Introduction

Question 1

Functions of the NS?

Answer 1

Sensation
Intergration
Initation of motor acitivty

Question 2

What is the origin of the PNS

Answer 2

Neural crest cells from neural tube

Question 3

How many cranial nerves are there?

Answer 3

12

Question 4

How many pairs of spinal nerves are there and where are they?

Answer 4

31 pairs:
CERVICAL 8
THORACIC 12
LUMBAR 5
SACRAL 5
COCCYGEAL 1

Question 5

3 partitions of the ectoderm

3 germ layers through gastrulation

Answer 5

Outer ectoderm(epidermis skin)
Neural crest
Neural tube

Question 6

Neuralation steps:

3 steps

Answer 6

1. Contact between notochord & future floor plate
2. Folding, delamination of neural crest
3. Closure, crest migration, roof plate formed, notochord separates

Question 7

What cell type makes up the neural tube

Answer 7

PSEUDOSTRATIFIED NEUROEPITHELIUM- cells are called neural progenitors

Question 8

What is interkinetic nuclear migration

Answer 8

Movement of cell nuclei within dividing epithelial cells, specifically between the apical and basal surfaces of the tissue, in coordination with the cell cycle. This movement is a common feature of developing tissues, particularly the neuroepithelium

Question 9

Describe laminar organisation of grey matter of spinal cord?

Answer 9

9 layers

Question 10

Define Determination

Answer 10

the process whereby a cell commits to
become a particular tissue autonomously, and the
commitment is irreversible.

Question 11

Define Specification:

Answer 11

the process whereby a cell commits to
become a particular tissue autonomously, but the
commitment can be reversible.

Question 12

Define Competence:

Answer 12

the ability of a cell or tissue to respond to an
inducing signal - embryonic tissues only remain competent for a limited period of time

Question 13

Define Induction:

Answer 13

the process whereby a cell or tissue signals to
another cell or tissue in the embryo, thereby affecting the development of the responding cell or tissue

Question 14

Define Morphogen:

morphogenesis

Answer 14

protein that gives positional information to
cells via a concentration gradient and alters cell fates

Question 15

Define positional infomation

Answer 15

The transplanted cells retain their identities
(knowledge of which flag they belong to) but also respect the positional effects of the
host (ie their position within the other flag) The transplanted cells have lost competence to
respond to the signal from the host

Question 16

Where is Sonic hedgehog produced

Answer 16

In notochord and floor plate

Question 17

Four stages that pluripotent ectodermal cells have to pass to become Neural precursor cells or progenitor cells and then Neurons

Answer 17

1. Have Competence: becoming progenitors in different regions
2. Specification: stay or leave from progenitor characteristics (intermediate; reversible)
3. Determination (commitment): entering neural differentiation pathway (neuronal subtype has been
   selected)
4. Differentiation: exit cell cycle and express neuron-specific genes

Question 18

Which germ layer does neural creat come from?

Answer 18

ectoderm

Question 19

What stage are cells in basal side

Answer 19

Neuron and specifying

Question 20

What stage are cells on apical side

Answer 20

progenitors- not get differenitate into neruons.

Once they go through mitosis they move up to basal and become neurons

Question 21

Once cell is determained

Answer 21

Cannot be respecified

Question 22

Specified can be

Answer 22

re specified by the enviroment

Question 23

Example of ventral induction

Answer 23

SHH

Question 24

What specifies the ventral floor plate

Answer 24

Notochord

Question 25

Describe ventral neural patterning

Answer 25

Graded SHH activity

Question 26

origin of notochord and role

Answer 26

mesoderm To specify/pattern the neural tube progenitors

Question 27

What do the dorsal progenitors of nerual tube differentiate into?

Answer 27

Neurons and glia at the top | neural creat cells dissociate from roof plate

Question 28

Describe 3 regions of nerual plate differentiation

Answer 28

1. neurons and glia at the top 2. Interneruons in the middle 3. Motor neurons in the ventral bottom

Question 29

# Key stages in neuron generation Four stages that pluripotent ectodermal cells have to pass to become Neural precursor cells or progenitor cells and then Neurons

Answer 29

1. Have Competence: becoming progenitors in different regions 2. Specification: stay or leave from progenitor characteristics (intermediate; reversible) 3. Determination (commitment): entering neural differentiation pathway (neuronal subtype has been selected) 4. Differentiation: exit cell cycle and express neuron-specific genes

Question 30

Core concept and translatable idea

Answer 30

Epistasis- translates to mutants in signalling pathway

Question 31

mechanoreceptors fibres & Laminae | Post natal fine touch laminae

Answer 31

afferant A fibres Laminae 3-5

Question 32

Noiceptors fibres & laminae | Post natal fine touch laminae

Answer 32

afferent C fibres Laminae 1-2

Question 33

Define neuralation

Answer 33

process of how the ectoderm gives rise to the Nervous System

Question 34

Ear to hair cells

Answer 34

otic placode ectoderm Induction Specification Neurogensis Hair cells

Question 35

Technique to visulise SHH

Answer 35

mRNA in situ hybridisation

Question 36

What is organisation of touch receptors in embryonic vs post-natal pahse

Answer 36

Crude touch in embryo- Both A&C fibres synapse onto same laminae Fine touch Post-natal, Not they are specified in specific spinal laminae. - become more organised

Question 37

Where do different sources of neural stem cells come from?

Answer 37

Embryo- ectoderm nerual crest cells Adult- in SVZ & SGZ | Adult- hippocampus and olfactory