Ch 2 Flashcards
why learn about the development of the nervous sys
-helps us understand the adult nervous sys organization
why learn about the development of the nervous sys pt 2
-helps us understand some common congenital malformations & diversity in development
neurodevelopment
-billions of neurons are formed during neurogenesis
-they migrate to final destinations
-they begin making connections with other neurons
neural tube formation significance
-usu when mom’s don’t know that they’re pregnant; so if drugs/substances are used, it could cause great harm
-usu when miscarriage happens
atypical events during development
-genetic issues
-chromosomal issues
-infections
-exposure to meds
-chemicals or other agents
-the env
teratogens
-drugs or other agents that cause atypical development
-env, drugs, alcohol
-timing
-genetics of fetus or mother
atypical events
-nutrition
-stress
-maternal age
-paternal factors affecting sperm
craniorachischisis
-complete failure of neural tube to close (sides do not touch at all); incompatible with life
spina bifida occulta
-atypical formation of vertebral column only
-most mild type
meningocele
-herniation of the meninges only
-a little more severe
myelomeningocele
-herniation of the spinal cord & meninges
-very severe
alpha-fetoprotein
-normally produced by a fetus, and is used to screen for fetal abnormalities
holoprosencephaly
-partial or complete failure of the prosencephalon (forebrain) to separate into the diencephalon and telencephalon
-usu fatal
later fetal dev
-rapid growth is occurring and cells are moving in places that they should not be in
fetal alcohol syndrome
-most common cause of intellectual disabilities and the leading preventable cause of congenital malformations
neural plate
-flat circle
neural groove
-the line in the middle
neural fold
-left and right side of the plate
anencephaly
-failure of the head end of the tube to close resulting in absent cerebral hemispheres
At the beginning of week ________ of development the two neural folds begin to fuse together at midline to form the beginning stages of the neural tube.
-week 3
The zipping up for the neural tube starting from the center outward and completely closing by the end of week four is known as what?
-primary neurulation
Which of the following eventually become many structures that lie within peripheral nervous system?
-neural crest cells
The rhombencephalon divides into which secondary vesicles?
Metencephalon & Myelencephalon
The prosencephalon divides into which secondary vesicles?
-telencephalon
-diencephalon
The mesencephalon divides into which secondary vesicles?
-mesencephalon
prosencephalon
-forebrain
mesencephalon
-midbrain
rhombencephalon
-hindbrain
telencephalon
-cerebral hemispheres
diencephalon
-thalamus/hypothalamus
metencephalon
-pons, cerebellum
pontine flexure
-pons, medulla
myelencecephalon
-medulla
cervical flexure
-brainstem
-spinal cord
secondary vesicles
-occur in the 5th week
flexure that stays the same in adulthood
-cephalic flexure
alar plate
-sensory
-dorsal
-top part of circle
basal plate
-motor
-ventral
-bottom part of circle
ectoderm
-outside
sulcus limitans
-point part in between the alar & basal plate
endoderm
-inside
mesoderm
-middle
what happens in the fourth week?
-neural tube forms (brain, spinal cord)
-there are neural crest cells
