BIO 250 Final Exam Questions With 100% Correct Answers Graded A+ 2024

1. What microbial process was responsible for changing Earth's atmosphere from one without oxygen to one with oxygen? Oxygenic photosynthesis 2. In the nitrogen cycle, which of the following phases involves the release of Nitrogen into the Earth's atmosphere? Denitrification 3. Farmers commonly inoculate legume crops with Rhizobium bacteria for which of the following purposes? The two form a symbiotic relationship increasing the plant's access to nitrogen. 4. In the secondary phase of wastewater treatment, why is air injected into the sludge as it is stirred and recirculated? The bioremediators need oxygen 5. Which of the following microorganisms is used to make yogurt? Lactobacillus bulgaricus 6. ATP is a Nucleotide that releases and stores energy in the cell 7. A viral capsid is composed of Proteins 8. Which of these are NOT considered living organisms? Viruses 9. Which of the following describes the order in which different types of RNA are involved in translation? Messenger RNA (mRNA), transfer RNA (tRNA), ribosomal RNA (rRNA) 10. What is the bacterial identification technique that, when positive, results in the bacterium staining two contrasting colors? Gram staining 11. Which of the following is found in some, but not all groups of eukaryotic microorganisms? Cell wall 12. In which instance would a researcher need to use Bergey's Manual of Systematic Bacteriology instead of Bergey's Manual of Determinative Bacteriology? To investigate the genetic history of a bacterial species 13. Which of the following structures is found in gram-negative bacteria but is absent from gram- positive bacteria? Outer lipid membrane 14. Which type of archaea is able to survive in extremely high concentrations of salt? Halophiles 15. Which of the following is true of prokaryotes, but not true of eukaryotes? They have cell walls made of peptidoglycan 16. Which of the following is the role of ribosomes? Provide a site for protein synthesis 17. Which of the following are theorized to be the ancestors of chloroplasts? Cyanobacteria 18. Which eukaryotic microorganisms are photoautotrophs? Algae 19. Describe the genetic material that is contained within a virus. RNA or DNA, but not both 20. In the life cycle of an animal virus, what occurs during adsorption? The virus attaches to receptor sites outside the host cell. 21. Which of the following viral enzymes converts viral RNA into DNA? Reverse transcriptase 22. A bacteriophage is what type of microorganism? Virus 23. What is the key function of a microbe's cell membrane, also known as the cytoplasmic membrane? It transports nutrients in and wastes out 24. The outer covering of a virus is called the Capsid 25. Which bacterial cell structure helps in locomotion? Flagellum 26. What organism relies only on inorganic minerals without sun for its nutrition? Lithoautotroph 27. What must a microbe do in active transport to absorb nutrients? Expend energy 28. Why is phosphorous an important nutrient for bacteria? It is a component of nucleic acids. 29. During which cycle of batch culturing are growing cells most vulnerable to a change in heat? Rapid growth 30. What is the main process by which bacterial cells reproduce? Binary fission 31. Appendages possessed by some bacteria that aid in conjugation are called which of the following? Pili 32. Which of the following processes results in the synthesis of cell molecules and structures? Anabolism 33. How is it possible for green sulfur bacteria that live on the ocean floor—where no sunlight can reach—to carry on photosynthesis? They get light from geothermal radiation 34. Which of these bacteria perform photosynthesis? Cyanobacteria 35. Which type of RNA transports the DNA master code to ribosomes? Messenger (mRNA)