intro to nervous system Flashcards
the nervous system is composed of —— and it consists of 2 systems:
1—- which includes:
2- —- which includes:
- brain , spinal cord , prepherial nerves
- central nervous system which includes brain and spinal cord
- prepherial nervous system which includes cranial nerves ( 12 pairs ) and spinal nerves ( 31 pairs usually )
nerves cells are known as —- and they function to transmit — to other nerve cells , muscles, or gland cell which is basic working unit of brain.
this nerve cell consist of:
- neuron
- info
- consist of:
1- cytoplasm
2- nucleas
3- cell body ( soma )
4- axons
5- dendrite
the 3 types of neurons are:
1- —- which is sensory neuron in PSN
2- — receptor-axon-cell body-axon CNS eg. —–
3- —- which is found throughout the CNS , as multiple —- and a single —- eg.
1- pseudunipolar ( pseudo = false , uni = one )
2- bipolar eg. . peripheral sensory neurons for olfaction (smell), vision, hearing & balance
3- mutlipolar , multiple dendrite and a single exon as motor neurons
( check structure plsss)
—– provide structural support and myelin
supporting cells
brain and spinal cord:
1- glial cells:
—- produces myelin
—- for structural support eg. insulates synapse , uptake and synthesis of neurotransmitters
glial cells brain tumours are known as —-
2- —- specilized macrophages that remove damaged neurones and infection
3- —– are cells from epithelial lining of the ventricles in the brain and central canal of the spinal cord from the secretory epithelium ( choroid plexus ) that produces the cerborpsinal fluid
-Oligodendrocytes
- astrocytes
- gliomas
- microglia
- epidermal cells
the nerves in PNS are — which produce
Schwann cells produce myelin
( check slide 7 for structure )
in CNS:
1- Brain within —
2- spinal cord within —-
- the brain is — with the spinal cord at the —- which is a hole in base of skull through which the spinal cord passes
- cranium
- vertebral canal of the vertebral column
- continuous
- foramen magum
-meninges is a —–
contains – layers surrounding ——- which are:
- its a sub-arachnoid spaces between —–
- connective tissue membrane
- 3 layers
- Brain and spinal cord
- dura mater , arachnoid , pia
- arachnid and Pia which is filled w cerebrospinal fluid and arteries
brain :
1- the —–: right and left cerebral hemisphere and consists of —- and is —–
2- brain stem consist of:
3- cerebellum :
- forebrain
- lobes
- thalamic strcuture
- midbrain , pons , medulla oblongata
- behind pons
( check structure slide 11 )
the through midline of right and left refers to —- view of the brain which consists of:
- sagittal
consists of:Cerebral hemisphere
1-Corpus collosum
2-Thalamic structures
-Thalamus
-Hypothalamus
3-Cerebellum
4-Brain stem
-Midbrain
-Pons
-Medulla
the brain when divided into front and back refers to —- view which consists of:
- coronal view
1-Grey ( where cell body is found ) & white matter ( usually formed from myelinated axons )
2-Ventricles ( CHECK SLIDE 13 FOR STRCUTRE IMPORTANT )
3-Cerebrum
4-Cerebellum
5-Brain stem
grey and white matter:
1- neural tissue consist of:
2- most axons are surrounded by – which is found in —-
consists of:
3- the cell bodies are found in —-
4- in the spinal cord the grey matter is —
- axons and cells bodies
- myelin in the white matter which consists of:
- all CNS axons , most PNS axons
- oligiodendroytes and Schwann cells
- myelin insulates which speeds conduction
- grey matter
- butterfly shaped
-the spinal cord is from — at the – of the – to —–
- its continuous w —-
- surrounded by —-
- functions:
- foreman magnum at the base of the skull to L1 vertebra
- medulla oblongata
-meninges, cerebrospinal fluid and bone - functions:
1-Reflex center for each spinal cord segment (e.g. spinal reflexes)
2-Conduction pathway for impulses going to and from the brain
( check structure slide 16 ,17,18)
the PNS is consists of: —– and — which is divided into —
1- somatic nervous system which deals w controlling skeletal muscle
2- autonomic nervous system which regulates glands , blood vessels and internal organs consist of:
- sympathetic nervous system: fight or flight
- parasympathetic nervous system: rest and digest
In PNS:
- a — should always mean a peripheral nerve as — and —
- consist of collection of —-
- has —-
- nerve fiber is known as —
- nerve
- cranial and spinal
- collection of axons
- connective tissue
- axons
( check structure 20 )
cranial nerves have – pairs from the brain which include :
I :
II:
III , IV , VI :
V :
VII :
VIII :
IX , X
XI :
XII
- 12 pairs
I smell
II vision
III, IV, VI eye movements
V facial and scalp sensation, mandibular movements
VII facial expression
VIII hearing, balance
IX, X swallowing, phonation
XI neck and head movements
XII tongue movements
spinal nerves have – pairs from the spinal cord consist of :
- 31 pairs
consist of:
1- 8 cervical (neck) - C1-8 for neck and upper limb
2- 12 thoracic - T1-12 for upper limb and thorax
3- 5 lumbar - L1-5 for abdomen and lower limb
4- 5 sacral - S1-5 for lower limb and perineum
-The urinary and anal sphincters, and the external genitalia, are supplied by S2-4 (sphincters and sex)
5-1 coccygeal
spinal nerves are connected to spinal cord by —-
1- sensory:
- is —
- enters — aspect of spinal cord
- cell body in —
- — cluster of neural cell bodies outside CNS
2- motor:
- are —
- exists — aspect of spinal cord
- cell body in —-
- dorsal and ventral root
- afferent
- posterior
- spinal( dorsal root )ganglion
- ganglion
- efferent
- anterior
- spinal cord of grey matter
- spinal nerves and plexuses:
1- spinal nerves exit —
2- may form — of nerves : - combine — from —-
- form new — w —–
example:
- spinal cord
- plexuses-network of nerves
- fibres from different levels
- new nerves w specific targets or destination
as: median nerve (brachial plexus) contains fibres from C5, C6, C7, C8 & T1
—–are of a skin supplied by one spinal nerve which may help identify —-
dermatomes , helps identify site of lesion
example:the dermatome of S1 is supplied by S1 nerve which arises from S1 segment of spinal nerve (Sural nerve)
—– are group of muscle that a single spinal nerve innervates
- myotomes as; L3: knee extension
-Simplest, quickest form of activity in the nervous system
-Automatic, involuntary response to a stimulus
are known as —-
these are — which includes
or they can be —-
the stages include:
-reflexes/ reflex arc
- monosynaptic as knee and ankle
- polysynaptic
- stages :
1-Receptor
2-Sensory neuron
3-Integration centre
4-Motor neuron
5-Effector
-direction of nerve impulses : sensory and motor:
1- sensory afferent impulses move —- CNV
2- motor efferent impulses move — CNV
-nature of perception: somatic sensory - autominc visceral sensory:
1- we are acutely aware of these; well localised (e.g. sharp pain, touch). Generally originate in body wall structures rather than internal organs is known as —-
2- : either imperceptible, only vaguely localisable, or only become perceptible in disease. From blood vessels and internal organs (viscera) is known as —
- types of action; voumatry motor and atomic visceral or involuntary motor:
1- —– control skeletal muscle over which we have voluntary control
2- —— control muscle over which we do not normally have voluntary control
- towards
- away
- somatic senstation
- visceral sensation
- voluntary motor impulses
- Visceral (involuntary) motor or autonomic
atomic nervous system effect in parasympathetic and sympthatic:
1- sympathetic:
-Alert, wary, increases heart rate & contractility, blood pressure rises
-Blood vessels to muscles dilate , ready for running away
-Pupil dilation ,for good distant vision
-bronchioles dialtion
- close sphincter
2- para:
-Decreases heart rate and contractility
-Relaxes the gut tube muscle
-Pupil constriction
-Bronchioles constriction
-Open sphincters
