Neural Tissues

Question 1

What is the difference between the central nervous system and the peripheral nervous system?

Answer 1

• CNS - brain and spinal cord - information processing including reflexes and behaviour
• PNS - cranial nerves and spinal nerves - Sensory detection and motor activation

Question 2

• CNS - … and … cord - information processing including … and …
• PNS - … nerves and … nerves - Sensory detection and … activation

Answer 2

• CNS - brain and spinal cord - information processing including reflexes and behaviour
• PNS - cranial nerves and spinal nerves - Sensory detection and motor activation

Question 3

Which embryonic layer/tissue is the nervous system derived from?

Answer 3

Ectoderm

Question 4

What are the main functions of neuroglia?

Answer 4

• Glia differ from neurons
• Glia: have no action potentials, do not form synapses, are able to divide (most common source of tumours of NS) and form myelin sheaths

Question 5

What is a Node of Ranvier?

Question 6

• … neuron: transmit sensory information to brain/spinal cord
• … neuron: motor neuron transmitting information from brain to effector organ i.e. muscle

Answer 6

• Afferent neuron: transmit sensory information to brain/spinal cord
• Efferent neuron: motor neuron transmitting information from brain to effector organ i.e. muscle

Question 7

A ganglion is a group of neuron cell bodies in the … nervous system (outside …)

Answer 7

A ganglion is a group of neuron cell bodies in the peripheral nervous system (outside CNS)

Question 8

• … ganglia are associated with neurons of the autonomic nervous system e.g. parasympathetic ganglion
• They have … neurons and … nuclei

Answer 8

• Motor ganglia are associated with neurons of the autonomic nervous system e.g. parasympathetic ganglion
• They have smaller neurons and eccentric nuclei

Question 9

… ganglion have big neurons, central nuclei - example is a … root ganglion

Answer 9

Sensory ganglion have big neurons, central nuclei - example is a dorsal root ganglion

Question 10

In CNS groups of neurons are called…

Answer 10

nucleus

Question 11

What is myelin?

Answer 11

Myelin is an insulating layer, or sheath that forms around nerves, including those in the brain and spinal cord

Question 12

What is a Brodmann area?

Answer 12

• Names regions
• 2 maps - just for our benefit - do not have to learn these regions
• Should be able to understand how to navigate it when given to you

Question 13

Directions in human prefrontal cortex

Answer 13

Question 14

Neurons

Answer 14

Question 15

What is the purpose of myelin?

Answer 15

• Myelin is an insulating layer, or sheath that forms around nerves, including those in the brain and spinal cord
• Purpose - increase conduction velocity (so does increased diameter)

Question 16

Neuron classification:

• Neurons: multipolar, bipolar and unipolar
• All neurons have just 1 …
• Majority of neurons several … = multipolar

Answer 16

• Neurons: multipolar, bipolar and unipolar
• All neurons have just 1 axon
• Majority of neurons several dendrites = multipolar

Question 17

Important neurons

• … cells - neocortex
• … cell - cerebellum
• … root ganglion - sensory neuron

Answer 17

• Pyramidal cells - neocortex
• Purkinje cell - cerebellum
• Dorsal root ganglion - sensory neuron

Question 18

Neuron classification:

• … - one dendrite and one axon - least numerous - sensory neurons e.g retina
• …-… one axon and one dendrite e.g. dorsal root ganglion

Answer 18

• Bipolar - one dendrite and one axon - least numerous - sensory neurons e.g retina
• Pseudo-unipolar - one axon and one dendrite e.g. dorsal root ganglion

Question 19

Synaptic transmission - chemical

• Chemical Synapse:
  
  • physical … (30nm)
  • Neurotransmitter released from presynaptic neuron through to the postsynaptic cell receptor - triggers … signal in this cell
  • Signalling is not in … direction - moving backward

Answer 19

• Chemical Synapse:
  
  • physical gap (30nm)
  • Neurotransmitter released from presynaptic neuron through to the postsynaptic cell receptor - triggers electric signal in this cell
  • Signalling is not in Retrograde direction - moving backward

Question 20

Post-synaptic cell examples

Answer 20

neuron, myocyte or gland

Question 21

• … - single neuron sends its output signal to many neurons
• … - multiple inputs influence a single neuron

Answer 21

• Divergent - single neuron sends its output signal to many neurons
• Convergent - multiple inputs influence a single neuron

Question 22

… occur only in CNS - neither motor nor sensory - process signals

Answer 22

Interneurons occur only in CNS - neither motor nor sensory - process signals

Question 23

Interneurons (also known as association neurons) are neurons that are found exclusively in the … nervous system.

Answer 23

Interneurons = Interneurons (also known as association neurons) are neurons that are foundexclusively in the central nervous system. That means that they are found in the brain and spinal cord and not in the peripheral segments of the nervous system

Question 24

Brodmann area

Answer 24

1,2,3

Question 25

* Glia differ from neurons * Glia: have no ... ..., do not form ..., are able to ... (most common source of tumours of NS) and form myelin ...

Answer 25

* **Glia differ from neurons** * **Glia: have no action potentials, do not form synapses, are able to divide (most common source of tumours of NS) and form myelin sheaths**

Question 26

Directions in human prefrontal cortex

Answer 26

Question 27

What glial cell type is this?

Answer 27

Oligodendrocytes (CNS)

Question 28

_Many more glial cells than neurons_ * Neurons - basic nerve cells, ... conducting * Glial cells - s.. and p..

Answer 28

* **Neurons - basic nerve cells, impulse conducting** * **Glial cells - supportive and protective**

Question 29

_Glial cell types - overview_ * ... cells - set of epithelial cells lining ventricles - determine fluid make up inside of this system - cilia and large SA to determine what fluid goes in and salt * Astrocyte - star shape - support and controls blood vessels * ... ... - covers overall brain (innermost) * Oligodendrocyte - CNS - making or forming myelin sheath * ... cells - almost like immune cells - external / unwanted pathogens - keep it clean

Answer 29

* **Ependymal** cells - set of epithelial cells lining ventricles - determine fluid make up inside of this system - cilia and large SA to determine what fluid goes in and salt * Astrocyte - star shape - support and controls blood vessels * **Pia** **mater** - covers overall brain (innermost) * Oligodendrocyte - CNS - making or forming myelin sheath * **Microglial** cells - almost like immune cells - external / unwanted pathogens - keep it clean

Question 30

_Oligodendrocytes_ * In ... only - Not ... * Production/maintenance of myelin ... * ... oligodendrocyte myelinates ... axons (from different neurons)

Answer 30

* **In CNS only - Not PNS** * **Production/maintenace of myelin sheath in CNS** * **One oligodendrocyte myelinates multiple axons (from different neurons)**

Question 31

Approximately how many neurons are in the brain?

Answer 31

100 billion

Question 32

Name a place where you would find afferent neurons.

Answer 32

near brain and spinal cord

Question 33

Name a place where you would find efferent neurons

Answer 33

The cell bodies of efferent neurons are located within the central nervous system.

Question 34

_Astrocytes (CNS)_ * Supports neurons: * Assists neuronal ... * Protects neurons from ... substances * Little feet - affect endothelium and influence blood flow and blood ... ... * ...-shaped

Answer 34

* Supports neurons: * Assists neuronal **development/growth (Neurotrophic - neuron growth)** * Protects neurons from **harmful** substances * Little feet - affect endothelium and influence blood flow and **blood brain barrier** * **Star**-shaped

Question 35

What glial cell type is this?

Answer 35

astrocyte

Question 36

_Microglia (CNS)_ * Immune cells - protect neurons from disease, migrate to ... sites, engulf microbes /debris * MOST ... but these have ... origin like other immune cells * Also develop from ...

Answer 36

* Immune cells - protect neurons from disease, migrate to **injury** sites, engulf microbes /debris * MOST **ECTODERM** but these have **mesodermal** origin like other immune cells * Also develop from **monocytes**

Question 37

What glial cell type is this?

Answer 37

Microglia - CNS - protect neurons from disease - mesodermal origin like other immune cells

Question 38

_Ependymal cells (CNS)_ * Line brain ... and central canal of spinal cord - Responsible for forming and maintaining ... in ventricles * The cilia and microvilli on ... membrane allows for increase SA on apical membrane (extend into ventricle) to allow for interaction with ... and ...

Answer 38

* Line brain ventricles and central canal of spinal cord - Responsible for forming and maintaining **CSF** in ventricles * The cilia and microvilli on **apical** membrane allows for increase SA on apical membrane (extend into ventricle) to allow for interaction with **fluid** and **salts**

Question 39

Ependymal cells (CNS) have what which increase SA?

Answer 39

Cilia and microvilli on apical membrane - Allows for increase SA on apical membrane (extend into ventricle) to allow for interaction with fluid and salts

Question 40

_Schwann cells (PNS)_ * Production/maintenance of ... ..., PNS regeneration * ... axon wrapped per Schwann cell - compare to oligodendrocytes in CNS

Answer 40

* Production/maintenance of **myelin sheath,** PNS regeneration * **1** axon wrapped per Schwann cell - compare to oligodendrocytes in CNS

Question 41

Where are Schwann cells found?

Answer 41

PNS

Question 42

_Satellite cells (PNS)_ * ... neurons, regulate ... of materials between neurons and interstitial flui. * Perform analogous role in PNS to what ... do in CNS

Answer 42

* **Support** neurons, regulate **exchange** of materials between neurons and interstitial fluid * Perform analogous role in PNS to what **astrocytes** do in CNS

Question 43

_Glial Classifications_ * CNS: ... (4) * PNS: ... (2)

Answer 43

Question 44

_Meninges_

Answer 44

Question 45

_Glial pathology: glioma_ * Largest group of primary tumours derived from glial cells * Usually highly ... * Grow ... * Difficult to remove completely with surgery * Usually inside ...

Answer 45

* largest group of primary tumours derived from glial cells * Usually highly **malignant** * Grow **rapidly** * Difficult to remove completely with surgery * Usually inside **cranium**

Question 46

_Glial pathology: glioma_ * ... group of primary tumours derived from glial cells * Usually highly malignant * Grow rapidly * Difficult to remove completely with ... * Usually inside cranium

Answer 46

* **largest** group of primary tumours derived from glial cells * Usually highly malignant * Grow rapidly * Difficult to remove completely with **surgery** * Usually inside cranium

Question 47

_Neuroblastoma_ * Tumour (cancer) * Most common in ... and ... * Outside ... * Derived from neural crest cells from ... NS * Increased catecholamine levels (often) * Survival rates vary: depends on type * Initial prognosis is typically ... * Survivors often develop neurological problems approx ... years later * Treatment depends on type

Answer 47

* Tumour (cancer) * Most common in **children and infants** * Outside **cranium** * Derived from neural crest cells from sympathetic NS * Increased catecholamine levels (often) * Survival rates vary: depends on type * Initial prognosis is typically **good** * Survivors often develop neurological problems approx **30** years later * Treatment depends on type

Question 48

_Neuroblastoma_ * ... (cancer) * Most common in children and infants * Outside cranium * Derived from ... ... cells from sympathetic NS * Increased ... levels (often) * Survival rates vary: depends on type * Initial prognosis is typically good * Survivors often develop ... problems approx 30 years later * ... depends on type

Answer 48

* **Tumour** (cancer) * Most common in children and infants * Outside cranium * Derived from **neural crest** cells from sympathetic NS * Increased **catecholamine** levels (often) * Survival rates vary: depends on type * Initial prognosis is typically good * Survivors often develop **neurological** problems approx 30 years later * **Treatment** depends on type

Question 49

What is a Node of Ranvier?

Answer 49

Nodes of Ranvier are microscopic gaps found within myelinated axons.

Question 50

Name a cell type or place where you would find a multipolar neuron.

Answer 50

They are located in the central nervous system (brain and spinal cord) and in autonomic ganglia.

Question 51

Name a cell type or place where you would find a bipolar neuron.

Answer 51

. They are sensory neurons found in olfactory epithelium, the retina of the eye, and ganglia of the vestibulocochlear nerve.

Question 52

Name a cell type or place where you would find a pseudounipolar neuron.

Answer 52

Pseudounipolar neurons are found in the sensory ganglia of most cranial nerves, dorsal root ganglion

Question 53

Name 4 ways in which glia (in general) differ from neurons (in general).

Answer 53

Glia have no action potentials, do not form synapses, are able to divide (most common source of tumours of NS) and form myelin sheaths

Question 54

Name 4 differences between a glioma and a neuroblastoma.

Answer 54

* Glioma usually inside cranium, whereas neuroblastoma outside cranium * Glioma derived from glial cells wherfeas neuroblastoma from neural crest cells from sympathetic NS * Neuroblastoma associated with increased catceholamine levels (often), glioma not * Neuroblastoma most common in children and infants , glioma in adults

Question 55

Name two locations where you would expect to find ganglia in the peripheral nervous system.

Answer 55

parasympathetic galgnion dorsal root ganglion

Question 56

Name two differences between an oligodendrocyte and a Schwann cell.

Answer 56

oligodendrocyte - CNS - one oligodendrocyte myelinates multiple axons Schwann cell - PNS - 1 axon per schwann cell

Question 57

What is the function of a Schwann cell?

Answer 57

produce/maintain myelin sheath, PNS regeneration

Question 58

What is the function of an oligodendrocyte?

Answer 58

production/maintenance of myelin sheath in CNS

Question 59

What is the function of an ependymal cell?

Answer 59

Forming and maintaining CSF in ventricles

Question 60

What is the function of a satellite cell in the peripheral nervous system?

Answer 60

support neurons, regulate exchange of materials between neurons and interstitial fluid

Question 61

What is the function of a microglial cell?

Answer 61

immune cell - protect from disease

Question 62

What kind of axon fibres have the fastest conduction velocity?

Answer 62

myelinated

Question 63

What kind of neurons (histologically) would you expect to find in the dorsal root ganglia?

Answer 63

pseudo-unipolar

Question 64

Which part of the prefrontal cortex is nearest to the primary auditory cortex (on the outer shell of the temporal lobe): ventrolateral, ventromedial, dorsolateral, dorsomedial?

Answer 64

ventrolateral?

Question 65

Which part of the prefrontal cortex is nearest to the primary auditory cortex (on the outer shell of the temporal lobe): ventrolateral, ventromedial, dorsolateral, dorsomedial?

Answer 65

ventrolateral?