Mutualism Commensalism Parasitism None of the above Question 11 1 / 1 pts A thick peptidoglycan layer forms a gram-positive cell wall. True False Question 12 1 / 1 pts
Which of the following steps are a part of Koch’s postulates? The suspected pathogen must be present in all cases of the diseasee The suspected pathogen must be isolated from the host and grown in pure culture The suspected pathogen must be able to causes the disease is a susceptible host The suspected pathogen must be isolated from the newly diseased host All are part of Koch’s postulates Incorrect Question 13 0 / 1 pts Which of the following describes the process of generalized transduction? A bacterium that is lysed can lead to chromosome fragments in the environment. A naturally competent bacterium that happens upon these DNA fragments can take up this DNA and integrate it into their genome. A prophage that becomes induced to excise itself from the host genome will occasionally take some of the host chromosome with it as it goes into the lytic cycle. When the new virus particles are made, they contain some bacterial genes that will then be transferred to other infected host bacteria. A lytic phage packs bacterial DNA of its host into new virus particle heads instead of the replicated viral genome. When this new phage particle infects a new host, the bacterial DNA from the original host can become integrated into the new host's genome via homologous recombination.
An F+ bacterium will build a hollow pilus that connects to an F- cell. The F plasmid then replicates and one strand is passed through the pilus into the recipient cell. The plasmid can then be inserted and integrated into the recipient's chromsome. Incorrect Question 14 0 / 1 pts Rolling circle replication is involved in _______. conjugation transformation specialized transduction generalized transduction Question 15 1 / 1 pts R plasmids confer what selective advantage to recipient cells? competence antiobiotic resistance protection from phage infection ability to photosynthesize
ability to form biofilms Question 16 1 / 1 pts The Ames test uses bacteria to investigate whether a substance is: mutagenic photosynthetic electronegative autotrophic Question 17 1 / 1 pts CRISPR loci are found in many species of bacteria and archaea are protective against: transduction antibiotics viral infection peroxides Question 18
0 / 1 pts What is horizontal gene transfer? How is it different than vertical gene transfer? Your Answer: Transmission Question 1 1 / 1 pts The area labeled with a green star is called the pseuodocoelom .
- Fall '19
- Bacteria, protostomes, Annelid