nervous system and the five senses Flashcards
what are the two branches of nervous system?
Central nervous system and peripheral nervous system
what is the function of CNS?
to integrate and respond to signals from PNS
what are the two components of CNS?
Brain and spinal cord
what is the function of PNS?
keep in touch with outside environment and respond to it
what is PNS comprised of?
nerves outside of brain and spinal cord; motor and sensory neurons
what is the autonomic nervous system?
part of PNS; responds to stimuli over which we dont have control over.
what are the two branches of autonomic
sympathetic and parasympathetic
what is sympathetic branch?
fight or flight response; response to perceived threats
what does the sympathetic branch secrete
adrenaline(epinephrine)
what is a neuron(neurone)
a specialized nerve cell;
- it doesnt undergo mitosis after birth, cannot be replaced
- conducts action potentials
what are action potentials
change in electrical potential with passage of an impulse along the membrane of a muscle cell or nerve cell
what is synapse
small gap b/w ends of nerves
how do nerve impulses continue when it reaches a synapse?
neurotransmitters
what are neurotransmitters
they transmit nerve impulses across synapses
what are an example of the 5 neurotransmitters
acetylcholine serotonin dopamine adrenaline endorphins
when does the impulse for release of neurotransmitters occur?
at the axon end
4 stages of action potentials?
- resting potential
- depolarization
- repolarization
- resting potential
what is a nerve?
is a cord made up of bundles of axons, it comprises white matter
what is white matter
nerve cords
what is grey matter
bodies of nerve cells
where is grey matter mainly found?
in the brain and spinal cord, but also in ganglia and some organs.
what is somatic nervous system branch?
controls voluntary movements
motor neurons
CNS to muscles and glands
sensory neurons
sensory organs to CNS
what is cerebrum?
cerebrum is the centre of intellegence, morality and problem-solving in the brain
what are the 4 lobar divisons of cerebrum?
frontal
parietal
temporal
occipital
what does frontal lobe of cerebrum do?
intellect, movement, speech, sexual behaviour, aggression
what does parietal lobe of cerebrum do?
communication, touch, taste, body imaging, abstract reasoning
what does temporal lobe of cerebrum do?
smell, memory centre, hearing, language, emotions
what does occipital lobe of cerebrum do?
sight
what is the function of brainstem?
relay messages b/w body and components of the brain
what are the three components of brainstem?
upper brainstem= midbrain
middle brainstem=Pons varoli
lower brainstem=medulla oblongata
what is the function of midbrain?
to relay nerve impulses from cerebrum to cerebellum and spinal cord
-and assist in balance
what midbrain made up of?
white matter(nerve cords)
what is the function of Pons Varoli?
- pons functions to connect hemispheres of cerebellum
- relay impulses, especially for cranial nerves
what is pons made up of?
grey and white matter with opposite configuration to cerebrum
3 functions of cerebrum
- cognitive activity
- sensory perception
- voluntary movement
what is the function of medulla oblongata
- relay for sensory nerves
- centre for certain autonomic body functions
what are the specific autonomic functions of medulla oblongata?
- cardiac
- respiratory
- vasomotor(bp)
- activities like coughing, sneezing, vomitting, swallowing.
what is the function of cerebellum
to assist in muscle coordination
maintain muscle tone
maintain balance
maintain awareness
how is cerebellum connected to the brain?
by penducles
superior=connects to midbrain and cerebrum
middle=connects to pons
lower=connects to medulla and spinal cord
what is cerebellum made up of
outer grey matter and inner white matter, like cerebrum
-white is very branched
three organs that are non-cortical grey matter
- basal ganglia
- thalamus
- hypothalamus
what is the function of basal ganglia?
influence movement eye movement procedural learning/habits motivation decision making working memory/focus
what is the function of thalamus
pre-processes pain, temp, touch
-involved in self awareness and the senses
damage/dysfunction of thalamus can result in…
disruption to sleep, consciousness, sensation, and recall.
what is the function of hypothalamus
- controls the pituitary gland
- involved in emotions, behaviour, hunger/thirst, and influences the autonomic nervous system
disfunction/disruption of the hypothalamus can result in..
disruption can result in a wide variety of basic physiological functions.
what is the brain ‘housed in”
the brain is housed in the cranial
what is the spine “housed in”
spinal canal
what does the forebrain become
cerebrum
what does the midbrain become
midbrain
what does the hindbrain become
pons varoli
medulla oblongata
cerebellum
spinal cord
What is the Somatic NS comprised of?
Afferent sensory nerves and efferent motor nerves
What are the 3 cranial meninges?
- Dura mater (outer)
- Arachnoid mater (middle)
- Pia mater (inner)
Where is the cerebrospinal fluid found?
in sub-aracnoid space(In-between the the arachnoid mater and the Pia mater)
Which meninges is in touch with the skull bone?
dura mater
What does the brain control?
- Sensory awareness
- Movement
- Behaviour
- Rational thoughts
- Memory
etc. ..
Where is the grey matter found?
In the out areas; the cortex, mostly the bodies.
Where is the white matter found?
In the inner areas of the brain. Mostly the axons
What connects the two brain lobes together?
corpus collosum
What is the Cerebrum for?
The centre of intelligence, morality and problem solving
function of cerebrum
- Cognitive activity (to think)
- Sensory perception
- Voluntary movement
What is the function of the brainstem?
To relay messages between the body and the components of the brain. Its located at the top of the spinal cord.
What is the midbrain composed of?
white matter
What does damage to the cerebellum result in?
intoxication like symptoms
What is the function of the Falx cerebri?
Keeps hemispheres slightly apart in cerebrum.
What is the function of the Falx cerebelli?
A transverse separation of the cerebrum and cerebellum
Where is grey and white matter found in the spinal cord?
White matter is on the outside
Grey matter is on the inside
What is Cerebro-spinal fluid (CSF) comprised of?
Water, proteins, AAs, glucose and salts
What is CSF produced by?
Produced by the choroid plexuses (network of capillaries) in spaces of the brain called ventricles.
function of CSF
- Support the brain and spinal cord
- Maintain uniform pressure
- Shock absorber
- Prevent desiccation
- Flush metabolic waste products into bloodstream
what is an action potential
A wave of disruption in membrane potential that travels down axons (NOT electricity)
What is the threshold of an action potential?
-55 mV
What is the steps to action potentials?
1. Resting potential; more (-) inside (-70 mV) Na+/K+ pump 2. Depolarisation; goes positive Voltage-gated Na+ channel 3. Repolarisation; Tries to rebalance Voltage-gated K+ channel 4. Resting potential; back to normal Na+/K+ pump
What is the 1st/I cranial nerve?
Olfactory
What is the 2nd/II cranial nerve?
Optic
What is the 3rd/III cranial nerve?
Oculomotor
What is the 4th/IV cranial nerve?
trochlear
What is the 5th/V cranial nerve?
trigeminal
What is the 6th/VI cranial nerve?
Abducens
What is the 7th/VII cranial nerve?
facial
What is the 8th/VIII cranial nerve?
auditory
What is the 9th/IX cranial nerve
Glossopharyngeal
What is the 10th/X cranial nerve?
vagus
What is the 11th/XI cranial nerve?
Spinal accessory
What is the 12th/XII cranial nerve?
hypoglossal
What is a sentence to memorize the 12 cranial nerves?
“On Old Olympus’ Towering Top A Finn And German Viewed A Hop
acetylcholine is a…
neurotransmitter
part of the brain concerned with memory is…
cerebrum
CSF is found between which two layers?
aracnoid and pia mater
trigeminal nerve is what cranial nerve
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