BIOL 240 - UW - FINAL EXAM NEWEST ACTUAL

BIOL 240 - UW - FINAL EXAM NEWEST ACTUAL /

QUESTIONS AND ANSWERS VERIFIED/GRADED A+

Methylotrophs - ----Answers---Oxidize C1 compounds. No C- C bonds (non-organic) e.g. CH2OH, HCOOH, CH4, CH3NH2 Viroids - ----Answers---Consist only of naked RNA (just nucleic acids). Extremely small (less than 400 nucleotides).High degree of internal complementarity (lots of folds).Resistant to ribonucleases. RNA polymerase finds a viroid and tries to make more of it and it never comes off, it just goes around and around the circle. So far, only observed to cause disease in plants

Prions - ----Answers---Proteinaceous infectious particles.No nucleic acid, no genes... just protein. Proteins miss-fold and cause a chain reaction causing more protein to miss-fold and making the host very sick. Different "infectious" agent.Responsible for transmissible spongiform encephalopathies (TSEs), such as mad cow disease. Prion replication method still unclear. Thought to revolve around conversion of protein conformations from normal to abnormal form over time

Virology Today - ----Answers---Virology and medicine are closely involved. Cancer-causing oncoviruses (e.g., HPV).Cancer-destroying oncolytic viruses. Gene therapy. Virology continues to be involved in examination of emerging global diseases

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CRISPR - ----Answers---Clusters of regularly interspaced short palindromic repeats. Bacteria do not want to be infected by viruses. Many bacteria have these internal CRISPRs.CRISPR Associated Genes are always on the lookout for virus DNA. If they find any, they chop it up and then they add it to their genome (deactivated) so that if they see the virus again they can recognize it and the know to attack. This can also replace one DNA sequence with another DNA sequence

Suggested Prion Replication - ----Answers---A PrPSc (scrapie) prion protein contacts a PrPc protein. The PrPSc induces a conformational change in the PrPc converting it to a prion. A few PrPSc convert many PrPc into prions. Prions form fibrils, thought to lead to disease.

Which is the only method that allows you to count all virus particles, whether they are infectious or not? - ----Answers-- -Electron microscopy

The plaque assay for determining viral titer measures only ___ viral particles - ----Answers---Infectious

What is the most reliable way to identify a virus? - ---- Answers---Nucleic Acid Analysis

True or False - Viroids and prions are not viruses. Viroids can infect animals.. Dimitri Ivanovski first discovered viruses. - --- -Answers---True, False, True. Viroids infect plants.

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Which of the following can be found in the peptidoglycan layer of gram-negative bacteria? - ----Answers---NAG and NAM

A human feels sick and asks about the pathogens cell wall.Which cell wall composition can you rule out? - ----Answers- --NAG and NAT (these are archaea)

Physiological Diversity - ----Answers---Is the result of 4 billion years of evolution

Metabolic Diversity - ----Answers---If there is a niche to exploit, microbes have adapted to exploit it. These niches are different ways of getting energy from light, organic compounds, etc. Limited only by constraints of chemistry and physics

Catabolism - ----Answers---Releases energy

Anabolism - ----Answers---Consumes energy to build things like cell components and macromolecules

Macronutrients - ----Answers---Required by ALL cells to build macromolecules. C, N, P, S, O

Micronutrients - ----Answers---Required by some cells.Includes Fe, Cu, Na, Mg, Mn, and others. It's hard to think of an organism that doesn't require iron, so maybe it is a borderline case between macronutrient and micronutrient 3 / 4

Fundamentals of Nutrition - ----Answers---Energy Source, Electrons, and Carbons Source Methanotrophs - ----Answers---Are methylotrophs capable of oxidizing methane (CH4) to methanol. Methane monooxygenase (MMO). Intracytoplasmic membranes. Obligate C1 utilizers. Obligate aerobes, often microaerophilic.Widespread in soil and water, morphologically diverse

Methanotroph Environments - ----Answers---Aquatic and terrestrial habitats. Often at interface between anoxic (where methane is formed) and oxic (needed for respiration) zones.Frequently observed at the thermocline (e.g., lake water columns). Found in cattle rumen, swamps. Although high CH4, Ó often too low

Nutrifiers - ----Answers---Use reduced N compounds as energy sources (e-donors). Capable of autotrophic growth (chemolithoautotrophs). Scattered in 4 of 5 subdivisions

Nutrifiers - Nitrosococcus, Nitrosomonas - ----Answers--- Ammonia oxidizers, Ammonia monooxygenase

Nutrifiers - Nitrobacterand Nitrospira - ----Answers---Nitrite oxidizers, Nitrite oxidase

FISH - ----Answers---Detecting nitrifying bacteria in activated sewage sludge by FISH. Two types of bacteria co- occur in nature. Fluorescent dye-tagged phylogenetic probes

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