Which of the three germ layers does the nervous system arise from?
Which structure that arises in the ectoderm forms the basis of the nervous system?
What happens to the neural plate once it starts to develop?
Starts to invaginate/fold > forms tube beneath ectoderm
What is the tube that forms beneath the ectoderm when the neural plate invaginates known as?
Where does the neural groove lie in relation to the notochord?
Neural groove is above notochord
What happens to the neural groove after it begins to form?
Deepens > edges come together and join in midline > creates a tubular structure that can break free from overlying ectoderm
What is the tubular structure formed from the folding of the neural groove called?
How is the neural tube formed?
Neural groove deepens > edges come together and join in midline > creates a tubular structure that can break free from overlying ectoderm
What is the first physical structure of the nervous system to form?
Describe the neural tube?
Simple tube Single cell thick
What does the neural tube go on to form?
Brain and spinal cord
What does the hole in the neural tube go on to form?
What does the ventricular system arise from?
Hole in the neural tube
Describe the gradient that exists in the neural tube?
Rostral to caudal gradient
What is the consequence of the rostral to caudal gradient in the neural tube?
Development occurs faster at the head end and slower at the tail end Rostral end is older
Describe the order of neural tube closure?
Closure tends to start towards middle, and leave ends of neural tube open
Zippers shut up and down from that midpoint
Gove examples of birth defects that arise as a result of failure of closure of the neural tube?
Are the five 'zipping' processes in the closure of the neural tube dependent on each other?
No, largely indepedent
Briefly describe the segmentation process of the neural tube?
Rostral end of tube starts to well
3 distinct vesicles form
Further segmentation of these vesicles occurs
Name the three vesicles initially formed by the segmetation of the neural tube? Which brain structure does each vesicle correspond to?
What does the prosencephalon further divide into?
Telencephalon and diencephalon
What does the rombencephalon further didvide into?
Seven segments (r1-r7)
Whathappens to the part of the neural tube that does not become segmented?
Intact neural tube goes on to form spinal cord
What do the pons and cerebellum arise from?
Metencephalon division of rhombencephalon
What does the medulla arise from?
Myelencephalon division of rhombencephalon
What are the major derivatives of the telencephalon?
Cortex, basal ganglia, hippocampus
What are the major derivatives of the diencephalon?
Thalamus and hypothalamus
What does the caudal part of the neural tube go on to form?
Describe the structure of the developing brain after neural tube segmentation has occured?
series of thin-walled bubbles
What is the neural crest?
cells tha lie between the neural groove and neural tube after the neural tube forms