Concept explainers
In the following diagram of lytic and lysogenic cycles, describe steps numbered 1-8 and label structures a-e.
To list and describe: The following diagram is of lytic and lysogenic cycle.
Introduction: Virus is an infectious agent that cannot be seen through the naked eyes. Virology is the study of viruses and virologists are the biologists who study viruses. Viruses are obligate intracellular parasites because it needs a living host cell for replication. Obligate intracellular parasites do not have the ability to reproduce outside their host cell.
Answer to Problem 1IQ
Pictorial representation: The lytic and lysogenic cycle is shown in Fig.1.
Fig.1: Lytic and lysogenic cycle
Explanation of Solution
Phages can infect and reproduce in the host cell by either of the two cycles— lysogenic cycle and lytic cycle. The lytic cycle is also known as virulent cycle, whereas the lysogenic cycle is a nonvirulent cycle. Attachment, penetration, uncoating, replication, assembly, and release are the steps involved in the replication of virus.
- During attachment and penetration, the virus attaches to a host cell and injects its genetic material into the host cell.
- During uncoating, the viral DNA or RNA enters to the nucleus of host cell and takes control over it.
- The host cell synthesizes the viral components.
- The newly-created virus release from the host cell either by lysis of cell, waiting for the cell to die, or by budding through cell membrane.
- In the lysogenic cycle, the phage DNA integrates to the bacterial chromosome and become prophage.
- Prophage is the genetic material of a bacteriophage that is incorporated to the genome of a bacterium and is able to produces phage if specifically activated.
- The bacteria reproduce by passing the prophage to daughter cells and a large population of infected bacteria forms.
- The prophage exits from the bacterial chromosome and starts the lytic cycle.
In lytic cycle, the viral DNA does not integrate with the bacterial DNA, but it destroys the host DNA and takes over the cellular replicative machinery in order to reproduce its own genome. In the lytic cycle, after the replication process is over, the host cell wall is lysed and new virions are released, whereas in the lysogenic cycle the virus does not destroy the host cell. It remains dormant and rarely produces virions during unfavorable conditions.
Want to see more full solutions like this?
Chapter 19 Solutions
Biology - Study Guide
Additional Science Textbook Solutions
Anatomy & Physiology
Microbiology: An Introduction
Campbell Biology (10th Edition)
Biology Illinois Edition (Glencoe Science)
Essentials of Genetics (9th Edition) - Standalone book
Microbiology Fundamentals: A Clinical Approach
- How is host cell lysis triggered after bacteriophage invasion? What are the outcomes to bacterial host physiology if the bacteriophage undergoes the lysogenic cycle?arrow_forwardWith regard to promoting the lytic or lysogenic cycle, what wouldhappen if the following genes were missing from the λ genome?A. croB. cIC. cIID. intE. cII and croarrow_forwardLet’s suppose a drug inhibits the function of the N protein. Would such a drug favor the lysogenic cycle, favor the lytic cycle, or prevent both cycles from occurring?arrow_forward
- How does lambda excise and replicate during the lytic cycle? Explain the factors that determinelysis vs. lysogeny.arrow_forwardHow is a lysogenic cycle different from a lytic cycle?arrow_forwardchicken pox and shingles Include whether each is capable of the lytic and/or lysogenic life cycle and what each of these mean.arrow_forward
- What environmental conditions favor a switch to the lytic cycle?arrow_forwardWhat are the steps of the lytic cycle? How do the lytic and lysogenic cycles differ? How are they similar? please answer short.arrow_forwardThe five stages of the bacteriophage lytic cycle occur in this order:a. penetration, attachment, release, maturation, biosynthesis.b. attachment, penetration, release, biosynthesis, maturation.c. biosynthesis, attachment, penetration, maturation, release.d. attachment, penetration, biosynthesis, maturation, release.e. penetration, biosynthesis, attachment, maturation, release.arrow_forward
- What is the difference between the lytic pathway and the lysogenic pathway?arrow_forwardFigure 21.10 Which of the following statements is false? In the lytic cycle, new phages are produced and released into the environment. In the lysogenic cycle, phage DNA is incorporated into the host genome. An environmental stressor can cause the phage to initiate the lysogenic cycle. Cell lysis only occurs in the lytic cycle.arrow_forwardIn _______, viral DNA becomes integrated into a bacterial chromosome and is passed to descendant cells. a. binary fission c. the lysogenic pathway b. the lytic pathway d. conjugationarrow_forward
- Biology 2eBiologyISBN:9781947172517Author:Matthew Douglas, Jung Choi, Mary Ann ClarkPublisher:OpenStax