Behavioural genetics/epigenetics Flashcards
(23 cards)
What is heredity?
Heredity is the passing of characteristics from one generation to the other through genes.
What are genes?
Genes are a part of the chromosome that carry information in the form of DNA (deoxyribonucleic acid is a thread-like chain of nucleotides).
What do genes carry instructions for?
Genes carry the instructions for particular characteristics such as temperament or intelligence.
What influences the expression of genes?
The way a gene is expressed in an individual is dependent upon environmental forces.
What is the nature-nurture debate?
The nature-nurture debate centers on the influence of genetics versus environmental factors on behavior.
What is genotype?
Genotype is the set of genes an organism carries in its cells.
What is phenotype?
Phenotype is an organism’s observable or expressed characteristics.
How is genotype expression influenced?
The expression of the genotype is influenced by environmental forces.
How is the influence of genetics studied?
The influence of genetic make-up and environmental forces is studied by determining the concordance rate between fraternal and identical twins and/or biological and adoptive parents.
What is concordance rate?
Concordance rate is the extent to which twins or parents share the same characteristics.
What are the concordance rates for twins?
There is a 50% concordance rate amongst identical (MZ) twins, and a 19% concordance rate for non-identical (DZ) twins for physical aggression.
What are twin studies used for?
Twin studies are a useful tool to differentiate the effects of genes and the environment on behavioral characteristics and liability to psychopathology and illness.
What are identical twins?
Identical twins (monozygotic or MZ twins) have identical DNA and thus the same genetic variants at all genes.
What can phenotypic differences between MZ twins be attributed to?
Phenotypic differences observed between MZ twins can be attributed to environmental factors.
How do dizygotic twins differ from identical twins?
Dizygotic or fraternal twins (DZ) share, on average, half of their genes, unlike identical twins.
What does the biological approach suggest about genetic similarities?
The biological approach suggests that genetic similarities in identical, non-identical, and family members govern the way one looks or behaves.
What is epigenetics?
Epigenetics is the idea that our environment and lifestyle can alter how our genes behave.
What does ‘EPI’ mean in epigenetics?
‘EPI’ means above or around the gene.
How do epigenetic changes occur?
Epigenetic changes can be triggered by lifestyle, environment, and age, and they can last for months or years.
What is the mechanism of epigenetics?
Epigenetics describes how genes can be switched off or on by chemical signals without altering the DNA.
How does epigenetics relate to behavior?
Epigenetics is a mechanism for regulating gene expression, allowing genes to be changed dynamically at a DNA level.
What have studies found about poor care during infancy?
Studies have found correlations between poor care during infancy and epigenetic changes that correlate with long-term impairments resulting from neglect.
How do identical twins illustrate epigenetics?
Identical twins share the same DNA, but their unique experiences in life will cause some genes to express themselves differently.
