Tech Nervous System Flashcards
Functions of the Nervous System
Name functons of the nervous system
- •Receive stimuli (sensory) from outside and inside the body which are then analysed and the appropriate response produced
- •Convey impulses (motor) from the brain which may stimulate or depress activity in muscular, glandular and other tissues
- •Integrate (unify) the many different functions carried out by individual organs, tissues and cells
System Organisation
Central Nervous System
consists of what
Brain & Spinal Cord
System Organisation
Peripheral Nervous System
consists of What
12 pairs of cranial nerves,
31 pairs of spinal nerves,
Autonomic nervous system
Draw diagram of the perpheral and Central nervous system
Draw diagram of the perpheral, Central nervous system and Autonomics
The Autonomic Nervous System
controls what ?
Sympathetic & Parasympathetic
Components of the PNS
Draw Diagram
Sympathetic & Parasympathetic
which reactions from each
Central Nervous System
Cerebrum
Contains and does What?
- 2 hemispheres
- 4 lobes
- Motor areas – initiate voluntary muscle contraction
- Sensory areas
- Special sense centres
- Centres of “higher mental powers”
- Thalamus & Hypothalamus
Cerebrum
•Each hemisphere is divided into 4 lobes
what are they
•Each hemisphere is divided into 4 lobes
Frontal
- Parietal
- Temporal
- Occipital
Cerebrum
Thalamus does what
•Thalamus – receives sensory impulses from the body and redistributes them to the cerebrum
•
Cerebrum
Hypothalamus does what?
•Hypothalamus – controls the autonomic n.s., appetite, thirst, body temperature, emotion.
Cerebellum
contains what?
does what?
- 2 hemispheres
- Grey matter on the surface
- White matter inside
- Coordinates voluntary muscle movement
- Maintenance of balance
- Proprioception
- Activities of cerebellum are involuntary
Brain Stem
Mid Brain
- Relay station
- Reflex centres
•
Pons
- Relay station
- Pneumotaxic centre
- Apneustic centre
Medulla Oblongata
- Below the pons
- Continuous with spinal cord below
- Vital centres
- Decussation of the pyramids
Reflex centres
Meninges
3 protective membranes
- Dura Mater
- Arachnoid Mater
- Pia Mater
Cerebrospinal Fluid
- Produced in 4 ventricles (cavities)
- •Circulates around the brain and cord
- •Secreted continuously – 720 ml per day
- •Remains constant at about 120 mls
CSF
Consists of:
Consists of:
- Water
- Mineral salts
- Glucose
- Plasma proteins
- Creatinine
- Urea
- leukocytes
CSF
Functions:
Functions:
- Lubricates brain and spinal cord•
- Supports the brain & cord, maintaining a uniform pressure
- Acts as a shock absorber
- Nourishes and cleans by removing toxic substances
Spinal Cord
- Extends from medulla to upper border of L2
- 45 cm long
- Approx thickness of little finger
- Protected by spinal column
- Links brain to rest of body
- Conveys sensory and motor nerve impulses
- Acts as centre of reflex action
Peripheral Nervous System
P.N.S
Made up of what
- 31 pairs of spinal nerves
- 12 pairs of cranial nerves
- The autonomic nervous system
- Sensory (afferent) nerves
- Motor (efferent) nerves
Mixed nerves
what are efferent and afferent nerves?
- Sensory (afferent) nerves
- Motor (efferent) nerves
Spinal Nerves
31 pairs of spinal nerves
- 8 cervical
- 12 thoracic
- 5 lumbar
- 5 sacral
- 1 coccygeal
Spinal Nerves
Spinal nerves leave the vertebra via
•Spinal nerves leave the vertebra via intervertebral foramen corresponding with their position on the spinal column
•
•This is with the exception of the 1st cervical pair which leaves between the occipital bone and atlas
Cranial Nerves
how many
do what
- 12 pairs
- Relay sensory information such as sight, taste, hearing and smell to specialised areas in the brain
- Relay information relating to touch, temperature and pain from the head and neck
- Control motor functions of muscles around the head and neck
- Autonomic control of many internal organs by the vagus nerve, the only cranial nerve to extend beyond the neck
Autonomic Nervous System
- Regulates activities of smooth muscle, cardiac muscle & glands
- Effects are rapid and essential for homeostasis
- Carries out activities automatically/involuntarily i.e. without conscious control
- Also known as visceral efferent system
- Function generally motor
Autonomic Nervous System
Sensory (afferent) neurons carry impulses from ?
efferent) neurons that convey impulses from CNS to ?
•Sensory (afferent) neurons carry impulses from viscera (organs)
•
•Motor (efferent) neurons that convey impulses from CNS to smooth muscle, cardiac muscle and glands
Autonomic Nervous System
Two divisions:
Two divisions:
•Sympathetic Nerves
(Thoracolumbar outflow)
•
•Parasympathetic Nerves
(Craniosacral outflow)
Sympathetic Nerves
(Thoracolumbar outflow) other name
•Sympathetic Nerves
(Thoracolumbar outflow)
Autonomic Nervous System
(Craniosacral outflow)
Parasympathetic Nerves
Homostasis is a dynamic balance between Autonomic branches which are
•Sympathetic Nerves
(Thoracolumbar outflow)
•
•Parasympathetic Nerves
(Craniosacral outflow)
Sympathetic
- Predominates during stress
- “Fight or flight”
- Stimulates the heart, circulation & respiration
- Inhibits peristalsis
- Noradrenaline
Parasympathetic
- Predominates during rest
- “Rest and digest”
- Slows the heart, circulation and respiration
- Stimulates digestion
- Acetylcholine
Terminology
- Paraplegia
- Tetraplegia / Quadriplegia
- Hemiplegia
- Monoplegia
- Meningitis
Terminology
•Identify the sympathetic effects of the autonomic nervous system on the following structures:
a) Heart
b) Air passages (bronchioles)
c) Blood vessels
d) Organs of digestion (stomach and small intestine)
e) Eye
•Identify the parasympathetic effects of the autonomic nervous system on the following structures:
a) Heart
b) Air passages (bronchioles)
c) Blood vessels
d) Organs of digestion (stomach and small intestine)
e) Eye
•Identify 3 drugs available for use by an Ambulance Technician that have similar effects on the body to those of the Autonomic Nervous System
