Bacteria and Archaea

1. Chapter 27 Bacteria and Archaea Questions prepared by William WischusenLouisiana State University Michael DiniTexas Tech University

2. Prokaryotes lack the nucleus found in eukaryotic cells. As a result, prokaryotic cells do not contain which of the following? • a nuclear membrane • DNA • one or more chromosomes • all of the above

3. Which of the following statements best describes most bacteria? • They are generally harmful. • They are limited to living in a few habitats. • They are very common in the environment. • They are responsible for the “common cold.”

4. Which features of bacteria can be considered to be defensive structures?

5. What are the features of prokaryotes that enable them to adapt so quickly?

6. Which of these is LEAST associated with prokaryotes engaged together in metabolic cooperation? • Mutualism • Biofilms • Symbiosis • Commensalism

7. What is true of archaeans? • They are the cause of many human diseases. • Structurally, they represent an intermediate form between bacteria cells and eukaryotic cells. • They are extremophiles. • They have undergone horizontal gene transfer with bacteria and with eukaryotes. • They include Earth’s first aerobic photosynthesizers.

8. Cyanobacteria that can perform nitrogen fixation • use this metabolic pathway to provide themselves with glucose. • cannot also perform aerobic photosynthesis. • provide both fixed nitrogen and fixed carbon dioxide to other organisms. • do so on membranes called thylakoids. • are part of the community of organisms at deep-sea vents.

9. A bacterium that contains both R plasmids and F plasmids • can transfer antibiotic resistance genes to other bacteria via conjugation. • must be pathogenic. • therefore has the ability to make and spread restriction enzymes to counter phage attacks. • is, therefore, an Hfr cell. • can undergo genetic recombination only by performing conjugation.