Biopsychology
1)nervous system and the endocrine system
Nervous system- consists of CNS and PNS. Communicates using electrical signals
Central nervous system (CNS)-consists of the brain and spinal cord and is origin of all complex
commands and decisions
Peripheral nervous system (PNS)- sends info to CNS from the outside world and transmits
messages from the CNS to muscles and glands in the body
Somatic nervous system (SNS)-transmits info from the receptor cells in the sense organs to the
CNS. Also receives info from the CNS that directs muscles to act
Autonomic nervous system (ANS)-transmits info to and from internal bodily organs. It is
‘autonomic’ as the system operates involuntarily. 2 main divisions: sympathetic and
parasympathetic nervous system
The nervous system
● Collect, process and respond to information in the environment
● Coordinate working of different organs and cells in the body
The central nervous system (CNS)
Brain has conscious awareness (cerebral cortex is outer layer), highly developed in humans
Spinal cord connects brain to PNS, responsible for reflex actions
The peripheral nervous system (PNS)
Autonomic nervous system (ANS) governs vital functions (breathing, heart rate, digestion)
Somatic nervous system (SNS) governs muscle movement and receives info from sensory
receptors
The endocrine system
Endocrine system-one of the body’s major info systems that instructs glands to release
hormones into bloodstream, hormones carried towards target organs in body, comms via chems
Gland-organ in body that synthesises substances (hormones)
Hormone-biochemical substance that circulates in the blood but affects target organs. Produced
in large quantities but disappear quickly. Effects very powerful
Fight or flight response-way an animal responds when stressed. Body becomes physiologically
aroused in readiness to fight an aggressor or flee
Adrenaline-hormone produced by adrenal glands which is part of the human body’s immediate
stress response system. Has strong effect on the cells of the cardiovascular system- stimulates
heart rate, contracting blood vessels and dilating air passages
The endocrine system
Glands and hormones
Endocrine system and nervous system control vital functions. Thyroid gland produces hormones
which are distributed into the bloodstream. (Thyroid gland produces thyroxine(hormone) which
increases heart rate and metabolic rates which affects growth rates).
Pituitary gland controls release of hormones from all endocrine glands in body
Endocrine and ANS working together: Fight or flight
Hypothalamus activates pituitary gland which triggers sympathetic branch activity of ANS. ANS
changes from normal resting state (parasympathetic state) to sympathetic state
Adrenaline- triggers physiological changes in body creating arousal for fight or flight response
, Immediate and automatic- acute response and automatic reaction
Parasympathetic action- once threat gone, parasympathetic nervous system goes to normal
2)Neurons and synaptic transmission
Neuron-nerve cells that process and transmit messages via electrical and chemical signals
Sensory neurons-carry messages from PNS to CNS, have long dendrites and short axons
Relay neurons-connect sensory neurons to motor or other neurons, short dendrites +long axons
Motor neurons-connect CNS to effectors (muscles and glands), short dendrites and long axons
The structure and function of neurons
100 billion neurons, transmits electrically and chemically
Types of neurons
3 types: sensory neurons, relay neurons and motor neurons
Structure of a neuron
Cell body contains nucleus, has dendrites which carry nerve impulses from neurons to cell
body
Axon covered in myelin sheath (protects axon and speeds electrical transmission of the
impulse. Divided by nodes of Ranvier (speeds up impulse transmission).
End of axon are terminal buttons
Location of neurons
Motor neuron’s cell bodies is in CNS, long axons form part of PNS. Sensory neurons located
outside of CNS (ganglia). Relay neurons make up 97% of all neurons and found within brain
Electrical transmission- firing of a neuron
When neuron is activated by a stimulus, inside of the cell becomes positively charged for a split
second causing an action potential to occur creating electrical impulse travelling down axon
towards end of neuron
Synaptic transmission
Synaptic transmission-process where neighbouring neurons communicate by sending chem
messages across synapse
Neurotransmitter-brain chemicals released from synaptic vesicles that relay signals across
synapse from one neuron to another
Excitation-when neurotransmitter (adrenaline) increases positive charge of postsynaptic neuron
Inhibition-when neurotransmitter (serotonin) increases negative charge of postsynaptic neuron
Chemical transmission
Neural networks (neurons comm with each other). Each neuron separated by synapse. Signals
in neurons are electrically transmitted. Signals between neurons are transmitted chemically
across synapse. When electrical impulse reaches the end of the neuron (presynaptic terminal)
It triggers release of neurotransmitters from synaptic vesicles
Neurotransmitters
Postsynaptic receptor site receives neurotransmitters from dendrites of adjoining neuron.
Specialist functions, e.g. acetylcholine for muscle contraction.
Excitation and inhibition
Adrenaline is excitatory, serotonin is inhibitory
Summation
Postsynaptic neuron triggered if sum of excitatory and inhibitory signals reach threshold
1)nervous system and the endocrine system
Nervous system- consists of CNS and PNS. Communicates using electrical signals
Central nervous system (CNS)-consists of the brain and spinal cord and is origin of all complex
commands and decisions
Peripheral nervous system (PNS)- sends info to CNS from the outside world and transmits
messages from the CNS to muscles and glands in the body
Somatic nervous system (SNS)-transmits info from the receptor cells in the sense organs to the
CNS. Also receives info from the CNS that directs muscles to act
Autonomic nervous system (ANS)-transmits info to and from internal bodily organs. It is
‘autonomic’ as the system operates involuntarily. 2 main divisions: sympathetic and
parasympathetic nervous system
The nervous system
● Collect, process and respond to information in the environment
● Coordinate working of different organs and cells in the body
The central nervous system (CNS)
Brain has conscious awareness (cerebral cortex is outer layer), highly developed in humans
Spinal cord connects brain to PNS, responsible for reflex actions
The peripheral nervous system (PNS)
Autonomic nervous system (ANS) governs vital functions (breathing, heart rate, digestion)
Somatic nervous system (SNS) governs muscle movement and receives info from sensory
receptors
The endocrine system
Endocrine system-one of the body’s major info systems that instructs glands to release
hormones into bloodstream, hormones carried towards target organs in body, comms via chems
Gland-organ in body that synthesises substances (hormones)
Hormone-biochemical substance that circulates in the blood but affects target organs. Produced
in large quantities but disappear quickly. Effects very powerful
Fight or flight response-way an animal responds when stressed. Body becomes physiologically
aroused in readiness to fight an aggressor or flee
Adrenaline-hormone produced by adrenal glands which is part of the human body’s immediate
stress response system. Has strong effect on the cells of the cardiovascular system- stimulates
heart rate, contracting blood vessels and dilating air passages
The endocrine system
Glands and hormones
Endocrine system and nervous system control vital functions. Thyroid gland produces hormones
which are distributed into the bloodstream. (Thyroid gland produces thyroxine(hormone) which
increases heart rate and metabolic rates which affects growth rates).
Pituitary gland controls release of hormones from all endocrine glands in body
Endocrine and ANS working together: Fight or flight
Hypothalamus activates pituitary gland which triggers sympathetic branch activity of ANS. ANS
changes from normal resting state (parasympathetic state) to sympathetic state
Adrenaline- triggers physiological changes in body creating arousal for fight or flight response
, Immediate and automatic- acute response and automatic reaction
Parasympathetic action- once threat gone, parasympathetic nervous system goes to normal
2)Neurons and synaptic transmission
Neuron-nerve cells that process and transmit messages via electrical and chemical signals
Sensory neurons-carry messages from PNS to CNS, have long dendrites and short axons
Relay neurons-connect sensory neurons to motor or other neurons, short dendrites +long axons
Motor neurons-connect CNS to effectors (muscles and glands), short dendrites and long axons
The structure and function of neurons
100 billion neurons, transmits electrically and chemically
Types of neurons
3 types: sensory neurons, relay neurons and motor neurons
Structure of a neuron
Cell body contains nucleus, has dendrites which carry nerve impulses from neurons to cell
body
Axon covered in myelin sheath (protects axon and speeds electrical transmission of the
impulse. Divided by nodes of Ranvier (speeds up impulse transmission).
End of axon are terminal buttons
Location of neurons
Motor neuron’s cell bodies is in CNS, long axons form part of PNS. Sensory neurons located
outside of CNS (ganglia). Relay neurons make up 97% of all neurons and found within brain
Electrical transmission- firing of a neuron
When neuron is activated by a stimulus, inside of the cell becomes positively charged for a split
second causing an action potential to occur creating electrical impulse travelling down axon
towards end of neuron
Synaptic transmission
Synaptic transmission-process where neighbouring neurons communicate by sending chem
messages across synapse
Neurotransmitter-brain chemicals released from synaptic vesicles that relay signals across
synapse from one neuron to another
Excitation-when neurotransmitter (adrenaline) increases positive charge of postsynaptic neuron
Inhibition-when neurotransmitter (serotonin) increases negative charge of postsynaptic neuron
Chemical transmission
Neural networks (neurons comm with each other). Each neuron separated by synapse. Signals
in neurons are electrically transmitted. Signals between neurons are transmitted chemically
across synapse. When electrical impulse reaches the end of the neuron (presynaptic terminal)
It triggers release of neurotransmitters from synaptic vesicles
Neurotransmitters
Postsynaptic receptor site receives neurotransmitters from dendrites of adjoining neuron.
Specialist functions, e.g. acetylcholine for muscle contraction.
Excitation and inhibition
Adrenaline is excitatory, serotonin is inhibitory
Summation
Postsynaptic neuron triggered if sum of excitatory and inhibitory signals reach threshold
