material into a vacuole - Vacuole enzymes dissolve viral envelope and capsid uncoating nucleic acid (Into vacuole - then enzymes uncoat it)
Replication (4th step) - Viral nucleic acids take over host cell's synthetic and metabolic machinery
Assembly (5th step) - Nucleic acid strand inserted into empty capsid shell = nucleocapsid formation - Viral spikes added on when leaving/budding off
Release (6th step) - Lyses = non-enveloped - Budding/exocytosis = get envelope from membrane when leaving
Replication/Multiplication of Bacteriophages - Similiar to animal viruses but no uncoating phase; instead injected in (since its like a spider thingy)
Retrovirus - What do they do? - Uses RNA as a template to produce viral DNA (as a template) - Has 2 copies of ssRNA & reverse transcriptase
Retrovirus Multiplication Cycle (4) 1. Retrovirus penetrates host cell 2. After uncoating reverse transcription of the viral RNA produces dsDNA 3. New viral DNA is transported into host cell nucleus; integrated as provirus & then replicate 4. Mature retrovirus leaves, acquires envelope
What is a Morphological (Cytopathic) effect? - Changes in the shape of a host cell caused by a viral infection
What are the 6 Morphological (Cytopathic) effects? 1. Altered Shape 2. Detachment from tissue surface 3. Lysis 4. Membrane Fusion 5. Altered membrane permeability 6. Apoptosis (programmed cell death?)
What is a inclusion body? - Compacted masses/debris of viruses or damaged cell organelles (DNA - nucleus; RNA - cytoplasm)
What are the 3 Host Cell's Damages? 1. Physiological Effect 2. Biochemical Effect 3. Genotoxic Effect
What is the Physiological Effect? - Addition of viral proteins into plasma membrane; changes of characteristics and/or functions leading to altered cellular activities
What is the Biochemical Effect? - Inhibition or alteration of host cell's macromolecules (e.g. lipids, fats, carbs)
What is the Genotoxic Effect? - Affects future generation - Genotoxic substances can damage host cell DNA - Teratogenic Effect - mutation - Potential start of cancer
What are the 5 Viral Infections? 1. Abortive Infections 2. Lytic (cytocidal) Infection 3. Persistant Infections 4. Slow Infections 5. Transforming Infections
What is the Abortive Infection? - When the virus can latch on, but cannot proceed further because the host cell is non-permissive (cannot reproduce)
What is the Lytic (Cytocidal) Infection? - Infection of permissive cells which kill the host - Allows virus to hijack metabolic machinery
What are the 2 Persistant Infections? 1. Chronic- productive but not lytic 2. Latent - has a dorment stage/ like chicken pox and turburculosis)
What is a Slow Infection? - Prolonged incubation period
What is the Transforming Infection? - Alters cell properties
What is a Oncogenic Transformation? - Genetic modification of cell proliferation control - tumour cells
Created by: alexmanikus