1. Various research centers are studying identical twins in order to discover the “heritability” of behavioral characteristics – that is, the degree to which a trait is due to genes (“nature”) instead of environment. They have reached some surprising conclusions. One study found, for example, that optimism and pessimism are both very much influenced by genes, but only optimism is affected by environment, too. According to another study, genes influence our coffee consumption, but not consumption of tea. Anxiety (nervousness and worry) seems to be 40 to 50 percent heritable. Another study tells us that happiness does not depend much on money or love or professional success; instead, it is 80 percent heritable! Among the traits that appear to be largely heritable are shyness, attraction to danger (thrill seeking), choice of career, and religious belief.
2. It is not easy to discover the genes that influence personality. The acid that carries genetic information in every human cell, DNA, contains just four chemicals: adenine, cytosine, guanine, and thymine. But a single gene is “spelled out” by perhaps a million combinations. As the Human Genome Project (which provided a “map” of human genes) was almost complete in the spring of 2000, there were a number of newspaper headlines about specific discoveries: Gene Linked to Anxiety and Thrill Seeking Due to Genetics. The newspaper articles led people to believe that a single gene is responsible for a certain personality trait, in the same way a single gene can be responsible for a physical characteristic or disease. However, one gene alone cannot cause people to become anxious or thrill seeking. Instead, many genes work together, and they direct the combination of chemicals in the body. These chemicals, such as dopamine and serotonin (which affect a person’s mood), have a significant influence on personality.
3. If, indeed, personality traits are, on average, about 50 percent heritable, then environment still plays an important role. Unlike other animals, human beings have choice. If our genes “program” us to be anxious, we can choose a low-stress lifestyle or choose to meditate or do relaxation exercises. But because of the powerful influence of genes, most psychologists believe that there is a limit to what we can choose to do. Thomas Bouchard, a psychologist and the director of one twin study, says that parents should not push children in directions that go against their nature. “The job of a parent,” he says, “is to look for a kid’s natural talents and then provide the best possible environment for them.
3.What is the primary focus of research centers studying identical twins?
(1 Point)
Identifying the genetic basis of physical traits
Understanding the influence of environment on behavior
Determining the heritability of behavioral characteristics
Investigating the impact of diet on personality
4.According to one study mentioned in the text, how are optimism and pessimism influenced?
(1 Point)
Both optimism and pessimism are influenced by genes and environment.
only optimism is influenced by the environment.
Only pessimism is influenced by genes, while optimism is not.
Neither optimism nor pessimism is influenced by genes or environment.
5.What percentage of heritability is associated with happiness, according to the research?
(1 Point)
20%
40%
60%
80%
6.Which of the following traits appears to be largely heritable, as mentioned in the text?
(1 Point)
Coffee consumption
Choice of career
Tea consumption
Hair color
7.How does the text describe the influence of genes on personality traits?
(1 Point)
single gene can cause specific personality traits.
Many genes work together to influence personality.
Genes have no influence on personality.
Genes determine physical traits but not personality.
8.According to Thomas Bouchard, what is the role of parents in relation to their children's nature?
(1 Point)
Parents should push children to go against their natural talents.
Parents should not consider their children's natural talents.
Parents should provide the best possible environment based on their children's natural talents.
Parents should ignore their children's natural talents.
9.What is the main limitation of the Human Genome Project's findings with respect to personality traits?
(1 Point)
It provided a comprehensive map of human genes.
It identified the single gene responsible for each personality trait.
It underestimated the role of environment in personality.
It suggested that only one gene influences personality.
10.What is the main focus of text 3?
(1 Point)
Discussing the differences between animal and human genetics
Analyzing the heritability of personality traits
Exploring the impact of environment on behavior
Describing the Human Genome Project
11.Why do most psychologists believe there is a limit to what individuals can choose to do, as mentioned in paragraph 3?
(1 Point)
Because genes have no influence on behavior
Because environment completely determines behavior
Because genes have a powerful influence on behavior
Because individuals have unlimited choices
12.According to text 1, which personality trait is influenced by genes but not affected by the environment?
(1 Point)
Optimism
Pessimism
Coffee consumption
1 answer