Chapter 15: Problem 1

In this chapter, we focused on how gene mutations arise and how cells repair DNA damage. At the same time, we found opportunities to consider the methods and reasoning by which much of this information was acquired. From the explanations given in the chapter, (a) How do we know that mutations occur spontaneously? (b) How do we know that certain chemicals and wavelengths of radiation induce mutations in DNA? (c) How do we know that DNA repair mechanisms detect and correct the majority of spontaneous and induced mutations?

Short Answer

Expert verified

Answer: Spontaneous mutations are changes in DNA structure that occur without an external cause. They can be studied in experimental settings by continuously observing an organism's offspring without exposure to external mutagens. Researchers often use model organisms with short generation times, such as bacteria or yeast, which reproduce asexually, making it easier to observe changes in their DNA that arise without any external factors.

Step by step solution

(a) Understanding Spontaneous Mutations

Spontaneous mutations are changes in DNA structure that occur without an external cause. They can be observed throughout generations by continuously studying an organism's offspring without exposure to external mutagens. Various experimental settings help to demonstrate the occurrence of these mutations, like using model organisms with short generation times. For instance, researchers may study bacteria or yeast, which reproduce asexually, making it easier to observe changes in their DNA that arise without any external factors.

(b) Identifying Chemicals and Radiation that Induce Mutations

To understand how certain chemicals and wavelengths of radiation cause mutations in DNA, researchers expose organisms to different chemicals or radiation sources and observe the changes in their DNA. By comparing the DNA of exposed organisms to the DNA of unexposed control groups, researchers can identify specific chemicals or wavelengths that cause changes in DNA structure and increased mutational rates. This allows them to establish a causal relationship between exposure to specific agents and the occurrence of mutations in DNA.

(c) Studying DNA Repair Mechanisms

To determine how DNA repair mechanisms detect and correct the majority of spontaneous and induced mutations, researchers study organisms with defective DNA repair systems. By comparing the mutation rates of organisms with functional repair systems to those with defective ones, scientists can estimate the efficiency of repair mechanisms in detecting and correcting mutations. Additionally, experiments can be designed to study how individual repair proteins function and interact with DNA, revealing their roles in the repair process. As a result, researchers can further understand the specifics of how DNA repair mechanisms detect and correct mutations.

Unlock Step-by-Step Solutions & Ace Your Exams!

Full Textbook Solutions
Get detailed explanations and key concepts
Unlimited Al creation
Al flashcards, explanations, exams and more...
Ads-free access
To over 500 millions flashcards
Money-back guarantee
We refund you if you fail your exam.

Start your free trial

Over 30 million students worldwide already upgrade their learning with Vaia!

Recommended explanations on Biology Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Short Answer

Step by step solution

(a) Understanding Spontaneous Mutations

(b) Identifying Chemicals and Radiation that Induce Mutations

(c) Studying DNA Repair Mechanisms

One App. One Place for Learning.

Most popular questions from this chapter

Recommended explanations on Biology Textbooks

Biological Structures

Cells

Cell Communication

Responding to Change

Biological Organisms

Reproduction

Study anywhere. Anytime. Across all devices.