Term
| List the three Domains of Life. |
|
Definition
|
|
Term
|
Definition
|
|
Term
| Discuss various characteristics of Domain Archaea. |
|
Definition
-Possess a number of features in common with the eukaryotic nucleus and cytoplasm, suggesting common ancestry.
-Membrane lipids linkages different from those in eukaryotes or bacteria. ---They have modified branched hydrocarbon chains.
--Archaea have ether linkages and eukaryotes and bacteria have ester linkages.
--Ether linkages are more resistant to heat and other extreme conditions. |
|
|
Term
| Discuss the characteristics of proteobacteria |
|
Definition
-Amazing diversity of form and metabolism
-They share molecular and cell-wall features
-5 major subgroups; α-proteobacteria, β-proteobacteria, γ-proteobacteria, δ -proteobacteria, ε –proteobacteria |
|
|
Term
| Discuss the characteristics of cyanobacteria |
|
Definition
-Photosynthetic bacteria abundant in fresh waters, oceans and wetlands and on surfaces of arid soils
-Named for their blue-green or cyan color
-The only prokaryotes that generate oxygen as a product of photosynthesis |
|
|
Term
| Define: Horizontal gene transfer |
|
Definition
| The process in which an organism receives genetic material from another organism without being the offspring of that organism |
|
|
Term
| Discuss the endosymbiosis theory on how mitochondria and plastids originated. |
|
Definition
| Theory that proposes that mitochondria and chloroplasts originated from bacteria that took up residence in early eukaryotic cells. |
|
|
Term
| Discuss prokaryotic cell cellular structure |
|
Definition
Prokaryotes have complexity of cellular structures resulting from adaptive evolution.
-Thylakoids
-Magnetosomes
=magnetite crystals-Act as compass needle-Helps to locate low-oxygen habitats |
|
|
Term
| Describe and identify bacterial cell shape and arrangement. |
|
Definition
5 major shapes:
-Spheres – cocci
-Rods – bacilli
-Comma-shaped – vibrios
-Spiral-shaped – spirochaetes are flexible while spirilli are rigid |
|
|
Term
| What is mucilage? What are its functions? |
|
Definition
-Sometimes called glycocalyx
-Composed of polysaccharides, proteins, or both.
-Secreted from cells.
-Mucilage has a variety of functions:
Evade host defenses
capsule
Hold colony together
Help aquatic species float in water. |
|
|
Term
|
Definition
| Test used to distinguish bacterial types based on the composition of their cell wall. |
|
|
Term
| Compare and contrast between Gram-positive and gram negative bacteria. |
|
Definition
pos- Relatively thick peptidoglycan layer.Thick cell wall absorbs and retains crystal violet and appear purple.Vulnerable to penicillin that interferes in cell wall synthesis.
neg- Less peptidoglycan and has a thin outer envelope of lipopolysaccharides.lipid bilayer, different from the plasma membrane. Lose the crystal violet, but retain safranin.Cells are stained red/pink. Resists penicillin. |
|
|
Term
| Define: pathogenic bacteria |
|
Definition
|
|
Term
| Describe the different ways prokaryotic cells move.Flagella, pilli |
|
Definition
Swim, twitch, glide or adjust floatation.
flagella- Prokaryotic flagella lack: microtubules, the motor protein dynein, and a plasma membrane covering. consists of Filament or tail, hook, and basal motor
pilli-Threadlike cell surface structures.Composed of the protein pilin.Can also play important roles in bacterial reproduction and disease processes: |
|
|
Term
|
Definition
-divide by splitting in two
-the basis for a widely used method of detecting and counting bacteria in samples |
|
|
Term
|
Definition
-Found in aquatic filamentous cyanobacteria.
-Develop when winter approaches.
-Survive winter and produce new filaments in spring. |
|
|
Term
|
Definition
-Tough protein coats that are produced inside bacterial cells and then released when the enclosing cell dies and breaks down.
-Amazingly long dormant span.
-Found in some Gram-positive bacteria. |
|
|
Term
|
Definition
| DNA may enter cells via a viral vector. |
|
|
Term
|
Definition
| Microbes are able to take up DNA directly from the environment. |
|
|
Term
|
Definition
| Genes are transferred directly from one prokaryote to another. |
|
|
Term
| List and describe the major types of bacteria and archaea based on energy and carbon source. |
|
Definition
Autotrophs
-Produce all or most of their own organic compounds.
Photoautotroph
-Uses light as energy source for synthesis of organic compounds from CO2 and H2O or H2S
-Cyanobacteria
Chemoautotrophs
-Use energy obtained from chemical modification of inorganic compounds to synthesize organic compounds.
-Only found in prokaryotes.
Heterotrophs
-Organisms that require at least one organic compound, and often more.
Photoheterotroph
-Able to use light energy to make ATP, but they must take in organic compounds from the environment.
-Only found in prokaryotes
Chemoheterotroph
-Must obtain organic molecules for both energy and as a carbon source.
-Found in most bacteria. |
|
|
Term
| List and describe the classifications due to oxygen response. |
|
Definition
Obligate aerobes
-Require oxygen for respiration and cannot grow without oxygen.
Facultative anaerobes
-Can use oxygen or can use fermentation when oxygen is absent.
Obligate anaerobes
-Are poisoned by oxygen.
Aerotolerant anaerobes
-Do not use oxygen, but are not poisoned by it. |
|
|
Term
| List and describe the ecological roles of bacteria. |
|
Definition
Bacteria and archaea are important in producing and degrading organic compounds.
Producers
-synthesize organic compounds used by other organisms as food.
Decomposers (saprobes)
-break down dead organisms to release minerals for reuse.
Methanogens
-are a group of anaerobic archaea that produce methane.
Methanotrophs
-are prokaryotes that consume methane. |
|
|
Term
| Define: Pathogenic bacteria |
|
Definition
| parasitic microbe that causes disease symptoms |
|
|
Term
|
Definition
| Organisms that obtain organic compounds from living hosts. |
|
|
Term
| List Koch’s postulates and for what purpose do we use his method? |
|
Definition
1.The presence of the pathogen must correlate with the occurrence of symptoms.
2.The pathogen must be isolated from an infected host and grown in pure culture.
3.Cells from the culture should cause disease when inoculated into a healthy host.
4.Should be able to isolate the same pathogen from the second infected host. |
|
|
Term
| List industrial uses of bacteria |
|
Definition
-Food production
-Bioremediation
-Fermentation
-Food preservation |
|
|
Term
| List and describe the classifications due to special metabolism. |
|
Definition
Diazotrophs
-conduct nitrogen fixation
-Removal of nitrogen from the gaseous phase
-Enzyme nitrogenase converts inorganic nitrogen gas (N2) into ammonia (NH3)
-Plants and eukaryotic algae depend on ammonia to make nitrogen containing compounds
-Rhizobium – bacteria that fix nitrogen
Heterocysts
-specialized cells for nitrogen fixation in cyanobacteria |
|
|
Term
| List and describe the symbiotic roles of bacteria. |
|
Definition
Symbiosis
-An organism that lives in close association with one or more other organisms.
Parasitism
-One partner benefits at the expense of the other.
Mutualism
-Symbiotic association that is beneficial to both partners. |
|
|
Term
|
Definition
Syntrophy
-some bacteria live together and supply each other with essential nutrients
Consortia
-larger community of nutrient exchangers
-Marine worm, Olavius algarvensis, has no mouth, gut, or anus and depends on bacteria inside it for food and waste recycling
Associations with eukaryotes
-Bacteria induces normal development in Ulva.
-Bioluminescent bacteria in squid and other animals. |
|
|
