Explain how both biochemical oxygen demand and chemical oxygen demand are measured
What will be an ideal response?
Answer: The biochemical oxygen demand is determined by highly oxygenating a water sample. The water is sealed in a bottle and incubated for 5 days at 20 °C in the dark. During this time, the organisms should not be limited by oxygen, so a respiration capacity is determined based on the quantity of organic material in the water sample. Chemical oxygen demand is measured by oxidizing all organic material into CO2 by using an oxidizing agent, and the loss of oxidizing agent is quantified to infer CO2 and therefore organic material concentration.
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If a microbe is said to "ferment sugar", this means that the microbe is breaking down a sugar for energy.
a. True b. False
Adenoviruses are one of the most common etiologic agents of lower respiratory tract infection among:
a. previously healthy patients 2 months to 5 years of age. b. adults younger than 30 years of age. c. community-acquired pneumonia in adults. d. school-age children.
In this depiction of transcription (accompanying figure), the ____ strand is ____ because it ____
a. upper; RNA; contains guanine b. upper; RNA; contains uracil c. lower; RNA; contains thymine d. upper; RNA; has no uracil e. lower; DNA; contains adenine
How is reverse transcriptase used to clone genes?
a. Reverse transcriptase is used to make a cDNA copy of an mRNA strand. b. Reverse transcriptase is used to make a cloned DNA copy of a plasmid DNA molecule. c. Reverse transcriptase is necessary to read the information contained on the cDNA molecule. d. Reverse transcriptase transcribes RNA from cDNA in reverse order. e. Reverse transcriptase transcribes cDNA into RNA without transcription of introns.