Development of nervous system Flashcards
What embryonic event takes place during the third week of embryogenesis.
Gastrulation- bilaminar becomes trilaminar
Cells of the epiblast that remain in place form the _________-
ectoderm
Some of the cells of the epiblast invaginate and form the ____________.
primitive streak
some of the cells of the epiblast detach from the epiblast and form the ________
mesoderm.
SOme of the cells detach from the epiblast and move deeper and begin replacing hypoblast cells forming _________.
endoderm
3 structures involved in development of nervous system
Notochord first
Neural tube
Neural crest
The central nervous system develops from the primitive __________.
ectoderm
The first step of the neural system development is the formation of the ___________.
neural PLATE
Neural plate becomes ____________.
Neural groove
Around week 3 the neural groove begins to close to form the neural tube.
Neural tube
The ________________ segments of the spinal cord and their corresponding dorsal and ventral roots are formed by secondary neurulation.
sacral and coccygeal
The caudal eminence joins the ___________, and its cavity becomes continuous with the neural canal.
neural tube
The peripheral nervous system develops from cells of the_________.
neural crest
During 4th week the central canal rostrally gives rise to the 3 primary brain vesicles, which are what?
prosencephalon (forebrain)
Mesencephalon (midbrain)
Rhombencephalon (hindbrain)
During 5th week the 3 primary brain vesicles divide into _____ secondary brain vesicles.
five
The optic cup and nerves bulge from the _________ to form the eye
diencephalon
Anterior horn motor neurons innervate skeletal muscle and are classified as __________.
Somatic efferent (SE)
The lateral horn motor neurons project to autonomic ganglia and are classified as ______________.
Visceral efferent (VE)
________ are paired blocks of paraxial mesoderm
Somites
Somites separate and form three main tomes? what are they and what do they develop into.
Dermatome= skin
Scleratome =vertebrae
Myotome= muscles
Within brainstem, where do sensory and motor fibers go?
sensory stay dorsolaterally
motor stay ventrallaterally
The cerebellum arises from the rostral part of the ___________.
Rhombic lip
True/False: the cerebral cortex is formed in a sequence called the “inside-out pattern of development.”
True
How do neurons find their targets?
They secrete attractant molecules, called trophic factors or signpost molecules.
