The Nervous System Flashcards Preview

Human Biology Course > The Nervous System > Flashcards

Flashcards in The Nervous System Deck (58):
1

Central Nervous System (CNS)

Brain
Spinal cord
Cranium protects brain
Vertebrae protects spinal cord

2

Peripheral Nervous System

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

3

Sensory division

Carries signals FROM receptors TO the CNS

4

Motor divisions

Carries signal FROM CNS TO glands and muscles

5

Visceral sensory division

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

6

Somatic sensory division

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

7

Visceral Motor division

Carries signals TO
- glands
- cardiac muscles
- smooth muscles involuntarily

8

Somatic motor division

Carries signals TO
- Skeletal muscles
- Produce muscular contractions

9

Visceral motor division two other divisions

Parasympathetic Divisions
Sympathetic Divisions

10

Parasympathetic divisions of visceral motor division

Co-ordinates more relaxed actions e.g digestion

11

Sympathetic divisions of visceral motor division

Arouse the body
- co-ordinates the bodys response to stress

12

Neuron

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

13

Dendrites

Appendages, receive signals
More dendrites = More info

14

Axon

Conducts + transmits info
- Signals move away from cells
- 1 axon per nerve cells
- coated with myelin sheath by myelinating schwann cells

15

Myelin sheath

A fatty substance made of glial cells
- Allows nerve impulses to travel quickly

16

Classes of neurons

Sensory neurons
Interneurons
Motor Efferent neurons

17

Sensory neurons

Detect stimuli
Send info to CNS

18

Interneurons

Integrate signals from other neurons
Interconnect incoming sensory signals + outgoing motor pathway

19

Motor Efferent neurons

Send signals to muscles + glands to respond to stimuli

20

Neuroglia

Supportive cells in the nervous system
- fibre-like extensions stem from cells

21

Synapses

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

22

Presynaptic neuron

Neuron before synapse

23

Postsynaptic neurons

Neuron after the synapse

24

3 major portions of the brain

Cerebrum
Cerebellum
Brainstem

25

Cerebrum

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

26

Cerebellum

Beneath the cerebrum

27

Brainstem 3 structures and what it consists of

Consists of:
Diencephalon
Midbrain
Pons
Medulla oblongata

3 structures
Thalamus
Hypothalamus
Epithalamus

28

Brain stem

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

29

The Three Meninges

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

30

4 Internal Chambers

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

31

Direction of cerebrospinal fluid in brain

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

32

Cerebrospinal fluid functions

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

33

Lobes of cerebrum

Frontal lobes
Parietal lobe
Occipital lobe
Temporal lobe
Limbic lobe

34

Frontal lobe

Forehead to central sulcus
Mental process
Cognition
Speech
Motor control

35

Precentral gyrus

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

36

Parietal lobe

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

37

Postcentral gyrus

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

38

Occipital lobe

Located at the rear of the brain
- visual centre

39

Temporal lobe

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

40

Cerebellum

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

41

Diencephalon

Mainly composed of the
Thalamus
Hypothalamus

42

Thalamus

Relay + process most of sensory signals

43

Hypothalamus

Inferior to thalamus
Controls emotions
Autonomic functions
Hormone production

44

Midbrain

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

45

Pons

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

46

Medulla oblongata

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

47

Spinal cord

Conducts signals up + down the body
Controls locomotion
Mediates reflexes

48

4 regions of spinal cord

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

49

Cervical enlargement

Nerves of upper limbs

50

Lumbar enlargement

Nerves of pelvic region + lower limbs

51

Cauda equina

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

52

Meninges in vertebrae

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

53

Gray matter in vertebrae

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

54

Dorsel/ posterior horn (Gray matter)

Receives sesnory nerve fibres

55

Ventral/anterior horn (Gray matter)

Contains soma
Give rise to efferent nerve fibres

56

Lateral gray horn

Contians somas of sympathetic neurons

57

White matter

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

58

Tracts definition

Bundle of axins in CNS