Ch 8: Genetic Variability & Mutation

About This Chapter

Watch videos and refresh your knowledge of genetic variability and mutation. Video lessons present info in a simple and clear manner and come with self-assessment quizzes for further review.

Genetic Variability and Mutation - Chapter Summary

Gene mutations and genetic variability are central concepts in the study of evolution and adaptation, as well as being critical to our understanding of various gene-related illnesses and disorders. This comprehensive examination of genetic variation dives into the myriad ways genes are modified, deleted, and rearranged, producing the great diversity we observe throughout biological science. Our chapter covers the following concepts:

  • Genetic variation through meiosis and fertilization
  • Chromosomes: inheritance, sex determination, mutation, and rearrangements
  • Mutagens and environmental effects on mutation rates
  • Mutations: frameshift mutations and the effect of mutations, insertions, and deletions on protein function and DNA
  • Cancer syndromes and genetic risk factors
  • Genetic variability, random mutation, and genetic drift
  • Inborn errors of metabolism
  • Synapsis and meiosis/mitosis crossing over

We provide training through short video lessons--taught by expert instructors--that are easy to understand. Along with these video lessons, we present you with supplementary quizzes and an end-of-chapter exam that reveal your strengths and weaknesses through instantaneous feedback. You can also use your quiz results to help you determine if you need to return to specific lesson materials to further your comprehension.

14 Lessons in Chapter 8: Genetic Variability & Mutation
Test your knowledge with a 30-question chapter practice test
How Meiosis & Fertilization Promote Genetic Variation

1. How Meiosis & Fertilization Promote Genetic Variation

Individuals are different because of their genetic variation. Even two siblings who come from the same parents have different genetic make-ups. This variation comes from both meiosis and fertilization, which are components of sexual reproduction.

The Chromosome Theory of Inheritance: Segregation and Independent Assortment

2. The Chromosome Theory of Inheritance: Segregation and Independent Assortment

Mendel proposed the law of segregation and the law of independent assortment to explain the inheritance behind his pea plant traits. A hundred years later, Boveri and Sutton developed the chromosome theory of inheritance, which stated that chromosomes were responsible for the heredity Mendel observed. Learn about these men and their ideas in this lesson.

Sex Determination, X-Inactivation, and Barr Bodies

3. Sex Determination, X-Inactivation, and Barr Bodies

Sex determination, X-inactivation and Barr bodies are complex chromosomal processes. Learn more about each of these processes and test your knowledge with a quiz.

Cytoplasmic & Mitochondrial Inheritance: Types & Impacts

4. Cytoplasmic & Mitochondrial Inheritance: Types & Impacts

Everyone knows that you inherit genetic information from your parents, but did you know there are multiple ways for this to occur? In this lesson, we'll look at extranuclear inheritance and see what this means for passing on DNA.

Mutagens: How the Environment Affects Mutation Rates

5. Mutagens: How the Environment Affects Mutation Rates

What causes mutations to occur in living things? How do we avoid mutations? Are mutations always bad? Discover answers to these questions and more in this lesson on mutagens.

Effects of Frameshift Mutations: Definitions and Examples

6. Effects of Frameshift Mutations: Definitions and Examples

What is a frameshift in genetic translation? How can a frameshift mutation change a protein? In this lesson, learn about the codon reading frame and how frameshift mutations cause serious problems for polypeptide formation.

Effects of Mutations on Protein Function: Missense, Nonsense, and Silent Mutations

7. Effects of Mutations on Protein Function: Missense, Nonsense, and Silent Mutations

How does a tiny point mutation change the way a protein works? What are the consequences of base substitutions? In this lesson, we'll use an imaginary creature to explore missense, nonsense and silent mutations.

What is a Point Mutation? - Definition, Causes & Types

8. What is a Point Mutation? - Definition, Causes & Types

What are genetic mutations? How do they affect our DNA? This lesson covers the basics of point mutations and provides simple examples of different mutation types.

Cancer Syndromes & Genetic Risk Factors for Cancer

9. Cancer Syndromes & Genetic Risk Factors for Cancer

This lesson describes something called cancer syndrome or family cancer syndrome, as well as the important clues that can help it be detected and two examples of such a condition.

Chromosomal Rearrangement

10. Chromosomal Rearrangement

Have you ever switched out one thing for another or traded places with someone? Our chromosomes can do this, too. This lesson tells you how as we go over chromosomal rearrangements!

Genetic Variability and Random Mutation

11. Genetic Variability and Random Mutation

Evolution is driven by variation among populations. The amount of variability determines how well a population can adapt to environmental changes, while random mutations can provide new variations that help a population adapt to unexpected changes.

What Are Inborn Errors of Metabolism?

12. What Are Inborn Errors of Metabolism?

Inborn errors of metabolism are genetic disorders that affect the metabolism of food components. Many of these disorders are difficult to diagnose but must be caught early in order to be treated. Learn about a common disorder, phenylketonuria.

Genetic Drift: Definition, Examples & Types

13. Genetic Drift: Definition, Examples & Types

Genetic drift reduces genetic variability of a population by decreasing the size of the population. The change in population size and variability often leads to new species and unique populations.

Synapsis & Crossing Over in Meiosis

14. Synapsis & Crossing Over in Meiosis

This lesson will cover synapsis and crossing over that occur during the process of meiosis. We'll look at exactly when these occur and how they can lead to greater genetic diversity.

Chapter Practice Exam
Test your knowledge of this chapter with a 30 question practice chapter exam.
Not Taken
Practice Final Exam
Test your knowledge of the entire course with a 50 question practice final exam.
Not Taken

Earning College Credit

Did you know… We have over 200 college courses that prepare you to earn credit by exam that is accepted by over 1,500 colleges and universities. You can test out of the first two years of college and save thousands off your degree. Anyone can earn credit-by-exam regardless of age or education level.

To learn more, visit our Earning Credit Page

Transferring credit to the school of your choice

Not sure what college you want to attend yet? Study.com has thousands of articles about every imaginable degree, area of study and career path that can help you find the school that's right for you.

Other Chapters

Other chapters within the MCAT Test: Practice and Study Guide course

Support