-
Algae:
- Photosynthetic
- Some are unicellular
- Mostly aquatic with chloroplasts and cholorophyll
ex: spirogyra, diatoms, chlamydomonas
-
Protozoa
"Animal Like"
Ways to move: cillia (paramecium), flagella (euglena), pseudopods (amoeba) and Phylum Apicomplexa
-
Cyanobacteria:
- Photosynthetic prokaryotes
- No chloroplasts
- Produce Oxygen (O2)
ex: anabaena
-
Anabaena (Pond Organism)
- A gliding cyanobacteria (belongs to domain Bacteria)
- Heterocyst: fixes nitrogen: take Nitrogen gas from air
- They have photosynthetic pigments: give off a blue-green hue.
- Trichromes: found in chains, No chloroplasts, Produce Oxygen and Use Nitrogen Gas.

-
Spyrogyra (Pond Org)
- Part of Algae group: contain distinctive spiral chloroplasts.

-
Diatoms (Pond Org)
- Photosyn unicellular Prokaryotes:belong to ALGAE group.
- Either centric or pennate (billaterally symetrical and elongated)
- Pigment: fucoxanthin--gives off a golden brown hue.

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Giardia Lambia Cysts:
--> what is a cyst?!
--> where is it found, how is it transmitted?
cyst: inactive form, non-motile and resists DISINFECTION.
-oval shape, 4 nuclei
Shed in Feces, transmitted in fecally contaminated water and by oral contact of food.
-
Giardia Trophozoite:
--> what is a Trophozoite?
--> common where?
--> features?
- Trophozoite: Active-Feeding form
- Most common in duodenum; also found in stool
- Has two nuclei with karyosomes and axostyle-a line in the middle of the cell and 8 flagella
-

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Plasmodium Falciparium (ring stage)
- Transmitted by mosquitos;
- cause malaria: fatal vessel obstruction and thrombosis.
- --sporozoite transmitted my mosquito bite
- --reproduces in liver THEN RBC's
- Ring stage-parasite in RBC.

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Trichomonas Vaginalis
Most found in vaginal area, transmitted sexually- STD: trichomoniasis
-
What are the groups of microbe organisms:
- Bacteria
- Fungi (yeasts/molds)
- Protozoa
- Algaea
- Viruses
- Helminths
-
Bacteria (group)
--> pro/eukaryotes?
--> Shapes?
--> cell walls?
--> Reproduction?
--> how do they eat?
- Unicellular prokaryotes (means DNA is NOT in a nuclear membrane)
- Either Baccillus (rodlike), coccus (sphere), spiral (corkscrewed)
- Cell walls: Peptidoglycan (carb + prootein complex)
- Reproduce by binary fission-divide into two equal cells
- Some can photosynthesize, while others get food inorganically.
-
Archaea (group)
-->pro/eukaryotic?
--peptidoglycan?
--> what are three groups?
--> pathogenic?
- Prokaryotic-No peptidoglycan
- 3 groups: methanogens, extreme halophilles (salt lovers) and extreme thermophiles (hotsprings)
- **NOT pathogenic
-
Fungi (group)
--> pro/euk?
--> cell walls?
--> uni/multi cell?
--> 2 types and characteristics?
- Eukayotes
- Uni or multicellular
- cell walls: chitin
- yeast: unicellullar
- mold: reproduce either sexually or asexually
-
Protozoa:
--> Pro/euk?
--> uni/multi cell?
--> how do they move?
--> how do they survive?
- Unicelluar
- Eukaryotic
- Move with: flagella, pseudopods, cillia
- environments: free living or parasitic
- Some can photosynthesize (euglena)
-
Algae:
--> pro/euk?
-->Uni/multi cell
--> cell wall:
--> most common where?
--> how do they help envir?
--examples
- Photosyn. Eukaryotes
- usually unicelluar
- cell wall: cellulose (carb)
- Most found: in fresh water, salt water, and soil
ex: spyrogyra, diatoms,
**Produce O2 and carbs for other organisms.
-
Viruses:
--> Nucleus memb?
--> euk/pro?
--> where do they reproduce?
- Accellular o.0
- Either only have DNA or RNA in a lipid membrane (neither euk/pro)
- Reproduce in hosts
-
Helminths:
multicellular animal parasites
Includes: flat and round worms
-
Three Domains & 4 kingdoms:
- Bacteria
- Archaea
- Eukarya
- 1.Animalia-Helminths
- 2. Protista: protozoa & algae
- 3. Fungi
- 4. Plants (no microbes)
-
Gram Stains
Most useful-classifies bacteria into two large groups-gram positive and gram negative.
- Procedure:
- 1. heat-fixed smear covered with crystal violet( Primary stain: gives its color to all cells).
- 2.Then dye is washed off, smear covered with iodiine and washed off so that both gram positive and negative bacteria appear dark violet.
- 3. Slide is washed with alcohol solution: decolorizing agent-removes purple from cells of certain species.
- 4. Alcohol is rinsed off ==> slide is stained with safranin (basic red dye). Blot dried.
-
Gram Positive:
Bacteria that retain the dye after decolorizing alcohol
-->thicker peptidoglycan cell wall,dye and iodine enter and form CV-I complex-larger molecule than crystal violet molecules that entered, so it cannot leave==> so alcohol does not wash out the dye.
-
Gram Negative:
Bacteria that LOSE the dark violet color after decolorization
( safranin must be added to stain these pink to counter the original purple stain so called a "counterstain")
- --> contain layer of lipopolysaccharide as part of cell wall (alcohol wash disrupts this outer layer, and the "CV-I" complex is washed out through the thin layer of petidoglycan)
- -->must be redyed with safranin. :)
-
Psychrophile
- Likes 0-20 deg C
- 15= optimum
- -cold-loving microbes
- -found in oceans/polar regions.
- -unlikely to spoil food
-
Psychrotroph
Grow slowly at low temps but optimum from 20-30
-Responsible for food spoilage; grow well at refrigerator temps though cold temps slow down reproductive rates.
-
Mesophile
Optimum: 20-40 deg temps "middle" (room)
- -moderate-temperature loving microbes
- -live in terrestrial/aquatic areas, plants & animals
- - may cause disease: likes body temp of host
-
Thermophile
Optimum: 40 degs Celsius and higher
- - heat-loving microbes
- -endospores: fromed by these bacteria; may survive heat treatments given to canned foods.
- -found: hot spring run offs; compost piles
- ex: Thermus aquaticus: yellowstone
-
Hyperthermophile
Extrememophiles!
- Optimum: Higher than 80 deg C (boiling/acidic water)
- Domain: Archaea; different from bacteria (don't denature)
ex: Sulfolobus (yellowstone)
-
Biofilms
-quorum sensing
-form where?
-preventions?
microbe communities; in slime (matrix of polysaccharides with DNA/proteins)
- -quorum sensing: allows bacteria to coordinate activity and group together
- ex: plaque, pond rocks
- -work cooperatively on same task
- -primitive circulatory systems: incoming nutrients and waste channels
- -1000x More resistant to microbicides; form on medical devices
- -protected by antibodies, WBC phagocytosis and antibiotics
Preventions: block quorum sensing, incorporate antimicrobial into possible biofilm surfaces; must physically remove them
-
Thioglycollate medium
- Reacts with oxygen, removed oxygen from medium
- --> good for growing bacteria
-
Two reasons to use agar?
can liquify at 100 deg celsius, 50 degrees water bath keeps it liquid and does not injure bacteria when doing pourplates. --Incubated at 100 deg friendly to thermophilic bacteria
-
Binary Fission Diagram
Shows binary fission (bacteria) or mitosis (fungi) reproduction
- a. Lag Phase: Preping/intense activity; no increase
- b. Log Phase: exponential increase
- c. Stationary Phase: equilibrium (deaths balance new cell production)
- d. Death phase: decreasing population
-
What is the equation for calculating number of bacteria?
N=N0 (2n)
- N: total number of bacteria
- N0: number of cells at beginning/start
- n: number of generations
-
Direct Methods to count bacteria and their advantages/disadvantages:
- 1. Direct microscopic count:
- --> Advantage: fast;
- --> Disadv: count dead and viable (still reproducing/alive) cells
- 2. Standard Plate count:
- --> Adv: Only counts viable cells.
- --> Disadv: slow because you have to wait days
-
Indirect methods of counting bacteria: Two ways
ONE WAY: Turbidity: Gets the relative number of all cells; complements standard plate count ("how cloudy")
- 1. Use spectrophotometer
- 2. Measure light absorbance of test tube with bacteria;
- 3. measurements are in Optical density (stay between 0 to 2)
**CORRELATES WITH STANDARD PLATE COUNT BECAUSE IT MEASURES DEAD CELLS ALSO*
- SECOND WAY: Dry weight or mass
- --> Advantages: Fast and good for clumping organisms
- --> Disadvantages: measures live and dead cells
-
Prokaryotes: distinguishing characteristics
- 1. Dna has no enclosed membrane
- 2. lack membrane enclosed organelles
- 3. cell walls are complex polysacharide peptidoglycan
- 4. Divide with binary fission
-
Eukaryotes
- 1.Has nucleus to sep dna from cytoplasm
- 2. have many membrane enclosed organeles
- 3. chemically simple cell walls.
- 4. cell division: mitosis.
-
Plasma Membranes: Prokaryote vs. Eukaryote
BOTH have it!
similarities: phospholipid bilayer with proteins, separates cells from outside
Differences: not applicable
-
Cell Wall: Prokaryote vs. Eukaryote
- Prokaryote:
- Bacteria has peptidoglycan;
- Archea-Pseudopeptidoglycan
- Eukayotes:
- Fungi: Chitin
- Plants&Algae: Cellulose
Similarities: structural support, resists bursting, made of polysaccharides
Differences: Chemical composition; some eukaryote do lack cell walls
-
Chromosome (genetic material)
Prokaryotes: Circular, only one chromosome in "nucleoid" region
Eukaryotes: Linear, variable number of chromosomes/associated with histone protiens
- Similarities: Made of DNA
- Differences: Different (?) and organization
-
Nucleus: Prokaryote vs. Eukaryote
- Prokaryote: NONE
- Eukaryote: Present :D
**THIS IS THE DIFFERENCE**
-
Flagellum: Prokaryote vs. Eukaryote
Prokaryote: Rotational motion in Bacteria
Eukaryote: whiplike in animals
- Similarities: Locomotion
- Differences: Diff type of motion & chem compositon
-
Ribosomes: Prokaryote vs. Eukaryote
- Prokaryote: Present
- Eukaryote: Present, some associated with RER
- Similarities: Protein synthesis
- Diffs: prok have smaller ribosomes
-
Membrane Bound Organelles: Prokaryote vs. Eukaryote
- Prokaryote: NOT PRESENT,
- Eukaryote: Rough ER, Mitochondria, Golgi Body, lysosomes, chloroplast
- Similarities:None.
- Differences: Prok lack; euk often have several membrane bound organelles
-
Capsule (pg 70)
- Firmly attached to cell wall (made of glycolax-gelatinous polymer)
- -protect pathogenic bacteria from phagocytosis :(
-
Slime Layer
- another type of glycolax;
- Loose, thinner, flexible attached to cell
- -Helps bacteria attach to surface
-
Endospores (70. 95-97)
-purpose and characteristics
-endospore components
-locations
-example:
Resting structures formed by some bacteria, allows for survival during adverse environmental conditions (dry conditions)
- Characteristics:
- very little water
- resistant to heat, uv rays and disinfectants
- Components: cytoplasm, plasma membrane, ribosomes, peptidoglycan, spore coat (protein) and dipicolinic acid
Locations: terminal(very end), central and subterminal (almost end)
ex: clostridium tetani
-
Sporulation:
(germination?)
- 1. DNA is replicated
- 2. Endospore forms when plasma membrane, peptidoglycan layer, and spore coat surround DNA
- 3. endopsore is related as vegative cell disintegrates
"germination": return of endospore to it's vegetative state
-
Lysosomes:
form by golgi complexes; store digestive enzymes
-
EPS: extracellular polymeric substance
a glycocalyx that helps cells in biofilm attach to target environment and allow bacteria to survive
-
Peptidoglycan:
polymer consisting of NAG (N-acetylglucosamine) & NAM (N-acetylmuramic acid) and short amino acid chains; penicillin interferes with this wall
--in gram positive cell walls; crystal violet combines with peptidoglycan but decolorizer removed the lipid outer memb of gram negative bacteria and washes out crystal violet.
Gram neg walls: thin peptidoglycan layer and a lipopolysaccharide-lipoprotien-phospholipid layer (-.-)
-
Gram Negative cells (chemical structure)
- -MUCH more complex-Thin layer of peptidoglycan
- -LPS (lipopolysaccaride)
- -Porins
-Periplasms with chemoreceptors: gel like fluid between outer membrane and the plasma membrane - -NO teichoic acids;
- OUTER membrane: contains LPS, lipoprotiens and phospholipids
- --gives wall strong neg charge
- --provides barrier to antibiotics, digestive enzymes,and dyes
- --Porins: channels allow nucleotides, amino acids
-
Gram Positive Cells (chemical structure)
- -Many layers of peptidoglycan
- -Thick ridgid structure
- -teichoic acids: alcohols (glycerol) and phosphate; gives wall antigenic specificity to allow group into "gram pos" cells
-
How do Gram stains work?
-Crystal violet purpose
-Iodine purpose
-Alcohol effect to both walls
- ADD what dye after, what kind of dye is this?
-Based on differences between cell wall structure (type of differential stain)
Crystal violet (primary) stain both cells
Iodine: forms large crystals with dye that are TOO large to escape through wall
Alcohol: dehydrates peptidoglycan of gram positive cells and make it more impermeable to crytal violet-iodine. BUT on gram negative: the alcohol dissolves the outer membrane of gram negative cells and even leaves small holes in the thin peptidoglycan layer SO THAT crystal-violet-iodiine leaves!
This is why safranin must be added to stain gram negative cells (turn them red)--contrasting stain
-
Bacterial shapes:
coccus, spiral, star, pleiomorphic
- Rod/bacillus: cylinders
- coccus: sphere
- spiral: spirillium (w/flagella) or spirochete (axial filaments-rotate)
- star
- pleiomorphic: many shapes (corynebacterium diphtheriae-cause diphtheria)
- coccobacilillus
-
Bacterial Cell ARRANGEMENTS:
strepto
tetrad
staphylo
palisade
diplococcus
- the ways cell stick together:
- 1. strepto: chains of cells
- 2. tetrad: group of 4 cells
- 3. stahylo: grape like clusters
- 4. palisade: picket fence
- 5. diplococcus: two circle oo
-
Cytoplasmic bodies
Nutrient storage
metachromatic granules
magnetosomes
- a. nutrient storage:
- --> ex: polysaccharides granules for store starch
- --> lipid inclusions store lipids
- -->sulfur bacteria store sulfur as energy source
- b. metachromatic granules with phosphate (turn red): inorganic phosphate storage
- --> used to diagnose Corynebacterium diphtheriae
c. magnetosomes: contains iron compounds, use to orignet to magnetic fields
-
Biofilms
-Community of bacteria; form at liquid-solid interfaces; slime layer ( extracellular polymeric substance-EPS:helps bacteria attach to surfaces)
-
-protected from antibodies and antibiotics; wbc's create inflammation
-
-found: teeth, rock in a pond, pet's waterdish
-
advantages of biofilm:
- prevents dehydration
- share nutrients
- protection from host immune system (antibodies or wbc phagocytosis)
-
Compound:
pure substance that can be broken down into simpler substances (elements)
-two ore more elements joined together
-
Molecule
Two or more atoms joined together
-
Four groups of biological molecules?
- 1. carbs
- 2. Lipids
- 3. Proteins
- 4. Nucleic acids
-
Carbohydrates
Functions: energy source/storage, carbon source and part of cell structure
- -Composed of C,H,O
- -Hydrophillic (waterloving)
-Sacchardies
- Monosaccharides: hexose, pentose
- Disaccharides: lactose (glucose+galactose) and sucrose/canesugar (glucose and fructose)
- Polysaccharides: cellulose (plant/algae cell walls), starch (energy storage), petidoglycan (bacterial cell walls)
-
Lipids functions and structure::
1. triglycerides
2. fatty acids
3. saturated vs. unsaturated
4. phosoplipids
5. sterols
Fn: energy storage, cell memb components
Structure: C,O,H and sometimes P & S
-HydroPHOBIC (dont dissolve)
Triglycerides: 3 carbon glycerol + 3 Hydroxyl (OH) groups
Fatty acids: C-H chain + carboxyl group at the end
saturated fatty acids: only single bonds b/w carbons (fats: butter and shortening)
Unsaturated: double or triple bonds give it a kink (oils)
Phosoplipids: two fatty acids + glycerol + phosphate group + "R" group (hydrophillic)
Sterols: 4 connected carbon rings, not composed of fatty acids, hydrophoics
-
PROTIENS
FN: cell structure (flagella, cytoskeleton, enzymes, chem signals)
exotoxins: transporters in cell membranes (botulism toxin)
- Amino acid: building block of proteins:
- --> amino group (NH2)
- --> carboxyl group (COOH)
- --> R group connected to central carbon
Peptide bonds: created by dehydration synt. b/w 2 amino acides; spacial type of covalent bond
Peptide: short chain of amino acids; Polypeptides (structure: primary, secondary, tertiary and quaternary sturcture)
-
Nucleic Acids:
DNA: genetic code/template fro protein making
RNA: helps make proteins
- Nucleodtide has 3 parts:
- 1. 5C sugar (ribose/deoxyribose)
- 2. Phosphate backbone(PO42-)
- 3. Nitrogenous base (can form H bonds)
- DNA bases: Adenine, guanine, cytosine, and thymine
- RNA bases: uracil instead of thyamine
ATP (adenosine triphosphate): function as energy "currency"; stores and provides chemical energy, made out of ribose, adenine and 3 phosphates linked together.
-
Diphtheria Symptoms:
Begins with sore throat and fever, neck swells
- -often affects throat(pharynx) and larynx (voicebox)
- -creates a pseudomembrane of fibrin, dead tissue and bacterial cells that clogs throat/air passage
-
Diphtheria Microbe:
- Microbe: Corynbacterum diphteriae
- --> gram positive
- --> non-endospore-forming rod
- --> cell arranged: palisades
-
Diphtheria Diagnostic methods & treatments
Diagnose: throat swab culture; PCR (polymerase chain reaction-method to make many DNA copies) to grown and study
treatments: Antibiotics & antitoxins (penicillin/erythromycin)
-
Pertussis:
Whooping cough; damages cilliated cells in respiratory system
- -paralyzes the cilliated cells
- -cause inflammation
- -impairs immune response
-
Pertussis Microbe
- caused by Bacterium "Bordetella pertussis"' obligatory aerobic
- gram negative
- coccobacillus
-
The stages of Pertussis:
First Stage (catarrhal stage) resembles common cold- coughing, sneezing, low fever (100 deg F)
Second Stage (Paroxysmal stage): severe prolonged coughing fits, may make "whoop" sounds; difficult to cough up phlegm when cilliated cells are destroyed.
Third stage: coughing eventually become less frequent and less severe (convalescence)
-
Pertussis Treatments:
-Herd immunity
- 1. First stage: give antibiotics
- 2. second stage:
- 3. DTaP: subunit of pertussis (begins at 2 months old, given 3 shots total)
- 4. Boosters for teens
- 5. Tdap: adults
- 5. Vaccine rate: 93% herd immunity (reduced chance of infection of vulnerable individuals if a certain high percentage of individuals in the populations are vaccinated or immune.)
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