BMS11004 - WEEK 5 TUESDAY

Question 1

what is neural place

Answer 1

small patch of ectodermal tissue on dorsal surface of developing embryo, known as “embryonic stem cells”

Question 2

what 3 layers does gastrulation form?

Answer 2

endoderm (“gastrula, lining of viscera)
mesoderm (bones, muscles, connective tissue)
ectoderm (skin and nervous stem, form neural plate)

Question 3

how many days at which are neural plate formed

Answer 3

17 days

Question 4

at how many days is neurulation occur

Answer 4

22days

Question 5

briefly explain neurulation

Answer 5

1. neuroectoderm forms (ectoderm anterior to primitive streak thicken)
2. becomes neural plate
3. neural groove and folds due to uneven cell divisions
4. form neural tube (CNS) and neural crest (PNS)
5. neural tube later become ventricular system

Question 6

what is a somite

Answer 6

part of mesoderm that becomes vertebrae and associated muscles (innervated by somatic motor nerves)

Question 7

what neuron could potentially form neural crest

Answer 7

sensory, dorsal root ganglia neurons
neurons of PNS

Question 8

why are women advised to take folic acid during conception and pregnancy

Answer 8

failure to close neural tubes causes anencephaly (unclosed at top, undeveloped forebrain), spina bifida (bottom not fully closed)
reduce risk of neural tube defects by 90% via influencing DNA synthesis

Question 9

what is differentiation

Answer 9

neural tube cells start proliferating, moving and differentiating
rostral cells undergo more differentiation to become forebrain

Question 10

outline process of differentiation from neural tube, to brain structure

Answer 10

1. neural tube form 3 brain vesicles (prosencephalon “forebrain”, mesencephalon “midbrain”, rhombencephalon “hindbrain”)
2. forebrain secondary differentiation into telencephalic vesicles (become telencephalon), diencephalon, optic vesicles (becomes optic stalk/nerve)

Question 11

does the prosencephalon become forebrain, midbrain or hindbrain

Answer 11

forebrain

Question 12

does the mesencephalon become forebrain, midbrain or hindbrain

Answer 12

midbrain

Question 13

does the rhombencephalon become forebrain, midbrain or hindbrain

Answer 13

hindbrain

Question 14

what does telencephalon differentiate into

Answer 14

cerebral cortex (thin layer with many neuron, connected via corpus callosum) and basal telencephalon (eg: amygdala, basal ganglia)

Question 15

whats structure for cerebral cortex

Answer 15

grey matter, convoluted, large furrows (fissures), small fissure (sulci), gyri (ridge inbetween)

Question 16

what 2 main structures does diencephalon differentiate into (and 1 other, less important structure)

Answer 16

thalamus and hypothalamus

SCN (suprachiasmatic nucleus)- circadian 24hr rhythms

Question 17

what does thalamus do (a part of diencephalon)

Answer 17

inner chamber, divide into different nuclei
eg: sensory relay, transmits info from receptor to cortex

Question 18

what does hypothalamus do (part of diencephalon)

Answer 18

autonomic and glandular 4F

Question 19

what is cortical white matter?

Answer 19

white matter thats coming to/from cortex

Question 20

what is corpus callosum?

Answer 20

huge white matter tract connecting both hemispheres

Question 21

what does midbrain differentiate into

Answer 21

tectum (dorsal midbrain), tegmentum (ventral midbrain)

Question 22

what does tectum include

Answer 22

inferior auditory colliculi, superior visual colliculi (REM saccade)

Question 23

what does tegmentum divide up into

Answer 23

periaqueductal grey, RN, substantia nigra

Question 24

what does periaqueductal grey do (tegmentum midbrain)

Answer 24

species specific behaiviour and lordosis, control pain

Question 25

what does red nucleus do (tegmentum midbrain)

Answer 25

motor system, bilateral coordination

Question 26

what does substantia nigra do (tegmentum midbrain)

Answer 26

motor system, damage lead to Parkinsons disease

Question 27

what does hindbrain split into

Answer 27

myelencephalon, metencephalon

Question 28

what does the myelencephalon do

Answer 28

medulla oblongata= respiratory rhythm, arousal, RAS, BPw

Question 29

what do metencephalon do

Answer 29

pons (nuclei for sleep and arousal)
cerebellum (integrates sensory info to modify motor output, coordinate and smooth movements, damage = Parkinson)

Question 30

is medulla oblongatas formed at rostral or caudal part of metencephalon

Answer 30

caudal

Question 31

what are rhombic lips, in relation to metencephalon

Answer 31

rhomic lips form at dorsal aspect to create cerebellum

Question 32

what is structure of cerebellum

Answer 32

many neurons, large SA via folia (folds)
2 hemispheres joined by vernis
deep cerebellar (output neuron) and pontine nuclei (pons)
10% CNS vol, 50% CNS neurons

Question 33

what is function of cerebellum

Answer 33

coordinate movements, balance, posture

Question 34

what does the cerebellum receive inputs from

Answer 34

cerebral cortex (planning and initiate movement)
vestibular system (balance)
occulars

Question 35

whats function of vestibulocerebellum

Answer 35

balance

Question 36

whats function of spinocerebellum

Answer 36

muscle stretch receptors

Question 37

whats function of cerebrocerebellum

Answer 37

projection from sensorimotor cortex, for motor coordination