Nuchal
development
Neurulation
The
development of a
fully -
formed
organism from a fertilised
egg is called
embryogenesis .
All endoderm) formed
germ layers ( ectoderm ,
tissues are derived from three initial mesoderm
,
cells to
via
gastrulation during embryonic development the
embryo from blastula
single layer of
→
.
process that
changes a with a
containing multiple layers of cells .
In chordates flexible notochord will develop during formation
,
a
gastrulation and lead to the
subsequent
of a neural tube .
The formation of a neural tube in
embryonic chordates occurs via the process of neurulation .
1 Notochord forms from mesoderm cells after complete
.
soon
gastrulation is .
2.
Signals from notochord cause inward
folding of ectoderm at the neural plate .
3. Ends of neural plate fuse and disconnect to form an autonomous neural tube .
I 2 3
1
Neurulation in a Xenopus Embryo Functions
, Spina Bifida
Closure of a neutral tube does not occur
simultaneously along the entire
length of the
embryo .
↳ The area where the brain forms is well advanced over the caudal 1 tail )
region, where closure occurs more
slowly .
Spina bifida is a birth defect
resulting in the incomplete closure of the neural tube ( it is associated with the vertebrae )
It is found in the lumbar and sacral where closure is
areas →
regions slowest .
The vertebral
processes do not fuse, leaving the spinal cord nerves exposed and prone to damage .
Trust forward or
laterally
Spina bifida Occult a
.
>
splits in the vertebrae are small
,
does not able the spinal cord does not protrude .
Spina bifida
Cystic a >
meningeal cyst forms which may include the spinal elements .
↳ Extreme cases →
paralysis or bladder dysfunction .
development
Neurulation
The
development of a
fully -
formed
organism from a fertilised
egg is called
embryogenesis .
All endoderm) formed
germ layers ( ectoderm ,
tissues are derived from three initial mesoderm
,
cells to
via
gastrulation during embryonic development the
embryo from blastula
single layer of
→
.
process that
changes a with a
containing multiple layers of cells .
In chordates flexible notochord will develop during formation
,
a
gastrulation and lead to the
subsequent
of a neural tube .
The formation of a neural tube in
embryonic chordates occurs via the process of neurulation .
1 Notochord forms from mesoderm cells after complete
.
soon
gastrulation is .
2.
Signals from notochord cause inward
folding of ectoderm at the neural plate .
3. Ends of neural plate fuse and disconnect to form an autonomous neural tube .
I 2 3
1
Neurulation in a Xenopus Embryo Functions
, Spina Bifida
Closure of a neutral tube does not occur
simultaneously along the entire
length of the
embryo .
↳ The area where the brain forms is well advanced over the caudal 1 tail )
region, where closure occurs more
slowly .
Spina bifida is a birth defect
resulting in the incomplete closure of the neural tube ( it is associated with the vertebrae )
It is found in the lumbar and sacral where closure is
areas →
regions slowest .
The vertebral
processes do not fuse, leaving the spinal cord nerves exposed and prone to damage .
Trust forward or
laterally
Spina bifida Occult a
.
>
splits in the vertebrae are small
,
does not able the spinal cord does not protrude .
Spina bifida
Cystic a >
meningeal cyst forms which may include the spinal elements .
↳ Extreme cases →
paralysis or bladder dysfunction .
