Microbio lecture 4
Match the Clostridial species with the diseases they cause:
- 1. Clostridium difficile- Antibiotic-assoiciated diarrhea disease - 2. Clostridium botulinum- Botulism, a disease characterized by flaccid paralysis. - 3. Clostridium tetani- Tetanus: a disease characterized by painful muscle spasms. - 4. Clostridium perfingens- Gas gangrene: a disease characterized by necrotic tissue and the production of gas.
Influenza viruses bud from the host cell. Based on this information, the viruses most likely
are envoloped
Expression of viral oncogenes in infected animal cells
can mimic proto-oncogenes, causing imbalance in cell cycle control towards unchecked proliferation, leading to tumor formation.
Based on what you know about the myxobacteria, for which of the following could they serve as an experimental model?
cell to cell communication and cooperation
Please order the following steps to reflect the order in which they occur in the replication cycle of an animal virus.
1. Adsorption (attachment) to host cell surface 2. Penetration and uncoating 3. Synthesis of viral nucleic acid and proteins 4.Assembly of viral particle 5. Release from host cell
Identify which of the following genera have members that are disease-causing facultative anaerobes.
- Escherichia Corynebacterium -Mycobacterium -Thermus -Staphylococcus
Place the steps of specialized transduction in order.
temperate phage injects its DNA into a bacteria host phage DNA intergrates into host cell DNA to become a prophage prophage excises from host chromosome, but takes some of the host genetic material with it replication/assembly produces defective particles hat carry some previous host DNA DNA of defective phage is injected into the new host but cannot cause a productive infection previous host bacterial DNA intergrated into new host's genome Integrated transferred bacterial DNA
Some phages are medically important for all of the following reasons EXCEPT -they serve as a model for general viral replication cycles. -they can destroy bacterial cells. -they also infect eukaryotic cells. -their genome may encode a toxin.
they also infect eukaryotic cells.
Rabies virus, which can be transmitted from animals to humans, is classified as a(n) ______ virus.
zoonotic
Members of the genus Mycoplasma have no cell wall, making them somewhat unique in the microbial world. How do they prevent osmotic lysis?
Their cytoplasmic membrane is rich in sterols to help provide added strength and rigidity.
Match each of the following aerobic chemolithotrophs with their characteristics.
- 1. Nitrifying bacteria- Gram-negative bacteria that obtain energy by oxidizing inorganic compounds like ammonia. - 2. Hydrogen-oxyidizing bacteria- Gram-negative obligate chemolithotroph, use H2 as an energy source with O2 as a terminal electron acceptor. - 3. Sulfur-oxidizing bacteria- Gram-negative rods / spirals, many form filaments, obtain energy by oxidizing hydrogen sulfide and thiosulfate with )2 as a terminal electron acceptor.
Match the description of obtaining nutrients from other organisms with the appropriate organism type.
- 1. Some Photobacterium and Vibrio speicies:- Form an endosymbiotic relationship with certain types of fish and squid.- The animals provide nutrients to the bacteria, and the bacteria provide bioluminescence that can be used as camouflage against predation. - 2. Epulopiscium species- Gram-positve, cigar-shaped bacteria that reside in the intestinal tract of surgeonfish in order to obtain nutrients.- Very large (for bacteria), with the unusual trait of possessing thousands of copies of the bacterial genome within the cell. - 3. Bedellovibrio species- Highly motile Gram-negative curved rods that prey on E. coli and other Gram-neagative bacteria.- The attacker from a hole in the cell wall of the target, enters, and consumes the cellular constituents of the target. - 4. Legionella species- Often reside in protozoa.- They are Gram-negative obligate aerobes that utilize amino acids from the eukaryotic host, but not carbo hydrates, as a source of carbon and energy
Which of the following statements about plant virus transmission are TRUE?
-Plant viruses enter their host through wounds, -Grafted plants may be at risk of virus infection, -An insect may transmit viruses between plants, -Parasitic fungi may transmit plant viruses
Which of the following characteristics can be utilized to classify and categorize viruses?
-Type of nucleic acid -Hosts infected -Strandedness of nucleic acid (positive/negative sense) -Capsid shape -Disease symptoms -Presence or absence of envelope
Match each of the following obligate aerobic bacteria with its description.
1. Pseudomonas species- Gram-negative rods with polar flagella.- Often produce pigments- Widespread in soil and water- Most are harmless, but some can be opportunistic pathogens of humans - 2. Thermus species- Stain Gram-negative, but have an unusual cell wall- Survive will in heat, due to their interesting heat-resistant enzymes. - 3. Deinococcus species- Stain Gram-positive- with an odd multilayer cell wall that lets the cell resist high levels of gamma radiation - (also due to their extensive DNA repair enzyme activities). - 4. Micrococcus species- Gram-positive cocci found in soil, dust particles, inanimate objects, and skin- tolerates dry and moderately salty conditions - 5. Mycobacterium species- Generally pleomorphic (variable shape) rods that stain poorly and resist destaining due to the waxy lipids in their cell wall structure- Several species cause human diseases
Which of the following is NOT a member of the Enterobacteriaceae family (Gram-negative rods, glucose fermenters, some members motile with peritrichous flagella, some members lactose fermenting)?
Corynebacterium diphtheriae
Select the FALSE statement regarding bacterial diversity. -Ti plasmid of agrobacterium is used to genetically engineer plants -Nitrogen fixing symbionts of legumes are genetically related to plant pathogens that cause crown gall -Myxobacteria are able to create fruiting bodies-Agrobacterium are able to transfer a piece of DNA to plant cells, which then express that DNA -During unfavorable conditions, myxobacteria travel as a pack to a new location.
During unfavorable conditions, myxobacteria travel as a pack to a new location.
Influenza vaccines must be changed yearly because the viral antigens change from year to year. Based on this information, which of the following is most likely true about the influenza virus?
It has an RNA genome.
Members of this group of microbes can break down glycogen deposited in the vaginal lining in response to estrogen. This helps to drop the pH in the area, preventing infections.
Lactic acid bacteria
Which of the statements is FALSE? -bacteria use quorum sensing to detect cell density -bacillus and clostridium species form endospores -some prokaryore species can survive autoclave temp. -some cyanobacteria can fix nitrogen -Rhizobia transfer some of their DNA to the host plant - The Argobacterium Ti plasmid is used to genetically engineer plants
Rhizobia transfer some of their DNA to the host plant
Which of the following are TRUE regarding purple sulfur bacteria, purple non-sulfur bacteria, and green sulfur bacteria?
They are anoxygenic phototrophs. They all use sunlight as an energy source. They live in environments rich in oxygen. They are aquatic and use water as a source of electrons for making reducing power for biosynthetic reactions.
Please choose the statement that best describes the role of viral surface proteins or spikes.
Viral spikes provide means of attachment to host cell surface.
Corynebacterium species and Enterobacteriaceae family members are examples of ______ anaerobes, meaning that they preferentially use aerobic respiration if O2 is available, but can ferment if it is not.
facultative
Haemophilus influenzae is a virus that causes the "flu."
false
Only Gram-positive bacteria can form resting stage structures. Group starts
false
Which of the following contains only one type of macromolecule? i. RNA viruses ii. DNA viruses iii. Prions iv. Viroids v. RNA and DNA viruses
iii and iv
A virus usually infects only certain types of cells due to
interactions between viral and cellular surface molecules.
After beta phage infects Corynebacterium diphtheriae and integrates its DNA into the host genome, the bacterium is capable of causing the disease diphtheria. Which term best describes this phenomenon?
lysogenic conversion