Exam 27: Bacteria and Archaea

Compared to eukaryotes, prokaryotes are ________.

Data were collected from the heterocysts of a nitrogen-fixing cyanobacterium inhabiting equatorial ponds. Study the graph and choose the most likely explanation for the shape of the curve.

Genetic variation in bacterial populations cannot result from

Foods can be preserved in many ways by slowing or preventing bacterial growth. Which of these methods should be least effective at inhibiting bacterial growth?

The figure below depicts changes to the amount of DNA present in a recipient cell that is engaged in conjugation with an Hfr cell. Hfr cell DNA begins entering the recipient cell at Time A. Assume that reciprocal crossing over occurs (in other words, a fragment of the recipient's chromosome is exchanged for a homologous fragment from the Hfr cell's DNA). - During which two times can the recipient accurately be described as "recombinant" due to the sequence of events portrayed in the figure?

What is the goal of bioremediation?

The figure below depicts changes to the amount of DNA present in a recipient cell that is engaged in conjugation with an Hfr cell. Hfr cell DNA begins entering the recipient cell at Time A. Assume that reciprocal crossing over occurs (in other words, a fragment of the recipient's chromosome is exchanged for a homologous fragment from the Hfr cell's DNA). - How is the recipient cell different at Time D than it was at Time A?

A hypothetical bacterium swims among human intestinal contents until it finds a suitable location on the intestinal lining. It adheres to the intestinal lining using a feature that also protects it from phagocytes, bacteriophages, and dehydration. Faecal matter from a human in whose intestine this bacterium lives can spread the bacterium, even after being mixed with water and boiled. The bacterium is not susceptible to the penicillin family of antibiotics. It contains no plasmids and relatively little peptidoglycan. This bacterium derives nutrition by digesting human intestinal contents. Thus, this bacterium is an ________.

Bacteria perform each of the following ecological roles. Which role typically does not involve symbiosis?

Which of the following traits do archaeans and eukaryotes share?

The figure below depicts changes to the amount of DNA present in a recipient cell that is engaged in conjugation with an Hfr cell. Hfr cell DNA begins entering the recipient cell at Time A. Assume that reciprocal crossing over occurs (in other words, a fragment of the recipient's chromosome is exchanged for a homologous fragment from the Hfr cell's DNA). - Which two processes are responsible for the shape of the curve at Time B?

A hypothetical bacterium swims among human intestinal contents until it finds a suitable location on the intestinal lining. It adheres to the intestinal lining using a feature that also protects it from phagocytes, bacteriophages, and dehydration. Faecal matter from a human in whose intestine this bacterium lives can spread the bacterium, even after being mixed with water and boiled. The bacterium is not susceptible to the penicillin family of antibiotics. It contains no plasmids and relatively little peptidoglycan. The cell also lacks F factors and F plasmids. Which of the following statements about the bacteria is most probably accurate?

When a virus infects a bacterial cell, often new viruses are assembled and released when the host bacterial cell is lysed. If these new viruses go on to infect new bacterial cells, the new host cells may not be lysed. What is the most plausible explanation for this?

The following table depicts characteristics of five prokaryotic species (A-E). Use the information in the table to answer the following question. - Which species is capable of directed movement?

Recently, a microbe that is able to digest cellulose was discovered in a hot spring with an average temperature of 95°C. Predict the group to which this microbe most likely belongs.

You have found a new prokaryote. What line of evidence would support your hypothesis that the organism is a cyanobacterium?

In this eight-year experiment, 12 populations of E. coli, each begun from a single cell, were grown in low-glucose conditions for 20,000 generations. Each culture was introduced to fresh growth medium every 24 hours. Occasionally, samples were removed from the populations, and their fitness in low-glucose conditions was tested against that of members sampled from the ancestral (common ancestor) E. coli population. - The cells in the 12 cell lines grown in low-glucose conditions showed the effects of which of the following processes?

The following table depicts characteristics of five prokaryotic species (A-E). Use the information in the table to answer the following question. - How many of these species probably have a cell wall that consists partly of an outer membrane of lipopolysaccharide?

Use of synthetic fertilisers often leads to the contamination of groundwater with nitrates. Nitrate pollution is also a suspected cause of anoxic "dead zones" in the ocean. Which of the following might help reduce nitrate pollution?

A hypothetical bacterium swims among human intestinal contents until it finds a suitable location on the intestinal lining. It adheres to the intestinal lining using a feature that also protects it from phagocytes, bacteriophages, and dehydration. Faecal matter from a human in whose intestine this bacterium lives can spread the bacterium, even after being mixed with water and boiled. The bacterium is not susceptible to the penicillin family of antibiotics. It contains no plasmids and relatively little peptidoglycan. -In which feature should one be able to locate a complete chromosome of this bacterium?