The Nervous System

Question 1

Central Nervous System (CNS)

Answer 1

Brain
Spinal cord
Cranium protects brain
Vertebrae protects spinal cord

Question 2

Peripheral Nervous System

Answer 2

Nervous system (except brain + spinal cord)
Divided into - sensory division
-visceral sensory division
-somatic sensory division
- motor division
-visceral motor division
-somatic motor division

Question 3

Sensory division

Answer 3

Carries signals FROM receptors TO the CNS

Question 4

Motor divisions

Answer 4

Carries signal FROM CNS TO glands and muscles

Question 5

Visceral sensory division

Answer 5

Carries signal FROM
- viscera of the thoracic
- abdominal cavities
TO CNS

Question 6

Somatic sensory division

Answer 6

Carries signals FROM
                             - Skin
                             - Muscle
                             - Bone
                             - Joint receptors 
TO CNS

Question 7

Visceral Motor division

Answer 7

Carries signals TO

                      - glands
                      - cardiac muscles
                      - smooth muscles involuntarily

Question 8

Somatic motor division

Answer 8

Carries signals TO

                       - Skeletal muscles
                       - Produce muscular contractions

Question 9

Visceral motor division two other divisions

Answer 9

Parasympathetic Divisions

Sympathetic Divisions

Question 10

Parasympathetic divisions of visceral motor division

Answer 10

Co-ordinates more relaxed actions e.g digestion

Question 11

Sympathetic divisions of visceral motor division

Answer 11

Arouse the body

- co-ordinates the bodys response to stress

Question 12

Neuron

Answer 12

Nerve cells, the functional unit of the Nervous System
Send and receive info all over the body through:
-chemical signals
-electrical signals

Question 13

Dendrites

Answer 13

Appendages, receive signals

More dendrites = More info

Question 14

Axon

Answer 14

Conducts + transmits info

• Signals move away from cells
• 1 axon per nerve cells
• coated with myelin sheath by myelinating schwann cells

Question 15

Myelin sheath

Answer 15

A fatty substance made of glial cells

- Allows nerve impulses to travel quickly

Question 16

Classes of neurons

Answer 16

Sensory neurons
Interneurons
Motor Efferent neurons

Question 17

Sensory neurons

Answer 17

Detect stimuli

Send info to CNS

Question 18

Interneurons

Answer 18

Integrate signals from other neurons

Interconnect incoming sensory signals + outgoing motor pathway

Question 19

Motor Efferent neurons

Answer 19

Send signals to muscles + glands to respond to stimuli

Question 20

Neuroglia

Answer 20

Supportive cells in the nervous system

- fibre-like extensions stem from cells

Question 21

Synapses

Answer 21

Meeting point between neuron + other cells
Make neural integration that determine wether a second cell will respond to the signals
1 neuron = multiple synapses

Question 22

Presynaptic neuron

Answer 22

Neuron before synapse

Question 23

Postsynaptic neurons

Answer 23

Neuron after the synapse

Question 24

3 major portions of the brain

Answer 24

Cerebrum
Cerebellum
Brainstem

Question 25

Cerebrum

Answer 25

Largest part of the brain Consists of 2 cerebral hemisphere Hemisphere divided by longitudinal fissure (deep groove)

Question 26

Cerebellum

Answer 26

Beneath the cerebrum

Question 27

Brainstem 3 structures and what it consists of

Answer 27

``` Consists of: Diencephalon Midbrain Pons Medulla oblongata ``` 3 structures Thalamus Hypothalamus Epithalamus

Question 28

Brain stem

Answer 28

``` Ends at foramen magnum of the skull CNS continues afterwards to the spinal cord Composed of: Gray matter -forms surface cortex White matter -lies deep inside cortex Made of myelinar nerve tracts ```

Question 29

The Three Meninges

Answer 29

``` Three connective tissue membrane Dura mater Arachnoid mater Pia mater Subarachnoid space between each layer ```

Question 30

4 Internal Chambers

Answer 30

``` 2 lateral ventricles - in cerebral hemisphere 3rd between hemispheres 4th between pons + cerebellum Have choroid plexus to produce |cerebrospinal fluid| ```

Question 31

Direction of cerebrospinal fluid in brain

Answer 31

Lateral ventricles 3rd ventricle + 4th ventricle Subarachnoid space Blood

Question 32

Cerebrospinal fluid functions

Answer 32

``` Buoyancy -floats brain -> neutrally buoyant Protection -cushions skull impact Chemical stability -rinses waste ```

Question 33

Lobes of cerebrum

Answer 33

``` Frontal lobes Parietal lobe Occipital lobe Temporal lobe Limbic lobe ```

Question 34

Frontal lobe

Answer 34

``` Forehead to central sulcus Mental process Cognition Speech Motor control ```

Question 35

Precentral gyrus

Answer 35

Primary motor centre in frontal lobe | Controls muscles + joint movements of contralateral side for motor execution

Question 36

Parietal lobe

Answer 36

Located at central sulcus + extends caudally | -receive + interpret signals of taste + sense

Question 37

Postcentral gyrus

Answer 37

Primary somatosensory centre in parietal lobe Provides sensation Interprets pain and temperature

Question 38

Occipital lobe

Answer 38

Located at the rear of the brain | - visual centre

Question 39

Temporal lobe

Answer 39

Separate from parietal lobe by lateral sulcus - Hearing - Smell - Learning - Memory - Some aspect of vision + emotion

Question 40

Cerebellum

Answer 40

``` Largest part of the hindbrain Receives most signals from pons Responsible for: -motor co-ordination -equilibrium -memory of motor skills ```

Question 41

Diencephalon

Answer 41

Mainly composed of the Thalamus Hypothalamus

Question 42

Thalamus

Answer 42

Relay + process most of sensory signals

Question 43

Hypothalamus

Answer 43

Inferior to thalamus Controls emotions Autonomic functions Hormone production

Question 44

Midbrain

Answer 44

``` Conducts signals up + down brainstem Interconnects with cerebellum Centres for: - vision - hearing - motor control - maintenance of consciousness ```

Question 45

Pons

Answer 45

``` Rostral to medulla Conducts signals to brain stem Interconnects with cerebellum Centre for: - subconscious somatic motor sensor - visceral motor sensor ```

Question 46

Medulla oblongata

Answer 46

``` Most caudal part of the brain Inside foramen magnum - Conducts signals up + down brainstem - Interconnects with cerebellum Autonomic centre for: - Regulation of visceral functions ```

Question 47

Spinal cord

Answer 47

Conducts signals up + down the body Controls locomotion Mediates reflexes

Question 48

4 regions of spinal cord

Answer 48

``` Cervical |8 | Thoracic |12| Lumbar |5 | Sacral |5 | (Coccyx) |1 | 31 pairs of spinal nerves Occupies vertebral canal ```

Question 49

Cervical enlargement

Answer 49

Nerves of upper limbs

Question 50

Lumbar enlargement

Answer 50

Nerves of pelvic region + lower limbs

Question 51

Cauda equina

Answer 51

Bundle of roots, occupies canal from L2-S5 | Innervate pelvic organs + lower limbs

Question 52

Meninges in vertebrae

Answer 52

``` (Epidural space) Dura mater Arachnoid mater (Subarachnoid space) Pia mater ```

Question 53

Gray matter in vertebrae

Answer 53

``` Makes 'H' shape Contains: -soma -dendrites -synapses Integrate info Initiate commands ```

Question 54

Dorsel/ posterior horn (Gray matter)

Answer 54

Receives sesnory nerve fibres

Question 55

Ventral/anterior horn (Gray matter)

Answer 55

Contains soma | Give rise to efferent nerve fibres

Question 56

Lateral gray horn

Answer 56

Contians somas of sympathetic neurons

Question 57

White matter

Answer 57

``` Surrounds gray matter Divided by - posterior column - lateral column - anterior column Each column consists of bundles of nerve fibres Carry info from place to place ```

Question 58

Tracts definition

Answer 58

Bundle of axins in CNS