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AN79.1-6 | 3rd to 8th week of development — Glossary

Glossary — 3rd to 8th week of development

Key terms introduced in this module, in order of first appearance. Use this as a revision checklist.

TermWhere Introduced
Neural tube defects (NTDs)relevance
Sacrococcygeal teratomarelevance
Nucleus pulposusrelevance
NMC 2024 CBMErelevance
Folic acid policyrelevance
bilaminar discrecall
amniotic cavityrecall
primary yolk sacrecall
Teratogensrecall
The Primitive StreakPart 1: Primitive Streak — Formation and Fate (AN79.1)
Formation (Day 14–15, 3rd week):Part 1: Primitive Streak — Formation and Fate (AN79.1)
caudal midlinePart 1: Primitive Streak — Formation and Fate (AN79.1)
Cranial–caudal axisPart 1: Primitive Streak — Formation and Fate (AN79.1)
Left–right axisPart 1: Primitive Streak — Formation and Fate (AN79.1)
Dorsal–ventral axisPart 1: Primitive Streak — Formation and Fate (AN79.1)
Structure:Part 1: Primitive Streak — Formation and Fate (AN79.1)
Primitive streakPart 1: Primitive Streak — Formation and Fate (AN79.1)
Primitive node (Hensen's node)Part 1: Primitive Streak — Formation and Fate (AN79.1)
Primitive groovePart 1: Primitive Streak — Formation and Fate (AN79.1)
Primitive pitPart 1: Primitive Streak — Formation and Fate (AN79.1)
Gastrulation — The Process:Part 1: Primitive Streak — Formation and Fate (AN79.1)
intraembryonic mesodermPart 1: Primitive Streak — Formation and Fate (AN79.1)
EctodermPart 1: Primitive Streak — Formation and Fate (AN79.1)
MesodermPart 1: Primitive Streak — Formation and Fate (AN79.1)
EndodermPart 1: Primitive Streak — Formation and Fate (AN79.1)
gastrulationPart 1: Primitive Streak — Formation and Fate (AN79.1)
trilaminar discPart 1: Primitive Streak — Formation and Fate (AN79.1)
Fate of the Primitive Streak:Part 1: Primitive Streak — Formation and Fate (AN79.1)
disappears entirelyPart 1: Primitive Streak — Formation and Fate (AN79.1)
Clinical Significance:Part 1: Primitive Streak — Formation and Fate (AN79.1)
80% benign at birth; becomes malignant if not excised earlyPart 1: Primitive Streak — Formation and Fate (AN79.1)
Situs inversusPart 1: Primitive Streak — Formation and Fate (AN79.1)
Conjoined twinsPart 1: Primitive Streak — Formation and Fate (AN79.1)
The NotochordPart 2: Notochord — Formation and Fate (AN79.2)
Formation (Days 16–22, 3rd week):Part 2: Notochord — Formation and Fate (AN79.2)
notochordal processPart 2: Notochord — Formation and Fate (AN79.2)
notochordPart 2: Notochord — Formation and Fate (AN79.2)
oropharyngeal membranePart 2: Notochord — Formation and Fate (AN79.2)
cloacal membranePart 2: Notochord — Formation and Fate (AN79.2)
Functions of the Notochord:Part 2: Notochord — Formation and Fate (AN79.2)
Defines the central axisPart 2: Notochord — Formation and Fate (AN79.2)
Induces neurulationPart 2: Notochord — Formation and Fate (AN79.2)
neural platePart 2: Notochord — Formation and Fate (AN79.2)
Determines vertebral body formationPart 2: Notochord — Formation and Fate (AN79.2)
Fate of the Notochord:Part 2: Notochord — Formation and Fate (AN79.2)
surrounded and incorporatedPart 2: Notochord — Formation and Fate (AN79.2)
intervertebral discPart 2: Notochord — Formation and Fate (AN79.2)
persists and expandsPart 2: Notochord — Formation and Fate (AN79.2)
annulus fibrosusPart 2: Notochord — Formation and Fate (AN79.2)
sciaticaPart 2: Notochord — Formation and Fate (AN79.2)
L4–L5 disc prolapsePart 2: Notochord — Formation and Fate (AN79.2)
L5–S1 disc prolapsePart 2: Notochord — Formation and Fate (AN79.2)
ChordomaPart 2: Notochord — Formation and Fate (AN79.2)
clivusPart 2: Notochord — Formation and Fate (AN79.2)
sacrococcygealPart 2: Notochord — Formation and Fate (AN79.2)
Neurulation (3rd–4th weeks)Part 3: Neurulation — Formation of the Neural Tube (AN79.3)
neural tubePart 3: Neurulation — Formation of the Neural Tube (AN79.3)
Steps:Part 3: Neurulation — Formation of the Neural Tube (AN79.3)
Neural plate induction (Day 18):Part 3: Neurulation — Formation of the Neural Tube (AN79.3)
Neural folds (Day 20–22):Part 3: Neurulation — Formation of the Neural Tube (AN79.3)
neural foldsPart 3: Neurulation — Formation of the Neural Tube (AN79.3)
neural groovePart 3: Neurulation — Formation of the Neural Tube (AN79.3)
Neural tube closure (Days 22–26):Part 3: Neurulation — Formation of the Neural Tube (AN79.3)
mid-cervical regionPart 3: Neurulation — Formation of the Neural Tube (AN79.3)
Anterior (cranial) neuropore closes on Day 25Part 3: Neurulation — Formation of the Neural Tube (AN79.3)
Posterior (caudal) neuropore closes on Day 27Part 3: Neurulation — Formation of the Neural Tube (AN79.3)
Neural crest cellsPart 3: Neurulation — Formation of the Neural Tube (AN79.3)
Neural Tube → CNS:Part 3: Neurulation — Formation of the Neural Tube (AN79.3)
Neural Crest Cells (the 4th germ layer):Part 3: Neurulation — Formation of the Neural Tube (AN79.3)
AnencephalyPart 3: Neurulation — Formation of the Neural Tube (AN79.3)
Spina bifida occultaPart 3: Neurulation — Formation of the Neural Tube (AN79.3)
MeningocelePart 3: Neurulation — Formation of the Neural Tube (AN79.3)
MyelomeningocelePart 3: Neurulation — Formation of the Neural Tube (AN79.3)
EncephalocelePart 3: Neurulation — Formation of the Neural Tube (AN79.3)
Chiari II Malformation (Arnold-Chiari):Part 3: Neurulation — Formation of the Neural Tube (AN79.3)
Prevention of NTDs:Part 3: Neurulation — Formation of the Neural Tube (AN79.3)
Periconceptional folic acid (0.4–5 mg/day)Part 3: Neurulation — Formation of the Neural Tube (AN79.3)
Somite FormationPart 4: Somite Development and Intra-Embryonic Coelom (AN79.4)
Paraxial mesodermPart 4: Somite Development and Intra-Embryonic Coelom (AN79.4)
somitesPart 4: Somite Development and Intra-Embryonic Coelom (AN79.4)
Somite timeline:Part 4: Somite Development and Intra-Embryonic Coelom (AN79.4)
Total: 42–44 pairsPart 4: Somite Development and Intra-Embryonic Coelom (AN79.4)
Somite Derivatives (3 components):Part 4: Somite Development and Intra-Embryonic Coelom (AN79.4)
SclerotomePart 4: Somite Development and Intra-Embryonic Coelom (AN79.4)
MyotomePart 4: Somite Development and Intra-Embryonic Coelom (AN79.4)
DermatomePart 4: Somite Development and Intra-Embryonic Coelom (AN79.4)
Note:Part 4: Somite Development and Intra-Embryonic Coelom (AN79.4)
Resegmentation:Part 4: Somite Development and Intra-Embryonic Coelom (AN79.4)
Intra-Embryonic Coelom (Body Cavity)Part 4: Somite Development and Intra-Embryonic Coelom (AN79.4)
Formation:Part 4: Somite Development and Intra-Embryonic Coelom (AN79.4)
lateral plate mesodermPart 4: Somite Development and Intra-Embryonic Coelom (AN79.4)
Somatic (parietal) mesodermPart 4: Somite Development and Intra-Embryonic Coelom (AN79.4)
Splanchnic (visceral) mesodermPart 4: Somite Development and Intra-Embryonic Coelom (AN79.4)
intraembryonic coelomPart 4: Somite Development and Intra-Embryonic Coelom (AN79.4)
Partitioning of the coelom:Part 4: Somite Development and Intra-Embryonic Coelom (AN79.4)
Pericardial cavityPart 4: Somite Development and Intra-Embryonic Coelom (AN79.4)
Pleural cavitiesPart 4: Somite Development and Intra-Embryonic Coelom (AN79.4)
Peritoneal cavityPart 4: Somite Development and Intra-Embryonic Coelom (AN79.4)
Septum transversumPart 4: Somite Development and Intra-Embryonic Coelom (AN79.4)
Pleuropericardial foldsPart 4: Somite Development and Intra-Embryonic Coelom (AN79.4)
Pleuroperitoneal foldsPart 4: Somite Development and Intra-Embryonic Coelom (AN79.4)
Clinical: Congenital Diaphragmatic Hernia (CDH):Part 4: Somite Development and Intra-Embryonic Coelom (AN79.4)
pulmonary hypoplasiaPart 4: Somite Development and Intra-Embryonic Coelom (AN79.4)
Teratogen-Sensitive Period:clinical_pearl
major structural defectsclinical_pearl
Common teratogens encountered in Indian practice:clinical_pearl
Thalidomideclinical_pearl
Sodium valproateclinical_pearl
Alcoholclinical_pearl
Rubella virusclinical_pearl
CMVclinical_pearl
Retinoic acidclinical_pearl
Diabetes mellitusclinical_pearl
Folic Acid and NTDs:clinical_pearl
posterior neuroporereflection
Primitive Streak (AN79.1):summary
Notochord (AN79.2):summary
Neurulation (AN79.3):summary
Somites and Coelom (AN79.4):summary
Congenital Anomalies (AN79.5):summary

120 terms in this module