Structure And Organisation Of The Nervous System

Front 1

What are the functions of the nervous system?

Back 1

1. Co-ordination of different physiological systems / functions

2. Acts in parallel with the endocrine system

3. Enables us to respond rapidly to our environment: External stimuli and internal stimuli

4. Responses can be simple (e.g reflexes) or complex (learning and memory)

Front 2

What are the two major subdivisions of the nervous system?

Back 2

1. Central Nervous System

2. Peripheral Nervous System

Front 3

What are the different types of Adult CNS cell?

Back 3

1. Endothelial cells

2. Pericytes

3. Ependymal cells

4. Astrocyte

5. Oligodendrocyte

6. Myelinated and unmyelinated neurons

Front 4

What are the different functional classes of neurons?

Where do they transmit their signals from and to?

Back 4

1. Afferent / Sensory Neurons (Sensory Receptor -> CNS)

2. Efferent / Motor Neurons (CNS -> Effector)

3. Interneurons (Neuron -> Neuron)

Front 5

What is the most abundant variety of neuron?

Back 5

Interneurons - 99% of all neurons

Front 6

Where are interneurons found?

Back 6

Exclusively in the central nervous system

Front 7

What is grey matter made up of?

Back 7

Interneurons, cell bodies & dendrites of efferent neurons, synapses and glia.

Front 8

What is white matter made up of?

Back 8

Made up of bundles of myelinated axon bundles.

Front 9

What distinguishes grey matter from white matter?

Back 9

Grey matter is distinguished from white matter, in that it contains numerous cell bodies and relatively few myelinated axons, while white matter contains relatively very few cell bodies and is composed chiefly of long-range myelinated axon tracts.

Front 10

What are the different types of neuralglial cells?

Back 10

1. Macroglia

2. Microglia

Front 11

What are the functions of glial cells?

Back 11

1. Metabolic buffering / support - buffers extracellular Na+ and K+ ions

2. Neurotransmitter removal from extracellular space

3. Scavenger function

4. Control the blood - brain barrier

5. Guide growth of developing neurons

6. Some glial cells may act as neural stem cells.

Front 12

What is the blood brain barrier?

Back 12

The blood brain barrier is a barrier which facilitates selective transport of molecules into the nervous system.

Front 13

What is 'negotiation' in respect to the blood brain barrier?

Back 13

Microglia and some immune cells can negotiate their way past the blood brain barrier in certain disease conditions (e.g HIV)

Front 14

What are the fluid filled cavities which surround the CNS brain called?

What are they filled with?

Back 14

1. Ventricles

2. Fluid in the ventricles is called the cerebrospinal fluid

Front 15

What is the function of the cerebrospinal fluid?

How much fluid is regenerated a day?

Back 15

1. Provides physical support and nourishment

2. 500ml per day

Front 16

Label the ventricles

Back 16

1: Lateral Ventricles

2: Interventricular foramen

3: Third Ventricle

4: Cerebral Aqueduct

5: Fourth Ventricle

6: Cerebral canal

Front 17

What component of the brain produces cerebrospinal fluid?

Back 17

CSF is produced by the choroid plexus system.

Front 18

What is the choroid plexus?

Back 18

A special population of ependymal cells found in the third and fourth ventricles.

Front 19

What can be gleaned from the contents of the cerebro spinal fluid?

Back 19

The health status of the nervous system:

Lymphocytes / bacteria = bacterial infection or an autoimmune disease

Increased levels of the protein Transferrin is indicative of a leaky choroid plexus.

Front 20

What is the overall organisation of the nervous system:

Back 20

Front 21

1. How many pairs of nerves are found in the peripheral nervous system (PNS).

2. What are the two types of nerve?

3. How many of each are there?

Back 21

43 total pairs of nerves:

12 pairs of cranial nerves

31 pairs of spinal nerves

Front 22

What does the 'enteric' nervous system refer to?

Back 22

A meshwork of neurons innervating gut muscles as well as mucosal cells.

Front 23

What is the main role of the enteric nervous system?

Back 23

Peristalsis

Front 24

What are the secondary roles of the enteric nervous system?

Back 24

1. Gut bacteria interaction

2. Infection and hyperactvity of autonomic nervous system - irritable bowel syndrome

Front 25

List the exclusively afferent cranial nerves and their roles.

Back 25

1. Olfactory - smell input

2. Optic - eye input

3. Vestibulocochlear - Information from inner ear

Front 26

List the exclusively efferent cranial nerves and their roles.

Back 26

1. Accessory - Innervates neck muscles

2. Hypoglossal - Innervates tongue muscles

Front 27

List the cranial nerves which are a mixture of afferent and efferent nerves and their roles.

Back 27

1. Oculomotor - Transmits info from & innervates skeletal eye muscles

2. Trochlear - Transmits info from & innervates down and lateral skeletal eye muscles

3. Trigeminal - Transmits info from facial sensors in teeth, mouth and face. Innervates chewing muscles.

4. Abduceus - Transmits info from & innervates lateral eye muscles.

5. Facial - Transmits info from tastebuds & innervates facial muscles for expression, swallowing and salivary glands.

6. Glossopharyngeal - Transmits info from tastebuds at back of tongue and in auditory tube skin. Innervates skeletal muscles for swallowing and parotoid salivary gland.

7. Vagus - Transmits info from receptors in thorax and abdomen. Innervates skeltal muscles of pharynx, larynx as well as smooth muscles and glands in the thorax and abdomen

Front 28

1. What are the different types of spinal nerve?

2. How many of each nerve are there?

Back 28

There are:

8 pairs of cervical

12 pairs of thoracic

5 pairs of lumbar

5 pairs of sacral

1 pair of coccygeal

Front 29

What are the differences between the nerves of the somatic and autonomic nervous system? (in general terms)

Back 29

Autonomic has the presence of ganglions, including pre and post ganglionic fibres.

Front 30

What does the autonomic nervous system control?

Back 30

Things we don't need to think about:

Motor control of heart, smooth muscle and glands.

Front 31

What does the sympathetic nervous system allow response to?

Back 31

Sympathetic nervous system allows response to stress.

Front 32

What does the parasympathetic nervous system promote?

Back 32

Promotes routine activities, conserving the body's resources and restoring homeostasis.

Front 33

What effects do the parasympathetic and sympathetic nervous system have on the liver?

Back 33

Parasympathetic has no effect however the sympathetic promotes glycogenolysis and gluconeogenesis: an act to increase the blood glucose levels.

Front 34

What is different about the locations of the ganglia in the sympathetic and parasympathetic nervous system?

Back 34

Sympathetic ganglia are found closer to the spinal cords in structures called sympathetic trunks.

Parasympathetic ganglia are found close to the organs they are innervating.

Front 35

Where do the pre-ganglionic neurons of the sympathetic nervous system leave from?

Back 35

Leave from the thoracic and lumbar regions of the spinal cord.

Front 36

What is the neurotransmitter of the pre ganglionic neurons in the sympathetic nervous system?

Back 36

Cholinergic - therefore use acetylcholine as a neurotransmitter.

Front 37

What is the neurotransmitter of the post ganglionic neurons in the sympathetic nervous system?

Back 37

Noradrenergic - the neurotransmitter is noradrenaline.

Front 38

What is the neurotransmitter across all parasympathetic nervous system neurons?

Back 38

Acetylcholine

Front 39

Where do parasympathetic nervous system nerves leave the CNS from?

Back 39

The brain stem and sacral regions of the spinal cord (from the craniosacral system)