Chapter 3 – Nature v. Nurture
______study how heredity and environment interact to influence psychological characteristics.
______containing ______are situated in the nucleus of a cell.
Segments within DNA consist of ______that make proteins to determine our development.
A ______is the set of complete instructions for making an organism, containing all the genes in that organism (human genome makes us human, and the genome for drosophila makes it a common house fly).
Studying the effects of heredity and environment on two sets of twins, identical and fraternal, has come in handy. ↑ Behavior geneticists’ study identical and fraternal twins to determine the role of genes in behavior, personality, etc. ↓
Critics of separated twin studies note that such similarities
- can be found between strangers.
- can be a result of placement of separated twins into similar families
- are based on a few examples as opposed to a wide range of examples
In response, the separated twin researchers point out that differences between ______twins are greater than ______twins.
______are used to study the effects of nurture/environment on behavior, personality, etc.
- Adoptees tend to have ______personality traits to their birth parents than to their adoptive families
- Furthermore, siblings (biologically related or not) do not tend to show the same personality traits.
- But, children (adopted or not) tend to show similar attitudes, values, morals, political tendencies as do the ______
- Adopted children tend to be very well-adjusted people!
______refers to a person’s stable emotional reactivity and intensity.
Identical twins express ______temperaments, suggesting heredity predisposes temperament.
______refers to the extent to which the differences among people are attributable to genes (if the environment is equal, then the results between two individuals would be more attributable to genetic factors (high heritability) or, if the environment is vastly different, but the genetic factors similar, the results would be due to low heritability).
If genetic influences help explain individual diversity in traits, can the same be said about group differences?Not necessarily (individual differences in weight and height are heritable and yet nutritional influences have made westerners heavier and taller than their ancestors were a century ago).
Some human traits are fixed, such as having two eyes. However, most psychological traits ______with environmental experience.Genes provide choices for the organism to change its form or traits when environmental variables change. Therefore, genes are pliable or self-regulating (genes react to the environmental conditions).
Genes can influence traits which affect responses, and environment can affect gene activity. ______(a genetic predisposition that makes a child restless and hyperactive evokes an angry response from his parents. A stressful environment can trigger genes to manufacture neurotransmitters leading to depression).