Biopsychology
NERVOUS SYSTEM AND ENDOCRINE SYSTEM
Explain the difference between the nervous system and the endocrine
system (3 marks)
NS- network of cells in the human body which collects and responds to
environmental information picked up by our central and peripheral nervous
systems and coordinates the functions of bodily organs and cells
ES- controls vital functions in the body, various glands produce hormones
which are secreted into the bloodstream and targets organs and cells with
receptors for the hormone, these create responses e.g., thyroxine affects
heart rate and insulin affects blood glucose levels, the ES’s master gland is
the pituitary gland (controls hormone release)
Identify and describe two glands of the endocrine system (4 marks)
Pituitary gland- master gland, controls release of hormones from the
body’s endocrine glands, located in the brain
Adrenal gland- releases adrenaline when body is faced with an aggressor,
threat or stressor, increases heart rate, dilates pupils, and increases
breathing rate, releases adrenaline during the fight or flight response
Identify two hormones and briefly outline their functions (4 marks)
Adrenaline- released from the adrenal gland when body is faced with an
aggressor, threat or stressor, increases heart rate, dilates pupils, and
increases breathing rate, releases during the fight or flight response
Insulin- secreted by the pancreas, increases blood glucose levels
Identify and outline two divisions of the peripheral nervous system (4
marks)
Autonomic Nervous system- branches into the parasympathetic and
sympathetic nervous systems, governs vital bodily functions e.g., breathing,
heart rate, digestion
Somatic Nervous system- governs muscle movement and receives
information from sensory receptors
, Using an example, explain what is meant by the fight or flight response
(4 marks)
When the body is faced with a threat or aggressor, the hypothalamus
activates the pituitary gland which triggers the branches in the autonomic
nervous system, the body changes from a parasympathetic state to a
sympathetic state, where your body becomes physically aroused. The stress
hormone adrenaline is released from the adrenal medulla into the
bloodstream, this triggers physiological changes in the body e.g., increased
heart rate and breathing. This occurs immediately as soon as the threat is
detected and is an automatic bodily response. Once the threat has passed,
the parasympathetic nervous system returns the body to its resting state,
lowering heart rate and slowing breathing, amongst other physiological
changes.
NEURONS AND SYNAPTIC TRANSMISSION
Outline one difference between a sensory and a relay neuron (2
marks)
Sensory neuron- carries nerve impulses from receptors to the spinal cord
and brain, OR has long dendrites and short axons
Relay neuron- allows the sensory and motor neurons to communicate,
relays information between the two, OR has short dendrites and short axons
Briefly describe the structure of a neuron (3 - 4 marks)
The cell body contains a nucleus, which contains genetic material of the
cell. Branchlike structures called dendrites protrude from the cell body and
carry nerve impulses from neighbouring neurons towards the cell body. The
axon carries the impulses away from the cell body down the length of the
neuron and is covered in a fatty layer called the myelin sheath, which
protects the axon and speeds up electrical transmission of the impulse. The
myelin sheath is segmented by gaps called nodes of Ranvier, which speed
up transmission of the impulse by forcing it to ’jump’ across gaps in the
axon. At the end of the axon are terminal buttons that communicate with
the next neuron across the synapse.
Explain the process of synaptic transmission (4 marks)
Electrical impulses reach the synaptic terminal of the pre-synaptic neuron.
These impulses then trigger the release of neurotransmitters as a chemical
message. The neurotransmitters then cross the synapse from vesicles on the
