Bio psych- the nervous system Flashcards
What is the peripheral nervous system split up into?
Somatic and autonomic
What is the central nervous system split up into?
Brain and spinal cord
How do Reflex Arcs work?Hint- there are 4 steps
1)Receptor in the skin detects a stimulus (the change in temperature).
2)Sensory neuron sends electrical impulses to a relay neuron, which is located in the spinal cord of the CNS.
3)Motor neuron sends electrical impulses to an effector.
4)Effector produces a response (muscle contracts to move hand away.
very brief5 step reflex arc in order
5 step reflex arc in order
1)sensor
2)sensory neuron
3)control center (spinal cord/relay neuron)
4)motor neuron
5)muscle (effector)
SNS is made up of ___ cranial nerves
12
SNS is made up of ___ spinal nerves
31
What does the SNS do (brief one sentence)
Connects the CNS to our senses
2 main components of SNS
Sensory and motor
What is the purpose of the sensory component- afferent pathways of the SNS
To transmit and receive information from the senses such as visual information from the eyes and auditory information from the ears to brain (sensory neurons).
What do the motor components of the SNS control | efferent pathways
direct voluntary movement of skeletal muscles that orchestrate all of our movements from brain (motor neurons)
What is the autonomic nervous system responsible:
Responsible for functions that keep the body in a stable state (homeostasis)
Control centre of the ANS
Top of the brain stem (hypothalamus and pituitary)
2 branches of the ANS
1) sympathetic branch
2) parasympathetic branch
What does the do Sympathetic branch
Activates and prepares body for rapid action when exposed to threats.Slows down other non-essential processes that consume energy e.g digestion
What does the parasympathetic branch do
Tries to store and conserve resources once the emergency has passed. Returns the body to a normal/balanced statedFor example, slows down heart rate.
3 key differences between the ANS and SNS
1) ANS is involuntary whereas the SNS is under conscious control
2) SNS has both sensory and motor neurons
3) ANS controls internal organs/ glands of the body, while the SNS controls skeletal muscle, and movement etc
What is a neurotransmitter?
Chemicals that are released from neurons and allow them to communicate with each other, and relay messages to different areas/structure
Synaptic transmission| 7 steps
1)Dendrite picks up the message (the NT) it sends an action potential through the cell body and along the axon to the terminal buttons
2)Once potential has arrived at the terminal buttons at the end of the axon, it needs to be transferred to another neuron. Must cross the synaptic gap.
3)At the end of the terminal buttons there are synaptic vesicles that contain and store NTs. These NT are chemical messengers that convert the electrical impulse to a chemical message that’s transferred to the next neuron
4)As the impulse (action potential) travelling to the end of the neuron reaches the synaptic vesicle, they release the NT that then crosses the synaptic gap. 5)As the NT diffuses across the synaptic gap it binds to specialised receptors on dendrites of the next cell that recognise it and match that particular cell.
6)Once the next cell is activated the receptor molecules produce either an excitatory effect (that strengthens further impulses) or inhibitory effect (that weakens further impulses) at a post synaptic level. 7)Synaptic transmission is completed (in a fraction of a second) by a process called re-uptake. This is where the NT is taken back up / recycled by the presysnaptic neuron.
What does the endocrine system do with and example
The endocrine system functions to secrete hormones in the blood stream to regulate many of our bodily functions. Works with the nervous system to coordinate physiological processes E.g releases melatonin from the pineal gland that induces sleepiness and relaxation
How does the endocrine system work
Provides a chemical system of communication via bloodstream It’s a network of glands spread throughout the body that manufacture and secrete chem messages throughout the body.DOES NOT USE NERVES
Growth hormones target organ
Anterior pituitary
Adrenocortical trophic hormone (ACTH) target organ
Anterior pituitary, adrenal cortex
When is the fight or flight activated
When we are exposed to a short term threat
What happens when the body appraises a situation-fight or flight
Hippocampus and amygdala try to recognise emotional reactions to stimuli and access stored memory of potential danger
What happens if a situation is appraised as potentially stressful- fight or flight response
The hypothalamus is alerted, SAM pathway activated
Effects of adrenalin
1) increased perspiration to balance body temp
2) increased heart rate for increased blood flow
3) pale complexion as blood is diverted from surface of skin to internal organs
4) increased pupil dilation for improved vision field
What are the 7 steps of synaptic transmission -brief version, please see notes for further detail
1) dendrite picks up the NT and sends an action potential to the terminal button
2) Once AP has arrived, it needs to be transferred by another neurone- it must pass the synaptic gap
3) At the end of the terminal buttons are synaptic vesicles
4) The synaptic vesicles release the NT that can then cross the synaptic gap
5) As NT diffuses across the synaptic gap, it binds to specialised receptors on the surface of the next cell, that recognise it and match that particular cell
6) Once next cell is activated an excitatory or inhibitory effect is produced
7) Synaptic transmission is repeated by a process called re-uptake
What are the first 3 steps of synaptic transmission-brief
1) dendrite picks up the NT and sends an action potential to the terminal button
2) Once AP has arrived, it needs to be transferred by another neurone- it must pass the synaptic gap
3) At the end of the terminal buttons are synaptic vesicles
What are the last 4 steps of synaptic transmission -brief
4) The synaptic vesicles release the NT that can then cross the synaptic gap
5) As NT diffuses across the synaptic gap, it binds to specialised receptors on the surface of the next cell, that recognise it and match that particular cell
6) Once next cell is activated an excitatory or inhibitory effect is produced
7) Synaptic transmission is repeated by a process called re-uptake
