Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Fundamentals of neuroscience > Neurodevelopment (anatomy) > Flashcards

Neurodevelopment (anatomy) Flashcards

(71 cards)

Start Studying
1
Q

Why is it so important that the brain devleops properly?

A

The brian is made up of:
- Neurones = 10^11 (100bn)
- Glial cells = 10^12
- Synapses = 10^14

Thereofre it is very complex w lots of networks so is important it devleops right

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

What are the 2 divisions of development of the nervous system?

A
  1. Anatomical development
  2. Cellular development
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What happens during anatomical devleopment of the NS?

A
  • Formation of the neural tube
  • Neural crest cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What happens during cellular devlopment of the NS?

A
  • Generation of new cells
  • Migration of cells
  • Making connections
  • Death of cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What happens when sperm fertilises the egg?

A

There is a massive cell division that occurs

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

What happens around 11-15 days in the embryo?

A

At this point it consists of the 3 important layers for development:
- Endoderm
- Mesoderm
- Ectoderm

These 3 layers go on to form all the different organs of the body

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

What does the endoderm go on to form?

A

Form the cells that line our internal organs

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

What does the mesoderm go on to form?

A

Muscle, bone & the immune system

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

What does the ectoderm go on to form?

A

The NS - also the epidermis

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

What are the 3 main stages in neurulation?

A
  1. Formation of the neural plate
  2. Formation of the neural folds & neural groove
  3. Closure of neural folds forming neural tube & migration of neural crest cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is neurulation?

A

The formation of the neural tube from the notochord

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

What is the entire process of forming the neural tube?

A
  • During neurulation the notochord (part of mesoderm) starts to send out signals
  • Signals form notochord stimulate the differentiation of the cells of the neuroectoderm into the NEURAL PLATE (an elongated sheet of cells)
  • As development continues, the neural plats starts to fold in on itself - creates NEURAL GROOVE
  • Neural folds are on the side of the groove, they fuse to the top to form the neural tube –> will go on to form the anatomicla part of the CNS
  • Few cells at the tips of the neural folds called the neural crest cells don’t form into the tube & leave –> migrate to form the PNS
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What do the cells on top of the neural tube form?

A

On top we get the remaining ectoderm which will formt the epidermis (skin)

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

How does the neural tube join up?

A

It doesn’t happen simultaneously all the way along

The join starts at the neck region & will progress rostrally (up to brain) and caudally (spinal cord) to close the structure

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

What do the anterior (rostral) and posterior (caudal) ends of the neural tube form?

A

Anterior = brain

Posterior = spinal cord

Fuses halfway between the brain and moves either way to properly join the neural tube

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

What happens to the anterior part of the neural tube before 4 weeks?

A

(The brain)

We get further differentiation from it being a tube structure

It differentiates into swelling (vesicles) & this is what forms the anatomical divisions of the brain & give it its structure

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

What happens to the posterior part of the neural tube at 4 & 6 weeks?

A

(Spinal cord)

Posterior pretty much remains the same

It is a tube structure which makes sense as it goes on to form the spinal cord which appears as a long tube

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

What happens to the anterior part of the neural tube between 4-6 weeks?

A

(Forming the brain)

Around 4 weeks = Differentiates into 3 parts; forebrain, midbrain & hindbrain

6 weeks = development cont. –> we get furhter differentiation of the fprebrain vesicles

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

What are the further vesicular divisions of the forebrain at 6 weeks?

A
  • Telencephalic vesicles
  • Diencephalon
  • Optic vesicles
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What do the telencephalic vesicles turn into?

A

Cerebral hemispheres

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What does the diencephalon turn into?

A

Thalamus & hypothalamus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What do the optic vesicles turn into?

A

Optic nerve & retinal (eye)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Why are the optic nerves and olfactory bulb considered more CNS than PNS compared to other cranial nerves?

A

They sproud directly from the brain tissue, os they are jsut an extension of this –> making them more CNS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

After 6 weeks how does the shape of the brain change?

A

As developemnt goes further, the cerebral hemispheres swell both POSTERIORLY (backwards) & LATERALLY (around the side of the brain)

This envelopes the diencephalon

We get a sprouting of olfactory bulbs from the ventral side as well

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
After the diencephalon forms the thalamus & hypothalamus what happens to it?
It ends up just touching the sub hemisphere of the brain once it's fully developed
26
What happens to the neural crest cells that do not form the neural tube?
They migrate away to form: - The PNS - The enteric NS - Cells of the skin (melanocytes) - Parts of the skull
27
What are the 2 neural tube defect diseases?
- Spina bifidia - Anecephaly
28
What is spina bifidia?
- Failure of neural tube in the spinal cord to fuse - Most common in lower back = lumbosacral region - Paralysis below this region
29
What is anencephaly?
- Failure of neural tube in brain region to fuse - Incompatible with postnatal survival
30
What is the treatment for neural tube defects?
Folate supplement for pregnant women --> mechanism unclear
31
What happens if the neural crest cells fail to migrate?
Causes Hirschsprug's disease
32
What is Hirschsprung's disease?
- Failure of neural crest cells to migrate to large intestine (colon) - No autonomic NS innervation of the large intestine - Means no peristalsis at a point in the gut - no movement of contents, causes build up - Constipation
33
What is the treatment for Hirschsprung's disease?
Surgery to bypass or remove diseased part of the colon
34
What does the lumen of the neural tube form?
Forms brain ventricles - where CSF flows through
35
What is the subventricular zone?
- Region adjacent to the lumen of the neural tube - Contains neural stem cells = neuroepithelial cells - Produces neurones & glial cells (divide via mitosis)
36
What are the 3 types of neurones?
- Sensory - Motor - Inter
37
How is it determined what type of neurone it will become?
It is determined by their exposure to different proteins at different concentrations when being formed in the subventricular zone of the neural tube
38
What are the 2 important proteins involved in determining what type of neurone a neurone becomes?
- Bone Morphogenic Protein (BMP) - Sonic Hedgehog (SHH) protein The conc of these in each area of the tube determines the type of neurone
39
What sort of neurones are made in the dorsal vs ventral area of the neural tube?
Dorsal = makes sensory Ventral = makes motor
40
Which cells in the neural tube produce Bone Morphogenic Protein (BMP)?
Cells on the roof plate (dorsal) of the neural tube (make sensory neurones) Once produced diffuses down the side of the neural tube
41
Which cells in the neural tube produces Sonic Hedgehog (SHH) protein?
Cells in the floor plate (ventral) of the neural tube (makes motor neurones) Once produces can diffuse thru neural tube
42
Where in the neural tube are interneurones produced?
In the middle, they are produced around the hlaf way point where the hormones SHH and BMP diffuse close enough
43
What are the two things that can go wrong with neurone production?
Reduced cell proliferation caused by environmental insults OR Uncontrolled cell proliferation (So it is important that the production of the cells is controlled & regulated to prevent these)
44
What can reduced cell proliferation caused by environmental insults cause?
- Toxins e.g. sodium valproate - Infections agents e.g. rubella - Undernutrition - Maternal inflammation - Neurodevelopmental disorders e.g. autism, schizophrenia
45
What can uncontrolled cell proliferation cause?
Childhood brain cancer
46
What is symmetrical division?
1 radial glial cell ---> divides into 2 glial cells
47
What is asymmetrical division?
1 radial glial cell --> divides into 1 radial glial cell & 1 neuron
48
How are neurones produced from a glial cell?
- Neuroepithelial cells divide, they differentiate into radial glial cells - Radial glial cells can divide, initially symetrically into 2 glial cells - Eventually their division becomes asymmetrical & produce a glial cell & a neurone - Fate is determines by hormones BMP and SHH
49
What do the glial cells produced by symmetrical division turn into?
- Can differentiate into other glial cells e.g. astrocytes OR - They can act as scaffolding for neurones to grow
50
How can glial cells act as scaffolding for neurones?
They have rlly long processors from the subventricular zone all the way to the top of the brain Neurones produced during this division can use the scaffolding & migrate to other areas in the brain
51
How many layers doe the cortex have & how are they structured?
6 layers - formed from the bottom upwards Outer layer = 1 Innermost layer = 6
52
Where in the brain is migration of neurones particularly important?
The cortex, as it has many layers which are carefully arranged Migration allows the neurones to get to the correct layer
53
What can cause improper formation of the cerebral cortex?
failure of cell migration
54
What can failure of cell migration in the cerebral cortex lead to?
- Incorrect layering - Which can cause some types of epilepsy
55
What are neurites?
Processors that neurones send out for growth Have growth cones on the end of these
56
What is the growth cone?
Found on the end of neurites They are able to move thru the extracellular environment & navigate towards its target neurone Extends the neurite behind it
57
What allows the growth cone to move?
Protein-protein interactions Proteins expressed on the growth cone: - Laminin of the extracellular matrix - Integrins expressed by growth cone
58
What attracts the growth cone to its target?
Guidance cues Different growth cones express different detectors of different guidance cues
59
What are the types of guidance cues?
- Chemoattractant - Chemorepellent
60
What happens once the growth cone reaches its target?
A synapse is formed
61
What are the 2 main methods of cell death?
- Competition for tophic factors - Synaptic rearrangement
62
What are the 2 main trophic factors that neurones are in competition for?
- Nerve Growth Factor (NGF) - Brain Derived Neurotrophic Factor (BDNF)
63
What is the action of trophic factors?
They are released from postsynaptic neurones & bind to receptors on presynaptic neurone
64
How do trophic factors help cells?
They inhibit programmed cell death (apoptosis)
65
How are trophic factors used to control the amount of neurones?
We produce a lot more neurones in the brain than we need --> excess need to be removed via apoptosis Competition for trophic factors is high --> those which cannot get them will go through apoptosis
66
What happens during synaptic rearrangement?
- It refines synaptic connections - Those that are active have more connections --> those who are less active will have their connections cut
67
When does synpatic rearrangment happen most?
During childhood This is why early childhood experiences are so important as they determine which connections are cut
68
When is the production of glial cells at its most?
In the first 2 years
69
When does formation of synapses peak?
At 2 years --> when 2,000,000 new synapses per second are forming
70
How long does mylenation happen for?
Continues into your 20s and 30s This is the oligodendrocytes essetially generating the optimum conduction velocity
71
How can extreme neglect at a young age affect brain development?
It can have a severe effect on neurodevelopment as it is essentially changing the structure of the brain (Key stage in glial formation & synapse formation happens in the first 2 years)

Fundamentals of neuroscience (38 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions