Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Embryology > Neurulation and Somitogenesis > Flashcards

Neurulation and Somitogenesis Flashcards

1
Q

What is Neurulation

A

Formation of the vertebrate nervous system in embryos

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Explain the process of Neurulation

A

1- Notochord induces formation of CNS by signalling the ectoderm above it to form the neural plate
2- neural plate folds in on itself to form the neural tube
3- neural tube differentiates into the brain and spinal cord
4- neural crest cells derived from neural tube , migrate and form PNS and other structures such as melanocytes and cartilage in head

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is Gastrulation

A

The formation of the 3 embryonic layers : ectoderm , mesoderm and endoderm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the neural plate composed of

A

neuroectoderm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Where does the notochord arise from

A

Mesoderm, arises from the midline & extends to the cranial region

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Where does the neural tube arise from

A

Ectoderm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Explain the development of the Notochord & What Day it would happen

A

Day 15-16

Some Mesodermal cells migrate cranially in the midline of the mesodermal layer and form rod-like notochord process

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

At What Day is the Development of the neural tube

A

Day 21

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Explain in detail the development of the neural tube

A

1- Neuroectodermal tissue will differentiate from ectoderm and thicken into neural plates
2- Neural plate border separates the ectoderm from neural plate via a neural plate border
3- neural plate will bend dorsally with two ends eventually joining at the borders = now called neural crest ( made of neural plate border )
4- Closure of neural tube disconnects neural crest form ectoderm & the neural plate from both the neural crests and the ectoderm
5- Neural crest cells differentiate to form PNS
6- Notochord degenerates and only stays as the nucleus pulpous of intervertebral discs
7- other mesoderm cells differentiate into somites , precursors for axial skeleton and skeletal muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are neural crests cells composed of

A

Neural plate border that has been separated form he neural plate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the function of the notochord

A

It’s an inductive structure that turns the overlying ectodermal tissue around it into neural tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

The region of the ectoderm under the influence of the notochord to turn into neural tissue is called what

A

Neural Plate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Pluripotent neural crest cells migrate and give rise to which nervous structures

A

1- Spinal Ganglia ( dorsal root ganglia )
2- Ganglia of autonomic nervous system
3- Ganglia of some cranial nerves
4- Sheaths of peripheral nerves
5- Meninges of brain and spinal cord
6- Melanocytes
7- Suprarenal medulla ( of the adrenal gland )
8- Skeletal muscular components in the head

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is BMP

A

Bone morphogenetic Protein

- morphogen released by notochord which stimulates changes of ectoderm into neural tissue to make the neural plate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Explain the development of the Somites

A

1- As notochord and neural tube forms a longitudinal column of paraxial mesoderm is also forming
2- Paraxial mesoderm differentiates and divides into paired cuboidal bodies ( somites )
6- By end of Week 5 there is 42-44 pairs of somites

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the somites & what do they form

A

Blocks of mesoderm located on either side of the neural tube that give rise to multiple cell/structures

1- Cartilage of axial skeleton : vertebrae
2- Muscles of rib cage, limbs and back
3- Cells that contribute to connective tissue of dermis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

When the neural tube starts folding where does it start

A

In the midline , then extends cranially and then posteriorly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Which area does the neural tube seal/ fold last

A

The posterior portion of the spinal cord

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the anterior neuropore and posterior neuropore

A

Last regions to close :
anterior will become head
and posterior will develop limbs ( legs )

20
Q

What are the different cells of the somite

A

1- Sclerotome : bone
2- Myotome : muscle
3- Dermatome : connective tissue

21
Q

What embryonic structure makes up the intervertebral disk

A

The notochord , the core of it called nucleus pulpous makes up the intervertebral disk

22
Q

Explain the differentiation within the Somites

A

1- Initially somite is composed of sclerotome and demomyotome cells
2- Sclerotome cells lose their adhesion to each other and migrate leaving dermomyotome cells to divide
3- Myotome muscle cell precursors form beneath epithelial dermatome

23
Q

Sclerotome gives rise to

A

Bone , vertebrae

24
Q

Myotome gives rise to

A

Muscle of back

25
Q

Dermatome gives rise to

A

Connective tissue of dermis

26
Q

What is Teratogenesis

A

prenatal toxicity causing structural or functional defects in embryo or fetus

27
Q

What is Teratogenesis

A

Prenatal toxicity causing structural or functional defects in embryo or fetus

28
Q

What are most common form of congenital abnormalities , when do they arise , what can cause it and what happens

A

Neural tube defects , arise in week 3-4.
Cause : May be due to teratogenic drugs, alcohol ( affects neuroectoderm ) , folic acid.
Neural folds will fail to fuse and form neural tube

29
Q

What is Fetal alcohol syndrome

A

A spectrum of disorders caused by alcohol drinking during pregnancy

30
Q

What is Cranioarachischis

A

complete open brain and spinal cord

31
Q

What is Anencephaly

A

Open brain and lack of skull vault

32
Q

What is Encephalocele

A

Herniation of the meninges and brain

33
Q

What is important in a women’s diet when pregnancy that is vital for neural tube folding ( used for energy for the process )

A

Folic acid

34
Q

What is Iniencephaly

A

Occipital skull and spine defects with extreme retroflexion of the head

35
Q

What is the most common neural tube fusion defects

A

Posterior neuropore opening = spina bifida

anterior neuropore opening = brain opening

36
Q

What is Spina Bifida ( include different types )

A

Failure of fusion of vertebrae arches or neural tube to close.

Spina Bifida Occulta : failure for vertebrae arches to close but neural tube is still closed& intact

Spina Bifida Cystica : cyst forms and it effects neural tube , neural tube not closed properly

Spina Bifida Myelomeningocele : severe form of Cystica where cysts causes spinal cord displacement

37
Q

What is the mildest for of Spina Bifida and why

A

Spina Bifida Occulta: split in vertebrae doesn’t cause SC or meninges herniation. Asymptomatic.

38
Q

Explain difference between Spina Bifida Cystica Meningocele or Spina Bifida Cystica Myelomeningocele

A

Meningocele : Cyst protrudes to outside and neural plate is open to outside but spinal cord may be still intact , and inside the body ( no displacement )

Myelomeningocele : cysts protrudes outside of body and the spinal cord is displaced and also protruding outside of body . This causes brainstem and part of the maybe cerebellum to be pulled down and forced through the skull . This blocks the pathway of CSF drainage

39
Q

What condition is often associated with Spina bifida

A

Hydrocephalus as CSF drainage will be blocked.

40
Q

What is the most serious form of Brain congenital defect

A

Anencephaly Where cerebral hemispheres and cerebellum are absent

41
Q

How could neuro Congenital defects be helped

A

Via Folic acid during pregnancy

42
Q

What is Encephaloceles

A

Protrusion of the brain and meninges through openings in the cranial vault

43
Q

Difference between Cranial Meningocele and Cranial Encephalocele

A

Meningocele : meningeal sac protrudes form head

Encephalocele : meningeal sac , cerebral cortex, cerebellum , and brain stem protrude from head

44
Q

What is the prognosis of Spina Bifida Myelomeningocele

A

Could have successful closure but there is a risk of infection and if any survives after proper closure then risk ( usually results in ) of stationary disability

45
Q

Hairy patch or other skin cage on back might make you suspect what

A

Spina Bifida Occulta

46
Q

What is Spina Bifida Dysraphism

A

Deficiency of atleast 2 vertebral arches that could be covered by a lipoma

Embryology (4 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions