biopsychology Flashcards
what is the function of the nervous system
- collect, process, respond to information in the environment
- to coordinate the working of different organs and cells in the body
what are the 2 divisions of the nervous system
peripheral nervous system (PNS)
central nervous system (CNS)
what is the function of the peripheral nervous system (PNS)
transmits messages to/from the CNS via neurons
what are the 2 divisions of the peripheral nervous system
autonomic nervous system (ANS)
somatic nervous system (SNS)
list 5 functions the autonomic nervous system (ANS) govern
- breathing
- heart rate
- digestion
- stress
- sexual arousal
what are the 2 divisions of the autonomic nervous system (ANS)
parasympathetic nervous system
sympathetic nervous system
what is the function of the parasympathetic nervous system
“rest and digest”
normal state
what is the function of the sympathetic nervous system
“fight or flight”
responds in times of stress
increased heartrate
increased blood pressure
list 2 things the “fight or flight” response causes
increased heartrate
increased blood pressure
finish this sentence :
the parasympathetic nervous system and the sympathetic nervous system work in ………. to each other
the parasympathetic nervous system and the sympathetic nervous system work in OPPOSITION to each other
what is the function of the somatic nervous system (SNS)
governs muscle movement
receives information from sensory receptors
name the 2 main components of the central nervous system
- brain
- spinal cord
what is the outer layer of the brain called
cerebral cortex
how many hemispheres does the brain have
2
what is the function of the brain
centre of concious awareness
what is the function of the spinal cord ( 3 marks)
passes messages to/from brain
connects nerves to the PNS
controls reflex action
describe 3 changes that occur during the sympathetic state
- increased heartrate
- increased breathing rate
- pupils dilate
what is the function of the endocrine system
instructs glands to release hormones into the bloodstream
what hormone does the thyroid gland release
thyroxine
what is the function of thyroxine
increase heartrate and metabolic rate (which affects growth)
what hormone do the adrenal glands release
adrenaline
what is the function of adrenaline
creates the physiological arousal needed for the fight or flight response
where is the adrenal gland located
ontop of kidneys
where is the thyroid gland located
throat
where is the pituitary gland located
in the brain
what is the function of the pitutiary gland
“master gland”
controls the release of hormones from other glands in the body
define neuron
nerve cells that process and transmit messages through electrical and chemical signals
how many neurons are in the body
100 billion
what percentage of neurons are located in the brain
80%
name the 8 parts to the structure of a neuron
dendrite
nucleus
cell body (soma)
myelin sheath
node of ranvier
axon
axon terminal
terminal button
what is the function of dendrites
carry nerve impulses from other neurons towards the body cell
what is the function of a nucleus
contains the genetic material of a cell
what is the function of the myelin sheath
fatty layer that protects the axon
and speeds up the electrical transmission of impulses
what is the function of the node of ranvier
gaps which speed up trasnmission by forcing the impulse to jump across the gaps along the axon
what is the function of the axon
carry impulses away from the cell body down the length of the neuron
what is the function of terminal button
communicate with the next neuron in the chain
what is the function of sensory neurons
carry messages from the peripheral nervous system (PNS) to the central nervous system (CNS)
what is the
1. dendrite length
2. axon length
for sensory neuron
- long dendrites
- short axon
what is the function of relay neurons
connect sensory neurons to motor neurons or other relay neurons
what is the
1. dendrite length
2. axon length
for relay neurons
- short dendrites
- short axon
what is the function of motor neurons
connects the central nervous system to effectors (eg: muscles and glands)
name 2 types of effectors
muscles
glands
what is the
1. dendrite length
2. axon length
for motor neuron
- short dendrites
- long axon
fill in the gaps using the word list
The knee- jerk reflex is an example of a reflex arc
A stimulus (e,g: hammer) hits the knee. This is detected by sense organs in the … which convey a message along the ……. ……
This message reaches the … , where it connects with a ….. ……
This transfers the message to a ….. ……
This carries a message to an …….. which causes the muscle to contract causing the knee to jerk
MISSING WORDS:
EFFECTOR
SENSORY NEURON
MOTOR NEURON
CNS (CENTRAL NERVOUS SYSTEM)
PNS (PERIPHERAL NERVOUS SYSTEM)
RELAY NEURON
The knee- jerk reflex is an example of a reflex arc
A stimulus (e,g: hammer) hits the knee. This is detected by sense organs in the PNS which convey a message along the SENSORY NEURON
This message reaches the CNS , where it connects with a RELAY NEURON
This transfers the message to a MOTOR NEURON
This carries a message to an EFFECTOR which causes the muscle to contract causing the knee to jerk
define action potential
neuron is activated by stimulus
neuron fires and creates an electrical impulse
define synapse
gap between neurons that signals are chemically transmitted across
define neurotransmitters
chemicals that diffuse across a synapse to the next neuron in the chain
what happens once a neurotransmitter chemically diffuses to the next neuron
it is converted back into an electrical impulse
why is neurotransmitters having a specific shape important
neurotransmitters have a specific shape that perfectly fits with the postsynaptic receptor site
this allows it to have a specific function
define summation
action potential of postsynaptic neuron is only triggered if the sum of the excitatory and inhibitory signal at any 1 time reaches the threshold
define excitation
neuron becomes more positively charged
therefore more likely to fire
define inhibitory
neuron becomes more negatively charged
less likely to fire
