Concepts of Genetics (12th Edition)
Concepts of Genetics (12th Edition)
12th Edition
ISBN: 9780134604718
Author: William S. Klug, Michael R. Cummings, Charlotte A. Spencer, Michael A. Palladino, Darrell Killian
Publisher: PEARSON
bartleby

Concept explainers

bartleby

Videos

Textbook Question
Book Icon
Chapter 12, Problem 1NST

In bacteriophages and bacteria, the DNA is almost always organized into circular (closed loops) chromosomes. Phage λ is an exception, maintaining its DNA in a linear chromosome within the viral particle. However, as soon as this DNA is injected into a host cell, it circularizes before replication begins. What advantage exists in replicating circular DNA molecules compared to linear molecules, characteristic of eukaryotic chromosomes?

HINT: This problem involves cm understanding of eukaryotic DNA replication, as discussed earlier in the text (see Chapter 11). The key to its solution is to consider why the enzyme telomerase is essential in eukaryotic DNA replication, and why bacterial and viral chromosomes can be replicated without encountering the “telomere” problem.

Expert Solution & Answer
Check Mark
Summary Introduction

To explain: The advantages of replication of DNA in a circular form compared to the linear form.

Introduction: In almost all the organisms, DNA is the genetic material that is inherited from one generation to the next. Depending on the species, DNA exists as a linear or circular molecule. In bacterial species, almost always, DNA is present as a circular chromosome. Viruses contain either DNA or RNA as their genetic material.

Explanation of Solution

In bacterial species, DNA is mostly present in circular form rather than linear form. Circular DNA serves certain advantages over the linear form. Some of the advantages of circular DNA over linear DNA are as follows:

  • Circular DNA molecules are more stable compared to the linear molecules.
  • End regions of linear DNA are more prone to degradation by intracellular enzymes.
  • Linear DNA molecules have an unprotected OH group. This increases the chances of chemical degradation of linear DNA molecules.
  • Circular DNA does not show DNA loss, as seen in linear DNA molecules. Linear DNA has telomerase, which shortens after every cell cycle.
Conclusion

Thus, circular DNA is more advantageous than linear DNA because it is more stable than the linear DNA molecules.

Want to see more full solutions like this?

Subscribe now to access step-by-step solutions to millions of textbook problems written by subject matter experts!
Students have asked these similar questions
The following table is from Kumar et. al. Highly Selective Dopamine D3 Receptor (DR) Antagonists and Partial Agonists Based on Eticlopride and the D3R Crystal Structure: New Leads for Opioid Dependence Treatment. J. Med Chem 2016.
The following figure is from Caterina et al. The capsaicin receptor: a heat activated ion channel in the pain pathway. Nature, 1997. Black boxes indicate capsaicin, white circles indicate resinferatoxin. You are a chef in a fancy new science-themed restaurant. You have a recipe that calls for 1 teaspoon of resinferatoxin, but you feel uncomfortable serving foods with "toxins" in them. How much capsaicin could you substitute instead?
What protein is necessary for packaging acetylcholine into synaptic vesicles?

Chapter 12 Solutions

Concepts of Genetics (12th Edition)

Knowledge Booster
Background pattern image
Biology
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, biology and related others by exploring similar questions and additional content below.
Similar questions
SEE MORE QUESTIONS
Recommended textbooks for you
Text book image
Biology Today and Tomorrow without Physiology (Mi...
Biology
ISBN:9781305117396
Author:Cecie Starr, Christine Evers, Lisa Starr
Publisher:Cengage Learning
Text book image
Biology: The Dynamic Science (MindTap Course List)
Biology
ISBN:9781305389892
Author:Peter J. Russell, Paul E. Hertz, Beverly McMillan
Publisher:Cengage Learning
Text book image
Human Heredity: Principles and Issues (MindTap Co...
Biology
ISBN:9781305251052
Author:Michael Cummings
Publisher:Cengage Learning
Text book image
Concepts of Biology
Biology
ISBN:9781938168116
Author:Samantha Fowler, Rebecca Roush, James Wise
Publisher:OpenStax College
Text book image
Biochemistry
Biochemistry
ISBN:9781305577206
Author:Reginald H. Garrett, Charles M. Grisham
Publisher:Cengage Learning
Text book image
Biology 2e
Biology
ISBN:9781947172517
Author:Matthew Douglas, Jung Choi, Mary Ann Clark
Publisher:OpenStax
What Is A Virus ? ; Author: Peekaboo Kidz;https://www.youtube.com/watch?v=YS7vsBgWszI;License: Standard YouTube License, CC-BY