Biological approach Flashcards
Gene
A part of the chromosome of an of an organism that carries info in the form of DNA
The influence of genes on behavior
.
Genotype
The genetic make-up of an individual. This is inherited (height). Cannot simply be determined by observing the phenotype.
Phenotype
The observable characteristics of an individual. This is a consequence of the interaction of the genotype with the environment. (growing tall due to diet)
Twin studies
MZ (identical twins 100% shared genes)
DZ (Non-identical twins about 50% shared genes)
Concordance rate
The likelihood of one twin having the same characteristic as another
Example of twin study.
Mz twins blue eyes= 100% concordance and schizophrenia has 48% concordance rate.
Dz twins= 4%concordance rate for schizophrenia
This shows a possible genetic component to behaviour.
Evolution and behaviour
.
Evolution
refers to the change over successive generations due to adaption to the environment.
Darwin (1858) Natural selection theory
The variancy of species most adapted to the environment has an advantage in survival (aggression) and reproduction (relationships)
Attachment
Lorenz
The 3 biological structures that influence behaviour
The brain, the endocrine system and the nervous system.
The endocrine system
A chemical messaging system that releases hormones throughout the body.
the nervous system
carries messages throughout the body using neurons..
Comprised of the PNS and CNS
Hormones
Chemical from the pituitary glands secreted into the blood stream, influencing many different processes including mood
Strength 1 (importance of a scientific method)
- Experiments are in highly controlled environment so it is easily replicated adding to validity.
- Case studies used to be the go to studies for brain functioning but involved research bias and lack of control.
- Sophisticated imaging and recording has increased the precision and objectivity of the experimental method.
Strength 2 (Applications of the approach)
- Provides clear predictions . e.g the effects of neurotransmitters to those who are genetically related.
- real world applications e.g neurochemical imbalances leading to drug treatments for depression.
- e.g research into cardiac rhythms and their effect on mental well-being
Weakness 1 (reductionist)
- e.g explanations of mental disorders being reduced to gnes and chemical imbalances.
- This doesnt allow for a full understanding of behaviour as it doesnt take other factors into account.
- Factors such as cognitive, cultural and emotional.
Weakness 2 (problems withn evolution explanation)
- Most human behaviours can be transmitted by both genetic and cultural routes which complicates the evolutionary exlanation of behavior.
- many argue patterns of human behavior was purely based on culture and not the need to survive.
- e.g incest existing in most societies.
- However most most cultures have strict moral codes at an attempt to remove such taboos.
