Biopsychology Flashcards
What are the key features and functions of the nervous system?
The nervous system is a specialized network of cells that serves as our primary communication system, using electrical and chemical signals.
FUNCTIONS:
To collect, process, and respond to environmental information.
To coordinate the workings of different organs and cells in the body.
In contrast, the endocrine system communicates through hormones.
What is the structure and function of the CNS?q
The brain and spinal cord form the central nervous system.
The brain is the center of conscious awareness.
The outer layer of the brain, the cerebral cortex, distinguishes higher mental functions from animals.
The brain has two hemispheres.
The spinal cord is an extension of the brain, responsible for reflex actions.
It passes messages to and from the brain and connects nerves to the PNS.
What is he structure and function of the PNS?
PNS transmits messages via millions of neurones to and form the nervous system
PNS divides into Autonomic and Somatic NS’s
What are the key features of the endocrine system?
works alongside nervous system to control vital functions in the body through the action of hormones
works more slowly than the nervous system but has widespread and powerful effects
What are glands?
organs in body that produce hormones
key glnd - pituitary gland controls release of hormones from other endocrine glands in body
What are hormones?
secreted in the blood stream
affect any cell in the body that has a receptor for that particular hormone
What does the sympathetic state do?
- increases heart rate
- increases breathing rate
- dilates pupils
- inhibits ddigestion
- inhibits saliva production
What does parasympathetic state?
- Decreases heart rate
- Decreases breathing rate
- Constricts pupils
- Stimulates digestion
- stimulates saliva production
What do the endocrine system and ANS do during a stressful event?
- stressor percieved from hypothalamus activates the pitutitary
- sympathetic nervous system is now aroused
- Adrenaline released from medulla into bloodstream, causes fight/flight response
- when threat passes, Parasympathetic NS takes over and reduces activities of the body that were increased by actions of the sympathetic branch
What is the structure and function of sensory neurones?
Carry messsages from PNS to CNS
long dendrites and short axons
located in PNS in clusters called ganglias
What is the structure and function of motor neurones?
connect CNS to effectors like muscles/glands
short dendrites and long axons
cell bodies may be in the CNS nut longer axond form part of PNS
Whar is the structure of the neurone?
cell body/soma - genetic material
dendrites - branch-like structures protrude from cell body. carry nerve impulses from neighbouring neurones towards cell body
axon - carries electrical impulses away from the cell body down the length of the neurone, protected by myelin sheath and nodes or ranvier speed uio transmission of the impulse
What is the structure and function of relay neurones?
connect sensory neurones to motor neurones. short dendrites and short axons
How does a neurone fire?
at resting state, inside is negatively-charged compared to the outside
when a neurone is activated, inside of cell becomes positively-charged for a split second causing
an action potential to occur
creates an electrical impulse that travels down axon towards the end of the neurone
What is a synapse?
gap between 2 neurones
What event occurs at the synapse?
when electrical impusle reaches end of neurone it triggers the release of neuroransmitter from tiny sacs called synaptic vesicles
once a neurotransmitter diffuses across the synapse, it is taken up by the postsynaptic receptor site on the next neuron so the impulse onl travels in 1 direction
What are neurotransmitters?
chemicals that diffuse across synapse to next neurone in chain
What neurotransmitters have an excitatory response?
Adrenaline -> increases positive charge of presynaptic neuron, increasing likelihood that post synaptic neuron will fire
Dopamine
What neurotransmitters have an inhibitory response?
Seretonin -> increasing negative charge of postsynaptic neurone, making it less likely the post synaptic neurone will fire
Dopamine
What is summation?
Excitatory and inhibitory influences are summed by the postsynaptic neuron.
To trigger an action potential, the total effect must reach a certain threshold.
If the overall effect of the neurotransmitter is inhibitory, the postsynaptic neuron is less likely to fire.
If the overall effect is excitatory, the postsynaptic neuron is more likely to fire.
What are 2 exmples of neurotransmitters?
- Acetyl choline - found where motor neurone meets a muscle, causing muscles to contract
- Seretonin - affects mood and social behaviour which is why it has been iimplicated as a cause of depression
What is localisation of function?
specific brain areas are responsible for specific functions
What hemisphere controls the right side of the body?
left
What is the cerebral cortex?
inner part of the brain
separates us from lower animals as it is highly developed