Test Bank For PHYSICAL ANTHROPOLOGY 11TH EDITION BY PHILIP STEIN

Test Bank For PHYSICAL ANTHROPOLOGY 11TH EDITION BY PHILIP STEIN

CHAPTER 3

THE MODERN STUDY OF HUMAN GENETICS

While it is easiest to introduce the basic mechanisms of heredity by using examples from the world of plants and laboratory animals, we are most concerned with human evolution and human genetics. The fields of human and medical genetics have grown exponentially and today traditional Mendelian genetics would probably make up only a week’s study in a contemporary course on introductory genetics. We certainly do not have the time to examine most of the new developments in genetics. Chapter 3 attempts to focus more on human genetics and to present, in abbreviated form, some of the new developments. It also expands on the presentation of genetics in the previous chapter. This chapter does not have to be assigned, for the information in Chapter 2 is adequate for our evolutionary studies, but students enjoy learning about these subjects.

Chapter Summary

A large number of polymorphic blood proteins are found in the blood that are inherited in known Mendelian patterns. The best-known system of blood proteins is the ABO system, which consists of three basic blood antigens. Another well-known system is the Rh blood type system. These and other blood type systems used to be thought of as selectively neutral, but they are not.

Over 15,000 inherited traits have now been recognized in humans. Phenylketonuria is an example of an abnormality that is inherited as a simple recessive; achondroplastic dwarfism, on the other hand, is inherited as a simple dominant. Not all patterns of inheritance follow these simple Mendelian rules. One distinctive pattern of inheritance occurs when the gene in question is located on the X chromosome. Since males inherit one X chromosome from their mothers and one Y chromosome from their fathers, genes on the X chromosome are not paired as they are in females.

A number of abnormalities are not due to single genes but to errors in the number and structure of chromosomes. Such errors, when they involve autosomes, tend to lead to major abnormalities.

Today, diseases of genetic cause or influence have become the subject of a great amount of medical research. Already geneticists can, in a limited way, manipulate the human genome. In the future, human cloning, gene therapy, and other forms of genetic engineering may become common practices to cure genetic abnormalities, create children with specific characteristics, and allow couples to have special types of children.

Today, a gene is seen as a section of DNA that has a specific function, such as the coding of a particular protein, which might have a phenotypic expression or regulate the expression of another gene. One of the most ambitious ventures of the past decade is the Human Genome Project, the mapping of the entire human genome.

Student Learning Outcomes for Chapter 3

Upon satisfactory completion of Chapter 3, students should be able to:

1. Apply the basic principles of Mendelian genetics, cytogenetics, and molecular genetics to a wide range of human-based problems and issues.

2.  Understand the increasing importance of genetics in medicine.

Learning Objectives for Chapter 3

Upon satisfactory completion of Chapter 3, students should be able to:

1. Describe some of the contributions of genetics to medicine.

2. Explain the ABO blood system, including the relationship between the various genotypes and phenotypes, why blood type matters for blood transfusions, and how the ABO system differs from Mendelian inheritance.

3. Distinguish between the various causes of genetically based abnormalities.

4. Evaluate the various deviations from Mendelian inheritance, including the inheritance of X-linked traits.

5. Describe the causes and consequences of chromosomal abnormalities, including the two basic types.

6. Describe some of the many recent advances in genetics knowledge and the ethical dilemmas that accompany them.

7. Explain the concept of genetic engineering and discuss how this type of engineering may change humans in the future.

8. Explain what a gene is on the molecular level.

Chapter Outline

Medical Genetics

Blood-Type Systems

Human Inherited Abnormalities

Other Patterns of Inheritance

Chromosomal Abnormalities

Genetic Abnormalities as Mistakes in Proteins

Summary

Genetics and Human Affairs

Genetics and Medicine

The Control of Human Biological Evolution

Summary

Advances in the Molecular Study of Genetics

What is a Gene?

The Human Genome

Summary

Box 3-1   Sex and the Olympics

Box 3-2   Genetics and Insurance: An Ethical Dilemma

Box 3-3   Landmarks in Genetics: The First DNA Sequence of an Animal Genome is Decoded

Box 3-4   DNA Fingerprinting