Neural tissues

Question 1

CENTRAL VS PERIPHERAL NERVOUS SYSTEM

i) which division of the NS is involved in information processing inc reflexes and behaviour?
ii) which two sets of nerves is the peripheral nervous system comprised of?
iii) which germ layer is the nervous system derived from?
iv) what is a group of cell bodies outside the CNS called?

Answer 1

i) central
ii) spinal nerves and cranial nerves
iii) ectoderm
iv) a ganglion

Question 2

GANGLIA

i) which type of ganglion has small neurons and eccentic nuclei?
ii) which type of ganglion has big neurons and a central nuclei? give an example
iii) label the types of ganglion seen in A and B

Answer 2

i) parasympathetic ganglion
ii) sensory ganglion eg DRG
iii) A = psym (eccentric nuc), B = sensory (central nuc)

Question 3

AREAS OF THE HUMAN PREFRONTAL CORTEX

i) label A-F
ii) which brodmann area is the primary motor cortex?
iii) which brodmann area is the primary visual cortex?

Answer 3

i) A = dorsal, B1 = rostral, B2 = caudal, C = dorsolateral, D = ventrolateral, E = dorsomedial, F = ventromedial
ii) primary motor is brodmann area 4
iii) primary visual is brodmann area 17

Question 4

NEURONS

i) which type of neuron has a cell body and extends one or more processes?
ii) label A-C
iii) what is the main role of myelin? (2) what is it made of?
iv) what number of axons does every neuron have?
v) where are pyramidal cells found? where are purkinje cells found?

Answer 4

i) CNS neuron
ii) A = dendrites, B = axon hillock, C = axon collaterals

iii) myelin increases conduction velocity and diameter of axon
- made of layers of cell membrane

iv) one
v) pyramidal cell in the neocortex, purkinje cells in the cerebellum

Question 5

NEURON CLASSIFICATIONS

i) what type of neuron is A? give an example of where this may be found
ii) what type of neuron is B? give an example
iii) what type of neuron is C?
iv) which type of neurons only occur in the CNS? what are they responsible for?

Answer 5

i) A = bipolar (sensory neurons of retina)
ii) B = pseudounipolar eg DRG
iii) multipolar
iv) interneurons - responsible for processing

Question 6

CHEMICAL SYNAPTIC TRANSMISSION

i) what is the presynaptic cell always?
ii) name three things the post synaptic cell can be
iii) how big is the gap? which way does signalling exclusively occur?
iv) what is divergent signalling? what is convergent signalling?

Answer 6

i) a neuron
ii) neuron, gland, myocyte
iii) big gap (30nm), signalling only forward

iv) divergent = single neuron sends output signal to many
convergent = multiple inputs influence a single neuron

Question 7

GLIAL CELLS

i) do they fire action potentials?
ii) do they form synapses
iii) can they divide?
iv) what do they allow production of?
v) are there more neurons or glial cells?

Answer 7

i) no
ii) no
iii) yes - neurons cant usually divide
iv) allow formation of myelin sheaths
v) glial cells (support cells)

Question 8

TYPES OF GLIAL CELLS

i) which epithelial cells line the ventricles of the brain?
ii) which support cells are star shaped and control blood vessels
iii) which meningeal layer is made of glial cells?
iv) which glial cells are only found in the CNS and make myelin? name another role they have

Answer 8

i) ependymal cells
ii) astrocytes
iii) pia mater
iv) oligodendrocytes - also act like immune cells

Question 9

OLIGODENDROCYTES

i) what do they produce and maintain?
ii) which division of the nervous system are they found in?
iii) how many axons does one oligo myelinate?
iv) how does it make contact with the neuron

Answer 9

i) produce and maintain myelin sheath
ii) CNS
iii) one oligo myelinates many axons
iv) weaps around the specific part of the neuron that it wants to myelinate

Question 10

ASTROCYTES & MICROGLIA

i) name two roles of astrocytes? which NS division are they found in
ii) which two things do astrocytes influence?
iii) name three roles of microglia? which NS division are they found in?
iv) which germ layer do microglia originate from?

Answer 10

i) assist neuronal development and growth, protect neurons in CNS
ii) influence blood flow and the blood brain barrier
iii) immune, protect neurons from disease, migrate to injury sites and engulg microbes - in CNS
iv) mesoderm

Question 11

EPENDYMAL CELLS

i) which two cavities do they line?
ii) what is their main role?
iii) what property do they have that increases surface area?

Answer 11

i) brain ventricles and central canal of the spinal cord
ii) form CSF
iii) cillia and microvilli on apical membrane

Question 12

SCHWANN CELLS & SATELLITE CELLS

i) which division of the NS are they found in?
ii) what is schwann cell role?
iii) how many neurons does each schwann cell contact?
iv) what other cells do satellite cells perform the same role as?
v) name two roles of satellite cells

Answer 12

i) only PNS
ii) produce and maint the myelin sheath
iii) one axon wrapped per schwann cell
iv) satellite cells = astrocytes
v) support neurons, regulate exchange of nutrients bet neurons and intersitial fluid

Question 13

MENINGES

label meningeal layers A-C

Answer 13

A = dura, B = pia, C = arachnoid

Question 14

GLIAL AND NEURAL PATHOLOGY

i) which glial tumour is the largest group of tumours derived from glial cells?
ii) where are the above tumours usually found?
iii) where is neuroblastoma usually found? which cells is it derived from?
iv) what problems can neuroblastoma survivors develop 30 years later?

Answer 14

i) glioma
ii) inside the cranium

ii) extra cranial
- derived from neural crest cells from the sympathetic NS

iv) neurological problems