Nature vs Nurture Flashcards
What do heritability estimates measure, and why do they depend on the range of genotypes and environments?
Heritability estimates measure the proportion of variation in a population that is attributed to genetic differences.
Because the measure is a proportion it is dependant on the number of different genotypes and environments. An increase in either will cause an increase in variation thus reducing the heritability estimate.
What is PKU, what is its genetic basis, and what does it illustrate about the roles of genes
and environment in the development of the nervous system?
PKU is an inborn metabolic disorder that causes prefrontal lobe damage because of the inability to breakdown PKU sufficiently. It is caused by a single recessive gene on chromosome 12. It illustrates the role of environment as it is a contingent disease that with the change of diet, reduces the cognitive deficits caused by the toxic Phenylpyruvate in the blood stream.
Define “norms of reaction”.
Norms of reaction is a graph or list of relationships between the genotype, phenotype and environment.
Explain the difference between organisational and activational effects of hormones. Give
an example of each.
Organisational effects of hormones occur early on in the developmental process. Causing long-lasting, relatively irriversible effects. For example, giving female rodents a prenatal injection of testosterone lead to them displaying
Briefly describe Capsi et al (2002) study on the “Role of Genotype in the Cycle of Violence in Maltreated Children.”
Men in the Dunedin Study who had low levels of the geneotype MAOA, which metabolised neurotransmitters for Seretonin and Dopamine, and were also significantly maltreated as children between the age of 3 and 11 were significantly more likely to have violent behaviours as 26 year old men.
