Biological approach Flashcards
(37 cards)
Physiology
The study of the body and its parts and how they function
Purpose of biological approach
The biological approach combines psychology and biology to provide physiological explanations for human behaviour: how we think, feel and behave in terms of physical factors in the body
Assumptions of biological approach
Everything psychological is at first biological
The approach investigates how biological structures and processes within the body impacts on behaviour.
Much of human behaviour has a physiological cause, which may be genetically or environmentally altered.
Twin studies:
Psychologists are interested in studying twins in order to investigate the genetic basis of behaviour:
1. Monozygotic
2. Dizygotic
Monozygotic
One zygote - these twins are formed when a fertilised cell splits into two and forms two separate embryos
Dizygotic-
Two zygotes: these twins are formed when two separate eggs become fertilised by different sperm cells
Concordance rates
Agreement between(refers to the extent to which a pair of twins share similar traits of characteristics)
Concordance rates in MZ and DX twins
There should be 100% concordance rates between MZ twins if a particular characteristic/trait is a genetic one, but DZ twins will show lower concordance rates.
Family studies
Galton agreed any resemblance between family relatives could be a result of both genes and shared environment.
However, with alcoholism for example. there’s a suggestion of a biological predisposition to the addiction(more likely to develop this addiction).
Adoption studies
These studies involve comparing a trait or characteristic between adopted children and their biological or adoptive parents
Selective breeding
This method involves artificially selecting male and female animals for a particular trait.
These animals are then put together in order to breed and produce offspring.
Selective breeding has been used to demonstrate how a number of behavioural characteristics may have a genetic basis e.g. ‘maze bright’ rats
Genes
The basic units of heredity
How do genes function
Genes function in pairs, and the recombination of genes from parents to offspring provides the basis for genetic variability
Phenotype
Observable characteristics of an individual - depending on the interaction of genetic and environmental factors
Genotype
The potential for characteristics, determined by genes
Example of recessive gene
Gene for blue eyes
Example of dominant gene
Gene for brown eyes
Heterozygous
The genotype consists of two different genes
Homozygous
The genotype consists of two genes that are the same
Evolution
The changes in inherited characteristics in a biological population over successive generations
Two main concepts by Charles Darwin in evolutionary theory:
Natural selection
Sexual selection
Natural selection
Animals with particular traits that provide them with an advantage are more likely to survive and reproduce, thereby passing on their ‘adaptive traits’ to their offspring.
These behaviours need to adapt to the environment the animal’s living in, depending on three principles:
1. Principle of diversity
2. Principle of interaction
3. Principle of differential amplication
Principle of diversity
Variety within a species
Principle of interaction
How this variety of species adapt and fit in with the environment