Straighterline Micro 250 Final Prep 227 Questions with

Straighterline Micro 250 Final Prep 227 Questions with Correct Answers Which class of eukaryotic microorganisms can be subdivided into groups such as Mastigophora, Sarcodina, Ciliophora, and Apicomplexa?

• Helminths
• Algae
• Protozoa
• Fungi - Correct Answers Protozoa

Genetic material can be excised from one chromosome and directly integrated into another via

• conjugation.
• transformation.
• transduction.
• transposons. - Correct Answers transposons.

Which immune cell secretes numerous cytokines that help to coordinate the response of other immune cells?

• B cell
• TH cell
• TC cell 1 / 4

• Platelets - Correct Answers TH cell

Which of the following enzymes are used to amplify DNA during PCR?

• restriction endonuclease
• DNA polymerase
• reverse transcriptase
• DNA ligase - Correct Answers DNA polymerase

In the nitrogen cycle, which of the following steps involves removal of nitrogen from the atmosphere by bacteria? - Correct Answers nitrogen fixation, In nitrogen fixation, nitrogen is removed from the atmosphere by nitrogen-fixing bacteria and converted to ammonia.If enough h+ ions are added to pure water to raise the H+ concentration of the solution to ten times higher than the original concentration, what is the resulting OH- concentration of the solution? - Correct Answers 10 -8M Fungi are able to reproduce asexually by creating conidiospores and sporangiospores. Which of the following is an accurate explanation for why it is advantageous that they are also capable of sexual reproduction?

Select one:

• Asexually produced offspring are more likely to compete for resources and will kill off the parental

fungi.

• Fungi normally produce sexually but produce asexually in harsh conditions such as severe drought.
• Offspring from two parents may have variations in form and function that contribute to survival of

the species.

• Sexual reproduction produces more offspring at a faster rate than spore formation. - Correct

Answers Offspring from two parents may have variations in form and function that contribute to survival of the species. 2 / 4

In a laboratory bacterial cell culture that has been infected by a virus, plaques are areas in which

Select one:

• bacterial cells are resistant to the virus and have not been infected.
• there is no nutrient available for the bacteria to grow.
• the virus has spread and left behind the remains of dead cells.
• the virus has not yet spread to that area of cells. - Correct Answers the virus has spread and left

behind the remains of dead cells.The sun's energy is delivered as discrete packets that travel as waves and are called

Select one:

• ATP.
• carotenoids.
• NADP.
• photons. - Correct Answers photons.

Which of the following is a characteristic of aerobic respiration?

Select one:

• Oxygen-containing ions act as the final electron acceptors in electron transport.
• The process includes glycolysis, the Krebs cycle, and the electron transport chain.
• Aerobic respiration produces a total of 2 ATP molecules.
• Aerobic respiration produces lactic acid. - Correct Answers The three stages of aerobic respiration

are glycolysis, the Krebs cycle, and the electron transport chain.n completing protein synthesis in a prokaryote, what basic message is carried by a specialized codon that has no corresponding tRNA?

Select one:

• "Fold peptide chain."
• "Terminate here."
• "Add cofactor."
• "Clip starting amino acid." - Correct Answers "Terminate here." The specialized codon signals the

end of protein synthesis; there is not RNA because it is only needed if the process is to continue. 3 / 4

Microbial drug resistance can be caused by mutations or by introduction of new genes into a population. Which of the following can only be caused by the introduction of new genes into a population?

Select one:

• a metabolic pathway in the bacterium is shut down
• binding sites for the drug are reduced in number or affinity to the drug
• new enzymes that inactivate the drug are synthesized
• uptake of the drug into the bacterium is diminished - Correct Answers new enzymes that

inactivate the drug are synthesized. This can only occur if new genes are introduced into the population.Why do the hands, feet, and breasts have more lymphatic vessels for host defense than other areas of the human body?

Select one:

• They have a high risk for infection due to frequent contact.
• They have a greater density of nerves.
• They require complex movement of fluids from the extremities.
• They are located a long distance from the thalamus. - Correct Answers They have a high risk for

infection due to frequent contact.Penicillin functions as an antimicrobial agent by inhibiting bacterial

Select one:

• cell wall synthesis.
• folic acid synthesis.
• protein synthesis.
• RNA and DNA function. - Correct Answers cell wall synthesis. Penicillin belongs to a class of

antibacterial agents that interfere with the production of the material that makes up the bacterial cell wall. The bacteria must constantly replace this material or they will become susceptible to rupture due to osmotic pressure.If enough ions are added to pure water to raise the concentration of the solution to ten times higher than the original concentration, what is the resulting concentration of the solution? - Correct Answers

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