skull and nervous system Flashcards
what are the two cell types within the nervous system tissue
- neurons
- neuroglia
major components of the nervous system
- brain
- spinal cord
- cranial nerves
- spinal nerves
- ganglia
- sensory receptors (internal and external)
what are the two major anatomical divisions of the nervous system
- central nervous system (CNS)
- peripheral nervous system (PNS)
central nervous sytem
brain and spinal cord
peripheral nervous system (PNS)
- cranial nerves and spinal nerves
- ganglia and sensory receptors
nerve
bundle of axons (nerve cell fibers) located outside the brain and spinal cord
cranial nerves
- 12 pairs of nerves
- emerge from the base of the brain
spinal nerves
- 31 pairs of nerves
- emerge from the spinal cord
ganglia
- cluster of neuron cell bodies
- located outside the CNS
sensory receptors
- monitor changes in environment
- skin, eyes, nose, muscles
functional organization of the nervous system
- sensory function (input)
- integrative function (control)
- motor function (output)
sensory function
input
- sensory receptors detect internal and external stimuli
- sensory (afferent) neurons transmit information to CNS
integrative function
control
- interneurons (located in the CNS) analyze sensory information
- perception (conscious awareness) of stimuli
motor function
output
- motor (efferent) neurons respond to integration
- initiate action in effector organs (muscles, glands)
divisions of nervous system
CNS:
- brain
- spinal cord
PNS:
- somatic nervous system
- autonomic nervous system
autonomic nervous system:
- sympathetic nervous system
- parasympathetic nervous system
somatic nervous system
regulates VOLUNTARY control of skeletal muscles
somatic sensory neurons
- convey information to the CNS from sensory receptors
- input of information to the CNS for integration
somatic motor neurons
- convey information from the CNS to SKELETAL MUSCLE
- output of information from the CNS for muscular contraction
autonomic nervous system
involuntary actions
“automatic actions”
sympathetic nervous system (SNS)
- fight or flight
- increase in activity and metabolic rate
ex. dilate pupils, increase heartrate, inhibit intestinal activity
parasympathetic nervous system (PNS)
- rest or digest
- decrease activity in metabolic rate
ex. constrict pupils, decrease heartrate, stimulate intestinal activity
neurons
basic structural and functional units of the nervous system
- transfer and processing of information
neuroglia
smaller and more abundant
- support, nourish, protect neurons
(do not transfer information)
cerebrum
telencephalon
- largest and most anterior part of the brain
- front of skull
- 2 hemispheres
- read, write, speak, calculations, memories, planning
cerebrum: structure
- cerebral hemisphere
- white matter
- gray matter
- gyrus
- sulcus
cerebral cortex
- outer layer
- covers cerebrum
cerebrum features
longitudinal fissure
corpus callosum
longitudinal fissure
separates right and left cerebral hemispheres
corpus callosum
connects right and left cerebral hemispheres
- composed of white matter
- how the 2 sides communicate
cerebrum lobes
- frontal lobe
- temporal lobe
- parietal lobe
- occipital lobe
- insular lobe
frontal lobe
- integration of decision making
- planning
- mood
- behaviour
temporal lobe
- hearing processes
- specking
- hearing + responding
parietal lobe
- responding to stimuli from the environment
occipital lobe
vision
insular lobe (insula)
- more automatic responses take place (NOT ALL)
lobe divison
lateral sulcus
- frontal and temporal
central sulcus
- frontal and parietal
parieto-occipital sulcus
- parietal and occipital
cerebellum features
folia
- gray matter
arbor vitae
- white matter
what does the cerebellum do
coordinate voluntary movements
regulates posture and balance
cerebellum structure
- cerebellar peduncles
- cerebellar hemispheres
- vermis (connects between 2 hemispheres)
axial skeleton
- bones of skull
- accessory bones
- vertebral column
- thoracic cage
appendicular skeleton
- upper limbs and pectoral girdle
- lower limbs and pelvic girdle
neurocranium (braincase)
TOTAL= 8 bones
- frontal (1)
- parietal (2)
- occipital (1)
- temporal (2)
- ethmoid (1)
- sphenoid (1)
viscerocranium (facial skeleton)
TOTAL= 14 bones
- maxillae (2)
- palatine bones (2)
- nasal bones (2)
- inf. nasal conch (2)
- zygomatic bones (2)
- lacrimal bones (2)
- vomer (1)
- mandible (1)
what is the skull total bones
22
neurocranium function
- surrounds and protects the brain
- articulates with the vertebral column
viscerocranium function
supports and protects entrances to the digestive and respiratory tracts
accessory bones functions
7 bones (hearing and muscles attachment)
external features of the temporal bone
- external acoustic meatus
- mastoid process
- styloid process
- zygomatic process
inferior view of neurocranium
- sphenoid bone
- temporal bone
- zygomatic process
- styloid process
- mastoid process
- mandibular fossa
- occipital bone
features of the occipital bone
- formen magnum
- occipital condyle
function of foramen magnum
passage of the spinal cord
function of occipital condyle
articulation with the atlas (C1)
ethmoid bone
- unpaired bone
- forms part of the: orbital wall, nasal cavity, septum
what bones form the orbit
- palatine zygomatic
- sphenoid
- maxilla
- ethmoid
- frontal
- lacrimal
features of the ethmoid bone
crista galli
superior nasal concha
middle nasal concha
inferior nasal concha (separate bone)
cribriform plate
branches of CN I (olfactory nerves passing through cribiform plate of ethmoid bone)
crista galli
perpendicular projection of the ethmoid bone
- acts as an anchoring point for membranes surrounding the brain (meninges)
feature of the sphenoid bone
unpaired bone
forms part of the eye orbit and the base of the skull
- sella turcica
- greater wing
- lesser wing (more superior)
- pterygoid processes
what does the sella turcica hold
pituitary gland
skull foramina
- many bones of the skulls have associated foramina
allow for passage of nerves and blood vessels
skull foramina: sphenoid bone
- inferior orbital fissure
- optic canal
- superior orbital fissure
- foramen spinosum
- foramen rotundum: CN V2
- foramen ovale: CN V3
- foramen lacerum
skull foramina: temporal bone
carotid canal
internal acoustic meatus
what passes threw the carotid canal
internal carotid artery
what passes threw internal acoustic meatus
CN VIII
sutures
boundaries between skull bones
- fibrous, immovable joints
the types of sutures
sagittal
coronal
squamous
lambdoid
sagittal suture
between parietal bones
coronal suture
frontal and parietal
lambdoid
occipital and parietal
squamous suture
temporal and parietal
cranial fossae
floor of the cranial cavity divided into 3 fossae
what are the 3 cranial fossa
anterior cranial fossa
middle
posterior
anterior cranial fossa
frontal lobe of the brain
- fronal, ehtmoid, sphenoid bones
middle cranial fossa
temporal lobes of brain
- sphenoid, temporal bones
posterior cranial fossa
cerebellum
- occipital, temporal bones
facial skeletion (lateral view)
- zygomatic
- maxilla
- mandible
- nasal
- lacrimal
temporomandibular joint (TMJ)
only moveable joint of the skull
articulation between:
- condylar process
- mandibular fossa
features of the mandible
- ramus
- body
- angle
- condylar process
- coronoid process
facial skeleton (inferior view)
- zygomatic bones
- zygomatic arch
- maxillae
- incisive foramen
- palatine bones
- vomer
hard plate
palatine process
palatine bones
