Module 3 test for microbiology Flashcards
Bacteria growth curve
Lag (adjust to new environment), Log (Binary phase, exponential phase), stationary (birthed bacteria vs death= equal, Stains gram variable, and spores are produced), and death ( death are greater than birth)
Binary Fission
Binary Fission:
1. Simple asexual reproduction in single-celled organisms like bacteria.
2. Begins with genetic material duplication.
3. Cell elongates.
4. Division into two through constriction at the center.
5. Produces two identical daughter cells with copied genetic material.
6. Enables quick and efficient reproduction.
Conjugation 4 step process
1) Donor cell attaches to a recipient cell with its pilus, the pilus draws the cell together.
2) the cell contacts one another
3) one strand of plasmid DNA transfers to the recipient
4) the recipient synthesizes a complementary strand to become F+ cell; the donor synthesizes a complementary strand, restoring its complete plasmid.
Transduction
-Accidentally moved between each other through a virus as a vector (bacteriophage).
1) Bacteriophage attaches to bacteria
cell
2) Disperses genetic material into
bacteria cell.
3) Bacteriophage uses host cell as a
vessel for reproduction; kills bacteria
cell and releases viral cells
4) New virus attaches to a new bacteria
cell
5) Disperses foreign genetic material,
from former bacteria cell, into new
bacteria cell
6) Genetic material fuses with
chromosome in cell
Transformation
Sexual reproduction through free floating DNA which is taken to incorporate there own.
What is an oxidation reaction and what is always accompanied with?
It is the loss of electrons, hydrogen atoms, or the gain of oxygen.
whenever there is oxidation the opposite reaction (reduction) also occurs
Bacterial growth problem example…
1) # gen growth= minutes given/ bacteria generation time in minutes
2) if two growths, growth 1= cells 2, growth 2= growth 1 cells2
3) if cells per mL= Cells/ mL
Define a chemoheterotroph and provide at these 3 examples?
They obtain their energy from the decomposition of plants and animals in the ecosystem.
examples, bacteria, fungi, and protozoa.
what is so special about chemoheterotrophs?
They derive their energy via chemical reaction (Chemo) of organic compounds.
How do photoheterotrophs obtain their energy?
They obtain energy via light (chlorophyll- like pigments)
What do autotrophs use as their energy source?
They use CO2 as a source of carbon.
What are chemoautotrophs?
They catabolize (Oxidize) organic compounds such as carbohydrates, lipids (fats), proteins etc… these microbes include most bacteria, fungi, and protozoa
What are photoautotrophs?
Purple and green bacteria, algae, and the cyanobacteria. these phototrophic microbes either have chloroplasts with chlorophyll (algae) or chlorophyll- like pigments (bacteria)
What are the two oxidative process which provide energy?
Respiration and fermentation. they both provide energy.
Respiration components?
-Aerobic respiration: The final hydrogen and electron acceptor is molecular oxygen, which requires Oxygen.
-Anaerobic respiration: inorganic compounds other than molecular oxygen serves as the hydrogen or electron acceptor, lack oxygen.
Fermentation components?
organic compounds serve as both hydrogen acceptor under anaerobic conditions.
review microbial metabolism diagram
:)
Review bacterial metabolism (packman) diagram
:)
Extracellular (region, function, and process)
Region- Outside the cell.
Function-Involved in catabolism (digestion) of macromolecules so they may enter the cell.
Process- Most are hydrolytic enzymes that hydrolyze molecules by introduction of water.
Examples of extracellular enzymes (enzyme, hydrolysis of…) 5 types
1) Proteinase- H of proteins, proteases, peptones, and peptides.
2) Gelatinase- H of gelatin and destruction of ability to “gel”.
3) Amylase (stress-induced)- H of starch converted to maltose.
4) Lactase- Lactose to glucose and galactose.
5) Sucrase- Sucrose to glucose, fructose
Intracellular (region, Function, and process)
Region- Inside the cell
Function- Involved in catabolic and anabolic reactions.
Process- Classifies according to the type of reaction of process.
Examples of Intracellular enzymes ( Enzymes, and reaction. 7 types
1) Permease- Transport of nutrients.
2) Hydrolase (water)- Catalyze splitting of chemical bonds into H2O.
3) Transferase- Transfer chem group molecule to molecule.
4) oxido- reductase- Catalyze loss/ gain electrons increase energy
5) Lyase- Removes chemical groups from molecules without H2O.
6) Isomerase- Re-arrangement of atoms within a molecule.
7) Ligase- Catalyze the joining of two molecules
Carbon and energy requirements (1Chemoautotrophs, 2Photoautotrophs, 3Photoheterotrophs, and 4Chemoheterotrophs)
- CO2, Chemical reaction of inorganic
- CO2, Radiant E (light) photosynthesis
- Organic Compounds, Radiant E (light) photosynthesis
- Organic Substrates, Chemical reaction of organics
Nutritional requirements of chemoheterotrophs. 7 type ( Example and function)
1) Nitrogen- ex: Nitrates, Function: Produce cellular protein and nucleic acids.
2) Carbon- ex: Carbohydrate, Function: Backbone for all cellular components.
3) Sulfur- ex: Sulfur-containing amino acids, Function: Produce all proteins and cellular components.
4) Phosphorus- ex: inorganic phosphates, Function: Synthesize phospholipids, nucleic acids, and nucleotides.
5) Trace elements- ex: Cobalt, manganese, iron, Function: Produces B12
6) Vitamins- ex: B12, k, choline , Function: Used in coenzyme production.
7) Water ex: H2O , Function: Nutrients in, waste out.
Oxygen requirements of the 6 environmental; factors.(1) Obligate Aerobe, 2) Obligate Anaerobe, 3) Facultative Anaerobe, 4) Microaerophiles, 5) Aerotolerants, 6) Capnophile)
1) Obligate Aerobe- oxygen must be present for growth
2) Obligate Anaerobe- oxygen cannot be present for growth, lacks enzymes to tolerate oxygen
3) Facultative Anaerobe-grows with or without oxygen, best with oxygen
4) Microaerophiles – grows only when there are reduced amounts of oxygen
5) Aerotolerants- ignore oxygen
6) Capnophile –grows only in carbon dioxide rich environments
PH Classification:
1) Acidophile
2) Neutrophile
3) Alkaliphile
1)Acidophiles:
- Bacteria that thrive in acidic conditions, with a pH < 4.
- Example: Thiobacillus thiooxidans, which grows best at pH 1.
- Often found in mining effluents enriched with metal sulphide ores.
- Derives energy from the oxidation of sulfide, producing H2SO4.
2)Neutrophiles:
- Grow at or near a neutral pH (7).
- The majority of bacteria fall into this category.
- Optimal growth range: pH 5.5 – 8.0.
3)Alkaliphiles:
- Bacteria that grow in alkaline conditions, with pH > 10, in the range of 8.5 – 11.5.
- Examples include many Bacillus species.
- Vibrio cholera, the cause of cholera, can thrive at a pH as high as 9.0.
- Alcaligenes faecalis, involved in UTI infections, degrades urea to produce ammonia, increasing pH.
- Both can thrive at pH 9 and tolerate a pH of 10.
Temperature classification:
1) Psychrophiles
2) Mesophiles
3) Thermophiles
4) Hyperthermophiles
- Psychrophiles:
- Prefer cold temperatures (-5°C to 15°C).
- Found in chilly environments like arctic soils, glaciers, and polar regions.
- Example: Leifsonia aurea survives at -22°C in Antarctic ponds.
- Mesophiles:
- Thrive in moderate temperatures (25°C to 45°C).
- Common in everyday environments like soil and the human body.
- Pathogens like Escherichia coli grow within this range.
- Thermophiles:
- Excel in high temperatures (>45°C to 70°C).
- Occur in warm places like compost piles and soils undergoing fermentation.
- Example: Thermus thermophilus thrives at 65°C in Japanese thermal vents.
- Hyperthermophiles:
- Demand extremely high temperatures (>75°C).
- Often Archaea found in volcanic-heated environments surpassing 100°C.
- Discovered in ocean floor thermal vents and Yellowstone hot springs.
- Example: Aquifex aeolicus grows at 85°C to 95°C.
Gaseous classification:
1) Obligate Aerobes
2) Obligate Anaerobes
3) Facultative Anaerobes
- Obligate Aerobes:
- Require oxygen for growth.
- Example: Pseudomonas species.
- Found at the top of a tube with high oxygen concentration.
- Obligate Anaerobes:
- Grow poorly or not at all in the presence of oxygen.
- Example: Clostridium.
- Prefer low-oxygen environments, settling at the tube bottom.
- Facultative Anaerobes:
- Prefer oxygen for optimal growth but can survive without it.
- Example: Enterobacteriaceae bacteria.
- Concentrated at the top, utilizing aerobic respiration for more ATP.
Gaseous classification:
4) Microaerophiles
5) Aerotolerants
6) Capnophiles
- Microaerophiles:
- Require small amounts of free oxygen (10–15%) for growth.
- Cannot ferment or respire anaerobically and are harmed by high oxygen concentrations.
- Gather in the upper part of a test tube, avoiding the very top.
- Example: Campylobacter species.
- Aerotolerants:
- Grow without regard to oxygen presence.
- Metabolize energy anaerobically but are not harmed by oxygen.
- Distributed evenly throughout the test tube.
- Example: Streptococcus pyogenes.
- Capnophiles:
- Need relatively high concentrations of carbon dioxide for optimal growth.
- Example: Aggregatibacter species.
- No specific reference to oxygen preferences but thrive in elevated CO2 levels.
Three categories of chemoheterotrophs.
1)saprophytes: grow on dead organic material
2) Obligate parasite: requires a living host to grow in.
3) Facultative parasites: can live on dead or living organic material.
