Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Sem3 > Case 1 > Flashcards

Case 1 Flashcards

(65 cards)

Start Studying
1
Q

When does gastrulation begin?

A

3rd week of embryology

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

What triggers the start of gastrulation?

A

Formation of primitive streak and primitive node (cranial end)

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

What is gastrulation?

A

Formation of trigeminal gastrula - ectoderm, mesoderm, endoderm

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

What is does each trigeminal gastrulation layer form?

A

Surface Ectoderm- epidermis,hair, nails, lens of eyes

Mesoderm- muscle, bones, cartilage, adipose tissue, circulatory system

Endoderm- colon,stomach,bladder, pancreas

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

What is the prechordal plate?

A

Thickening of the hypoblast and epiblast; forms the mouth and helps to determine cephalic from caudal end

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

What is the notochord?

A

Layer of cells from primitive node that forms between the ectoderm and endoderm, and surrounded by mesoderm

It signals the formation of ectoderm neural plate

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

What does the notochord form?

A

Nucleus pulposus

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

When does neurulation begin?

A

Day 22

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

What happens during neurulation?

A

Neural plate forms > neural groove > neural folds elevate to fuse > neural tube

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

When does the anterior and posterior neuropores close?

A

Day 24/25 and 27/28

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

What are neural crest cells?

A

Cells from the neural folds that go on to make a range of body cells - PNS, adrenal medulla, and dentin of teeth

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

What are Somites?

A

Form from mesoderm along the length of neural tube from rostral to caudal end

Total of 44pairs

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

What do somites form?

A

Vertebrae, ribs, skeletal muscles, dermis, cartilage and tendons

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

What are the 3 primary vesicles?

A

Prosencephalon, Mesencephalon, Rhombencephalon

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

What are the three flexures?

A

Cephalic, Pontine and cephalic flexures

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

What are the secondary vesicles?

A

Prosencephalon - Telencephalon (cerebrum, basal ganglia and hippocampus) and Diencephalon (thalamus, uvea, retina)

Mesencephalon - mesencephalon (midbrain)

Rhombencephalon - Metencephalon (cerebellum + pons) and myelencephalon (medulla)

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

What is the development of the spinal cord?

A

Neural tube > neuroepithelial cells > neuroblast form mantle layer - grey matter > marginal cells form white matter cells

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

What divides the alar and basal plate?

A

Sulcus limitans

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

Where do the neural crest arise?

A

Dorsal neural tube along the whole length of spinal cord

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How do neuronal migration in PNS occur?

A

Neuroepithelial cells express Snail1/2 > repress adhesion molecules > epithelial to mesenchymal transition > mesenchymal to destination and cease Snail1/2 expression

This is guided by somites

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

How is a Dorsoventral Axis developed?

A

TGF-beta (BMP) and SHH morphogens gradient

TGF - dorsal neural tube and SHH notochord and floor plate

The gradients activates Transcription factors that regulate differentiation of sensory and motor neurons

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

How is an Anterior-Posterior Axis Developed?

A

Retinoic acid from somites into anterior acid of neural tube (cephalic end)

FGF from stem zone cells into posterior axis of neural tube (caudal end)

Gradient of these two leads to different cell differentiation from the middle (anterior differentiate - posterior undifferentiated)

homeotic genes (HOX) express in clusters and the combination of genes determines the identity of block of tissue

Shh and FGF set up left and right hemisphere, brain and brain stem

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

What is neurogenesis?

A

Differentiation of progenitor cells into their programmed cells

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

How does the progenitor cell know which is apical and basal end?

A

Par complex at the tip of the cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What are the two type of progenitor cell division?
Symmetrical = 2 daughter progenitor cells Assymmetrical = 1 daughter progenitor and 1 neuronal cell
26
What does Shh do in neurogenesis?
It’s a mitogen for proliferation of progenitor cells
27
What does differentiated progenitor cells cleave to migrate?
Primary cilium
28
What is periventricular heterotropia?
Cluster of neurons forming in nodules that can’t be correctly placed formed from primary cilium not clearing properly - leads to seizures, mild intellectual disabilities, brain malformation, microcephaly, delayed development
29
What is a neural tube defect?
Failure of neural tube closure
30
What is the epidemiology of NTD?
1.2 per 1000 births anencephaly is 40% SB 40%
31
What are the environmental factors linked with NTDs?
Diabetes | Lack of Folic Acid
32
What is the recommended intake of folic acid to prevent NTD?
Natural occurring Folinic Acid + THF First occurrence= 400microgram daily before conception and 12wks during pregnancy Recurrence= 4-5milligram per day
33
How do you diagnose NTD?
Increase in maternal serum alpha-fetoprotein (AFP) with amniocentesis during 16-18wks [you can also measure acetylcholinesterase] Ultrasonography for mother’s at risk To locate lemon sign - anencephaly detected from 12wk - SB detected from 16-20wks
34
What is a lemon/banana sign?
Ultrasound features of Arnold-Chiara Malformation in foetuses with open NTD ``` Lemon= scalloping of frontal bone Banana= caudal displacement changes cerebellum shape ```
35
What causes LEMON sign?
Low intracranial pressure due to downward shift of brain in SB causing frontal bone to flatten or scallop inward Disappears with growth of foetus - frontal bone strengthens Only present up to 24wks
36
What is the Arnold-Chiara Malformation?
Distortion of base of the skull with protrusion of lower brain stem and part of the cerebellum through foramen magnum
37
What are the four types of Arnold-Chiara Malformation?
Type 1: herniation of cerebellar tonsil and medulla through foramen Magnum Type 2: herniation of cerebellar vermis, brain stem and fourth ventricle below foramen magnum (linked to myelomeningocele and hydrocephslus) Type 3: herniation of entire posterior fossa contents and brain stem into a cervical encephalocele Type 4: cerebellar hypoplasia
38
How is ACM treated?
Type 1&2 = posterior fossa decompression surgery to relieve pressure on spinal column and create space for cerebellum
39
What is a lumbar puncture?
It is drawing out of CSF from L4-L5 (use posterior iliac crest line) First conduct CT to check there is no intracranial hypertension to prevent herniation
40
What is anencephaly?
Partial or complete absence of bone of rear skull, meninges, and cerebral hemispheres of the brain
41
What is cephalocele?
Herniation of cranial contents through skull defects Cranial meningocele, encephalocele, ventriculocele
42
What is Holoprosencephaly?
Prosencephalon failing to divide into Telencephalon and Diencephalon due to SHH gene defect
43
What is Spina Bifida?
Lack of close of posterior neuropore SB Occulta - open vertebrae arch with no external lesion SB cystica - meningocele or myelomeningocele
44
Where does SB occulta occur mostly?
L5 and S1 w/ patch of hairy skin, dimple
45
What is myelomeningocele?
SB with spinal cord and nerve roots exposed in lesion causing paralysis of legs (higher lesion =more severe) Lumbrosacral in 80% and 90% complicated by hydrocephalus
46
What is meningocele?
Protrusion of méninges without neural tissues 5% of SB
47
What is hydrocephalus?
Accumulation of CSF in the intracranial cavity caused by excess CSF prod, decrease reabsorption via arachnoid granulations and obstruction of flow in ventricle system
48
What are the symptoms of Hydracephalus?
Headache, nausea, vomiting, cognitive impairment, decreased vision, CN VI palsy (can’t abduct properly) and anterior fontanelle bulge Treatment = ventriculostomy, ventriculoperitoneal shunt
49
What is Bipolar Disorder?
Mental illness characterised by periods of elevated mood (mania) and depression
50
What are the two types of Bipolar Disorder?
Type I: mania alternating with depressive episodes Type II: one hypomania period and one major depressive episode in a lifetime (depression period is predominant and can be mistaken for MDD)
51
What is the Epidemiology of Bipolar Disorder?
* 2.4% life time prevalence * 1.1:1 ratio M:F * Any age onset (BD1 = 18; BD2= mid-20s) * life expectancy = reduced by 9-20yrs * suicide risk 15x bigger than population (10-15% die by suicide) * comorbid disorders: anxiety disorder in 75%; ADHD; drug and alcohol misuse in 60%
52
What are the symptoms of Mania?
Last at least 1wk 3 or more: inflated self esteem, decreased need for sleep, pressure of speech, racing thoughts, distractibility, goal-directed and high risk/painful consequence activity Cause impairment in social or occupational function and may need hospitalisation
53
What is Hypomania?
Last at least 4 consecutive days 3 or more of: inflates self-esteem, highly irritable, distractibility, decrease need for sleep, pressure of speech, racing thoughts, increase goal-directed and high pain/risk consequence activities Doesn’t cause impairment in social or occupational functioning or need to hospitalise Improve productivity
54
What is the Aetiology of Bipolar Disorder?
Genetics: 70% heriditability; genes involved in calcium and sodium voltage channels, NMDA receptors, insulin secretion regulation [Type I linked with SCHZ and II with MDD] Environmental: stress and loss, medications (corticosteroids, L-Dopa, thyroid hormones, MAO-I/TCAs, antidepressants - lead to Mania), substance misuse, AIDs, Epilepsy, Head injury, MS, hypothyroidism, CVD,
55
What is the link between Bipolar and Dopamine?
Increase DA synthesis in striatum (all subdivisions) leading to psychotic symptoms
56
How are the different phases of Bipolar Disorder treated?
Acute Mania: antipsychotics - olanzapine, risperidone, quetiapine; antiepileptic- Valproate and Carbomazepine; mood stabiliser - Lithium Acute MD phase: don’t give antidepressants; antiepileptic- Lamotrigine; antipsychotic - quentiapine (low dose); Lithium Maintenance Phase: prophylaxis - Lithium, Olanzapine and Valproic Acid (prevents mania)
57
Why are other antipsychotics not good for maintenance?
Because they only protect against mania
58
What is the mechanism of Lithium?
Administered in a salt (carbonate or citrate) It’s mechanism is not completely understood Rapidly absorbed by the upper GIT and 95% is excreted by kidney It increase serotonin and GABA neurotransmission and decrease Glutamate and Dopamine
59
What are side effects of Lithium
Fine tremor (give propranolol - Beta Blocker), Weight gain, nephrogenic diabetes insipidus(NDI) Long-term leads to hypothyroidism and Kidney problems (especially in women under 60y and people with high lithium blood conc.)
60
What is the MOA of Valproate?
Increases GABA neurotransmission - depress Sodium voltage gated channels, inhibits GABA transaminase, and glutamate formyl transferase
61
Side effects of Valproate?
Nausea, tremor, weight gain, folate antagonist - increasing likelihood of NTDs
62
How do antipsychotics work?
Block D2 receptors and serotonin receptors reducing over activity of Mesolimbic and mesocortical pathways
63
What are the NS cells
CNS: Ependymal - line ventricles and central canal; secrete, circulate and monitor CSF Microglia- remove debris (phagocytosis) Astrocytes- BBB, structural support, absorb and recycle neurotransmitters, form scar tissues after injury Olingocytes- myelinate CNS neurones Schwann cells- myelinate PNS neurones Satellite cells- surround neurone cell bodies in ganglia; regulate nutrient and neurotransmitter leaves around neurones in ganglia
64
What is the Abortion Act 1967?
2 practitioners can agree to terminate pregnancy if: - doesn’t exceed 24wks and continuation causes risk to mother or family - termination prevents risk to mother - termination prevents risk to child - after 24wks IG prevents harm to mother or child being seriously handicapped
65
What is the different level of consent?
Under 16: Gillick competent 16-17: family Act 1969

Sem3 (10 decks)

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