NERVOUS SYSTEM:Divisions and The Brain Flashcards
What is the nervous system made up of?
neurons not organs
2 nervous system groups
Central nervous system:brain and spinal
Peripheral nervous system:CNS to body parts
Parts of the CNS
brain and spinal cord
parts of the PNS
somatic (voluntary)
autonomic (involuntary)
What does the PNS do?
Connects CNS to rest of body
12 cranial nerves take impulses to and from the brain
31 spinal nerves that take impulses to and from spinal cord
contains only nerves
What is the somatic nervous system
nerve controlling -voluntary musculoskeletal region -exterior sense organs -reflex arcs ALL UNDER VOLUNTARY CONTROL
What is the autonomic nervous system
-made up of smooth muscle, cardiac muscle and glands
-motor neurons that control internal organs
INVOLUNTARY CONTROL(happen automatically)
What is the sympathetic nervous system
Falls under autonomic category
- flight or fight (preparing for action)
- simultaneous release of noradrenaline from sympathetic neurons (and adrenalin)
What does noradrenaline and adrenalin do? (sympathetic NS)
1.Increase heart rate and BP
2.Widens airway
3.Contracts muscle
4.pupils dilate
5.blood flow to skeletal muscles increase
6.digestive activity decrease
PREPARES BODY FOR ACTION
What does the parasympathetic nervous system do?
involved in relaxation (rest and digest)
releases acetylcholine to return body to normal state after stress
What does acetylcholine do? (parasympathetic NS)
(opposite of adrenaline)
- decrease heart rate and BP
- contracts airway
- releases muscles
- iris widens
- decrease of blood flow
- increased digestion
What does the Central nervous system do?
composed of brain and spinal cord
-enclosed in 3 layers of membranes and bone
cerebrospinal fluid and tissue insulate brain and spinal cord
parts of the spinal cord?
Cervical-neck
Thoracic
Lumbar-abdominal
Sacral-tail bone
brain regions
Hindbrain
midbrain
forebrain
What is the hindbrain composed of/what is it for?
Midbrain
Medulla oblongata
Pons
Primitive, oldest part of brain (brain stem)
What does the MEDULLA OBLONGATA do?
HINDBRAIN
unconscious part of brain
close to spinal cord
regulates heartbeat, breathing, BP
reflex centres
what does the PONS do? (HINDBRAIN)
carries on activities from MO
What does the MIDBRAIN do? (HINDBRAIN)
connects hindbrain and forebrain
contains reflex centre for vision, hearing and touch
What is the cerebellum?
butterfly shaped, near brain stem
Impulses for movements controlled here
coordinates small muscle movements
maintains muscle control and coordinates balance
What does the cerebrum do? (FOREBRAIN)
wrinkled for surface area
MAINLY WHITE MATTER
divides into right and left hemispheres
-connected by corpus callosum
-coordinates sensory data and voluntary motor functions
-memory stored and voluntary processes
GOVERNS INTELLIGENCE AND REASONING, PLANNING LEARNING, MEMORY, AND PERSONALITY
What does the left side of the cerebrum do? Right?
left-verbal
right-visual
What are the hemispheres of the cerebrum covered in?
cerebral cortex for intelligence
How is this cerebrum divided?
into 4 lobes
- occipital
- temporal
- parietal
- frontal
What does the occipital lobe do?
receives and processes visual info
