Essays For AS Approaches
Outline and Evaluate the Biological Approach
According to the biological approach, behaviour is affected by genetics (including
evolution), biological structures and neurochemistry. Each individual has 23
pairs of chromosomes which are directly inherited from their birth parents, and
while the genotype (genetic make-up) is a highly significant aspect of the genetic
element of the biological approach, the phenotype of the individual is equally as
important, consisting of the person’s observable characteristics (such as eye
colour) and ultimately being determined by both the genotype and the
environment. The biological approach additionally distinguishes between
monozygotic and dizygotic twins. Monozygotic twins are 100% identical, are
always the same gender, and are sourced from the same, individual fertilised
egg.. Dizygotic twins, on the other hand, are only 50% identical, and can be the
same or different gender. As they are only 50% identical, dizygotic twins are
fraternal (non-identical). The concordance rate measures the agreement
between twins; if a shared behaviour is more prevalent in MZ twins than it is in
DZ twins, then the aforementioned behaviour is due to shared genetics over
circumstantial factors. In regards to evolution, this is defined as a random
physical ad behavioural change to a species over successive generations that
either enables it to adapt to its environment and survive or become maladaptive
and die out. If the change increases the chance of survival and reproduction then
these strong genes will be passed on to the next generation via natural selection.
In terms of biological structures, neurons are nerve cells with transfer
information within the nervous system, which takes the form of either the
central nervous system (CNS), which comprises the brain and spinal cord and is
responsible for controlling the individual’s physiology (breathing, heart beat,
senses), or the peripheral nervous system (PNS), which collects information
from the environment (temperature, pain, threat). Therefore, the PNS sends and
receives information to/from the CNS. The PNS consists of both the autonomic
nervous system (ANS) and the somatic nervous system (SNS). While the former
is important for survival and affects the reaction to threat, the latter is vital for
movement and comprises the muscles attached to the skeleton. The ANS can
further be broken down into the sympathetic and parasympathetic nervous
systems, with the former dealing with ‘Fight or Flight’ responses and the latter
facilitating homeostasis. The endocrine system, on the other hand, is an element
that maintains the level of hormones in the blood and other bodily fluids through
the glands. For example, the pituitary gland is known as the master gland and
controls the secretion of hormones. Finally, neurochemistry encompasses the
diffusion of neurotransmitters via cerebral fluid and the effects that the levels of
certain neurotransmitters can have upon behaviour. For example, low levels of
serotonin are associated with OCD, while high levels of dopamine are associated
with schizophrenia.
In an evaluative sense, there are evident aspects of validity that are applicable to
the biological approach. Primarily, as it adopts scientific methods for
investigation, the results that it yields are largely precise and objective, and it
utilises replicable experiments that can establish cause and effect between
