17.2 quiz Flashcards
The CNS is the location of what
where sensory information is received and motor control is initiated.
The spinal cord and brain are protected by what
bone (vertebrae in cord and skull in brain)
Both spinal cord/brain are wrapped in protective membranes called _____
meninges
The spaces between the meninges are filled with what?
Cerebrospinal fluid.
What is the role of cerebrospinal fluid?
Cushions and protects the CNS.
How do you test for meningitis?
Sample cerebrospinal fluid through spinal tap/lumbar puncture
What are the two types of nervous tissues
Gray and white matter
What is gray matter made up of
Cell bodies and short, non-myelinated fibres
What is white matter made up of
myelinated axons that run together in bundles called tracts
What does the spinal cord pass through
The vertebral canal
How do spinal nerves project from the cord
They project between the vertebrae
What cushions and separates the vertebrae
Fluid-filled intervertebral disks
What is the spinal cord central canal filled with
cerebrospinal fluid, grey matter in an H-shape configuration inside white matter.
What does the white matter in the spinal canal contain
Tracts that take nerve impulses to and from the brain
What does the dorsal root contain
sensory fibres entering grey matter
What does the ventral root contain
motor fibres exiting grey matter
Where are the dorsal and ventral roots located
dorsal is at the top of each vertebrae and ventral is at the bottom
What are the four major parts of the brain
Cerebrum, diencephalon, cerebellum, brain stem
What is the largest part of the brain
Cerebrum
What is the role of the cerebrum
Communicates with and coordinates activities to other parts of the brain
What are the two halves of the cerebrum called and what do they communicate through
Cerebral hemispheres, the corpus callosum
What is the corpus callosum
a bridge of nerve tracts in the cerebrum that allow the left side of the brain to control right side of the body and vice versa
What is the cerebral cortex
the thin layer of grey matter that covers the cerebral hemispheres
What are the four lobes
frontal, parietal, occipital, temporal
What are the 4 lobes separated by
Grooves called sulci
What are the 4 roles of the frontal lobe
- Voluntary movement
- organizing motor functions
- reasoning and planning
- speech muscles
What are the 3 roles of the parietal lobe
- Somatic sensing (sensing within the body)
- Taste
- temperature
- touch/movement
What are the 3 roles of the temporal lobe
- Hearing
- Associates new audio info w previous audio info
- Understands written and spoken words
What are the 2 roles of the occipital lobe
- vision
- associates new visual info with previous visual info
What is the role of the central white matter in the brain
tracts take info between different areas
What is the role of basal nuclei in the cerebrum
masses of grey matter in the white matter that integrate motor commands to proper muscle groups
The Diencephalon consists of 3 parts
Hypothalamus, thalamus and pineal gland
What is the role of the hypothalamus
maintains homeostasis, regulates sleep, hunger, thirst, body temperature, water balance
What is the role of the thalamus
Grey matter that receives all sensory input except for smell, and sends to appropriate area of cerebrum, involved in memory and emotions
What is the role of the pineal gland
Secretes melatonin and maintains the normal sleep-wake cycle
The cerebellum is located where
Under the occipital lone
What is the structure of the cerebellum
Two portions that are composed of white matter with a thin layer of gray matter overtop
What is the role of the cerebellum
- Maintains posture and balance
- receives sensory input from joints/muscles
- Motor input about where body parts should be located
- produces smooth, voluntary movements
What does the brain stem contain
the midbrain, the pons, the medulla oblongata, and the reticular activating system
What is the role of the midbrain
relay station for tracts passing between cerebrum and spinal cord/cerebellum, reflex centres for visual/auditory/tactile responses
What is the role of the pons
Bundles of axons between cerebellum and CNS, regulates breathing rate with medulla oblongata
What is the role of the medulla oblongata
Regulates heartbeat/breathing/blood pressure and reflex centres for vomiting, coughing, sneezing, hiccuping, swallowing
What is the role of the RAS
Relay centre for alertness, filters out unnecessary stimuli
What are nerves
Specialized cells that carry impulse messages from one part of the body to another
What is a neuron
A nerve cell that characteristically has three parts: dendrite, cell body, axon
What are ganglia made of
Cluster of neural bodies outside central nervous system
What are cranial nerves
Nerves that serve primarily the head and neck
How many cranial nerve pairs are there
12
What is the function of spinal nerves
Mixed nerves with motor/spinal/autonomic signals between CNS and body
How many pairs of spinal nerves are there
31, one on each side of vertebrae column
What is the somatic system
Part of PNS that serves the skin, skeletal muscles and tendons
What is a reflex arc
The simple neural pathway that a reflexive (involuntary) action requires.
What are the sequences of a reflex arc
- stimulus
- Sensory receptors in skin send sensory impulses through dorsal root ganglia to spinal cord
- Sensory neurons that enter the cord dorsally pass signals on to many interneurons.
- Interneuron impulses synapse with motor neurons, where the impulse is taken to effector muscles
- response is brought (withdraw hand, etc.)
How many nerve pairs are in the somatic system
cranial (12), spinal (31), association (thousands)
Where do the voluntary movements of the somatic system originate?
cerebral cortex
What is the autonomic system of the PNS
The system responsible for the activity of the cardiac/smooth muscle and glands.
What are the two divisions of the autonomic system
The sympathetic and parasympathetic division
The autonomic system uses what for each impulse
two neurons that synpase at a ganglion
What is the sympathetic division of the autonomic system responsible for
fight/flight response
What are some examples of the fight or flight response in the sympathetic system
- inhibits tears
- increases heartbeat
- stimulates liver to release glucose for energy
What is the parasympathetic division of the autonomic system responsible for?
Rest and digest (housekeeper)
What are some of the housekeeper roles of the parasympathetic system
- stimulates tears
- deceases heartbeat
- stimulates liver to release bile
Is the preganglionic and postganglionic fibre of the sympathetic division long or short
preganglionic is short, postganglionic is long
Is the preganglionic and postganglionic fibre of the parasympathetic division long or short
preganglionic is long, postganglionic is short
What is the parasympathetic division sometimes called
the cranioscacral portion, because it arises from the cranio and sacral portions of the spinal cord
Where does the sympathetic preganglionic fibre arise from
Arise from cervical, thoracic, lumbar parts of spinal cord
