Nervous System Development - Quiz 7

Neurulation

formation of basic brain structures

weeks 3-12

Neurulation:

What time frame during pregnancy does it occur?

Neuronogenesis

neurons develop around lateral ventricles; formation of neurons and glia

months 2-4

Neuronogenesis:

What time frame during pregnancy does it occur?

migration

Neurons and glial cells migrate from lateral ventricles to cerebral cortex; cells move to their proper location

months 3-8

Migration:

What time frame during pregnancy does it occur?

month 6 to 1-2 years postnatal

Organization:

What time frame during pregnancy does it occur?

month 8 to early adulthood

Myelinization:

What time frame during pregnancy does it occur?

Gastrulation

an early stage in embryonic development where a simple, single-layered hollow ball of cells (the blastula) reorganizes into a multi-layered structure

endoderm, mesoderm, ectoderm

What are the three germ layers formed during gastrulation?

endoderm

Which germ layer does the below originate from?

Epithelial linings of the respiratory and alimentary tracts

Glands of GI tract

Glands related to liver and pancreas

mesoderm

Which germ layer does the below originate from?

Skeletal muscles

Blood cells

Lining of blood vessels

mesoderm

Which germ layer does the below originate from?

Majority of cardiovascular system

Cartilage

Bones

Tendons

Ligaments

ectoderm

Which germ layer does the below originate from?

Epidermis

CNS

PNS

Eyes

CT of head

neurulation

formation of the neural plate and neural tube

week 3-4

When does neurulation occur during pregnancy?

neural plate

nervous system begins as a longitudinal thickening of the ectoderm - what is it called?

plate, folds, grooves, tube, crest

In what order do the structures formed during neurulation form?

inside the embryo

Where do the neural tube and crest move after formation?

superior neuropore

Which neuropore typically closes by day 27?

inferior neuropore

Which neuropore closes ~3 days after the first one?

ventricles and central canal of spinal cord

What is the cavity of the neural tube a precursor of?

neural tube

What is the precursor for the ventricles and central canal of the spinal cord?

skull and vertebra

What is the anteromedial part of the somite a precursor of?

anteromedial somite

What is the precursor for the skull and vertebra?

skeletal muscle

What is the posteromedial part of the somite a precursor of?

posteromedial somite

What is the precursor for skeletal muscle?

Dermis

What is the lateral part of the somite a precursor of?

lateral somite

What is the precursor for the dermis?

spinal cord and brain

What are the walls of the neural tube a precursor of?

sensory fibers

What is the alar (dorsal) plate a precursor of?

alar plate

What is the precursor for sensory fibers?

motor fibers

What is the basal (ventral) plate a precursor of?

basal plate

What is the precursor for motor fibers?

day 20-35

timing for development of meninges

Meninges

What develops from cells of neural crest and mesenchyme?

neural crest, mesenchyme

What cells serve as the precursors for the meninges?

week 5

timing for CSF development

late fetal into first prenatal year

timing for myelination

day 28

timing for brain formation

week 26-28

timing for gyri formation

midbrain, forebrain, hindbrain

What are the 3 enlargements for brain formation?

myelencephalon, metencephalon

What does the hindbrain enlargement develop into?

upper medulla, pons, cerebullum, fourth ventricle

What does the metencephalon develop into?

lower medulla

What does the myelencephalon develop into?

midbrain, cerebral aqueduct

What does the midbrain develop into?

Telencephalon

What does the anterior forebrain develop into?

cerebral hemispheres, lateral ventricles

What does the telencephalon develop into?

Diencephalon

What does the posterior forebrain develop into?

thalamus, hypothalamus, third ventricle

What does the diencephalon develop into?

neural migration

epithelial cells lining the neural tube divide to produce neurons and glia; do so by sending processes to the brain and pulling themselves to it or by climbing along radial glia

neuronal redundancy

Allows non-damaged parts of the brain to compensate for loss of function when other parts of the brain are damaged

neuronal pruning

Excess neurons and synapses are created during development, what removes the excess that were not strengthened through use?