Week 8: Difference between revisions
(New page: Key Events of Human Development during the eight week (week 8) following fertilization.) |
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Key Events of Human Development during the eight week (week 8) following fertilization. | Key Events of Human Development during the eight week (week 8) following fertilization. | ||
== Week 8 == | |||
[[Week 8]] (Clinical Week 10) | |||
{| class="prettytable" | |||
| <center>'''Day'''</center> | |||
| <center>'''Stage'''</center> | |||
| '''Event''' | |||
|- | |||
| <center>50</center> | |||
| Stage 20 | |||
| [[Image:CST20.gif]] | |||
[http://embryology.med.unsw.edu.au/Notes/head.htm Head] scalp vascular plexus visible | |||
[http://embryology.med.unsw.edu.au/Notes/skmus7.htm Limb] upper limbs begin to rotate ventrally | |||
[http://embryology.med.unsw.edu.au/Notes/neuron.htm Neural] amygdaloid body has at least four individual nuclei [http://www.ncbi.nlm.nih.gov/pubmed/2268071 PMID: 2268071] | |||
oculomotor nerve shows a dorsolateral and a ventromedial portion | |||
rhombic lip (rhombencephalon) formation of the cerebellum (intermediate layer) and of the cochlear nuclei | |||
cerebellum cell layer (future Purkinje cells) develops | |||
choroid plexuses of the fourth and lateral ventricles | |||
|- | |||
| <center>51</center> | |||
| | |||
| [http://embryology.med.unsw.edu.au/Notes/git.htm Gastrointestinal Tract] anal membrane perforates | |||
|- | |||
| <center>52</center> | |||
| Stage 21 | |||
| [[Image:CST21.gif]] | |||
[http://embryology.med.unsw.edu.au/Notes/neuron.htm Neural] cortical plate appears in the area of future insula [http://www.ncbi.nlm.nih.gov/pubmed/2252222 PMID: 2252222] | |||
[http://embryology.med.unsw.edu.au/Notes/skmus7.htm Limb] upper and lower limbs rotate | |||
[http://embryology.med.unsw.edu.au/Notes/coelom.htm Intraembryonic Coelom] pericardioperitoneal canals close | |||
|- | |||
| <center>53</center> | |||
| | |||
| | |||
|- | |||
| <center>54</center> | |||
| Stage 22 | |||
| [[Image:CST22.gif]][http://embryology.med.unsw.edu.au/Notes/neuron.htm Neural] neocortical fibres project to epithalamus, to dorsal thalamus, and to mesencephalon [http://www.ncbi.nlm.nih.gov/pubmed/2252222 PMID: 2252222] | |||
[http://embryology.med.unsw.edu.au/Notes/skmus7.htm Limb] fingers and toes lengthen | |||
[http://embryology.med.unsw.edu.au/Notes/nose.htm Sense - Smell] Stage 22 to early fetal period - migratory streams of neurons from the subventricular zone of the olfactory bulb towards the future claustrum [http://www.ncbi.nlm.nih.gov/pubmed/15604533 PMID: 15604533] | |||
|- | |||
| <center>55</center> | |||
| | |||
| [http://embryology.med.unsw.edu.au/Notes/genital.htm Genital ]8 Weeks Testis - mesenchyme, interstitial cells (of Leydig) secrete testosterone, androstenedione | |||
[http://embryology.med.unsw.edu.au/Notes/genital.htm Genital ]8 to 12 Weeks - hCG stimulates testosterone production | |||
[http://embryology.med.unsw.edu.au/Notes/tongue.htm Tongue] Week 8 - nerves penetrate epitheilai basal lamina and synapse with undifferentiated, elongated, epithelial cells (taste bud progenitor cell) | |||
|- | |||
| <center>56</center> | |||
| Stage 23 | |||
| [[Image:CST23.gif]][http://embryology.med.unsw.edu.au/wwwhuman/Stages/Stage23L.htm ]Stage 23 defines the end of the embryonic (organogenesis) period | |||
'''Mesoderm ''' heart prominence, ossification continues | |||
[http://embryology.med.unsw.edu.au/Notes/head.htm Head] nose, eye, external acoustic meatus, eyelids, external ears, rounded head | |||
'''Body '''- straightening of trunk, heart, liver, umbilical cord, intestines herniated at umbilicus | |||
[http://embryology.med.unsw.edu.au/Notes/skmus7.htm Limb] upper limbs longer and bent at elbow, hands and feet turned inward, foot with separated digits, wrist, hand with separated digits | |||
'''Extraembryonic Coelom''' chorionic cavity is now lost by fusion with the expanding amniotic cavity | |||
[http://embryology.med.unsw.edu.au/Notes/neuron.htm Neural] rhombencephalon, pyramidal decussation present, nuclei and tracts similar to those present in the newborn cerebellum present as only a plate connected to midbrain and hindbrain through fibre bundles [http://www.ncbi.nlm.nih.gov/pubmed/2244584 PMID: 2244584] | |||
[http://embryology.med.unsw.edu.au/Notes/skmus8.htm Axial Skeleton] vertebral column 33 or 34 cartilaginous vertebrae (20-33 mm in total length), vertebral pedicles, articular and transverse processes identifiable (no spinous processes) [http://www.ncbi.nlm.nih.gov/pubmed/7216919 PMID: 7216919] | |||
|- | |||
| <center> </center> | |||
| Week 8 | |||
| [http://embryology.med.unsw.edu.au/Notes/git10.htm GIT - Stomach] - Week 8 - Gastrin containing cells in stomach antrum. Somatostatin cells in both the antrum and the fundus. | |||
|} | |||
===Carnegie Stages Link=== | |||
[[Carnegie_stage_1|1]] | [[Carnegie_stage_3|3]] | [[Carnegie_stage_7|7]] | [[Carnegie_stage_8|8]] | [[Carnegie_stage_9|9]] | [[Carnegie_stage_10|10]] | [[Carnegie_stage_11|11]] | [[Carnegie_stage_12|12]] | [[Carnegie_stage_13|13]] | [[Carnegie_stage_14|14]] | [[Carnegie_stage_15|15]] | [[Carnegie_stage_16|16]] | [[Carnegie_stage_17|17]] | [[Carnegie_stage_18|18]] | [[Carnegie_stage_19|19]] | [[Carnegie_stage_20|20]] | [[Carnegie_stage_21|21]] | [[Carnegie_stage_22|22]] | [[Carnegie_stage_23|23]] | |||
===Glossary Links=== | |||
[[A|A]] | [[B|B]] | [[C|C]] | [[D|D]] | [[E|E]] | [[F|F]] | [[G|G]] | [[H|H]] | [[I|I]] | [[J|J]] | [[K|K]] | [[L|L]] | [[M|M]] | [[N|N]] | [[O|O]] | [[P|P]] | [[Q|Q]] | [[R|R]] | [[S|S]] | [[T|T]] | [[U|U]] | [[V|V]] | [[W|W]] | [[X|X]] | [[Y|Y]] | [[Z|Z]] | |||
:Dr Mark Hill 2009, '''''UNSW Embryology''''' ISBN: 978 0 7334 2609 4 - UNSW CRICOS Provider Code No. 00098G | |||
[[Category:Human Embryo]] [[Category:Carnegie Stage]] [[Category:Week 8]] |
Revision as of 12:02, 5 August 2009
Key Events of Human Development during the eight week (week 8) following fertilization.
Week 8
Week 8 (Clinical Week 10)
Event | ||
Stage 20 | File:CST20.gif
Head scalp vascular plexus visible Limb upper limbs begin to rotate ventrally Neural amygdaloid body has at least four individual nuclei PMID: 2268071 oculomotor nerve shows a dorsolateral and a ventromedial portion rhombic lip (rhombencephalon) formation of the cerebellum (intermediate layer) and of the cochlear nuclei cerebellum cell layer (future Purkinje cells) develops choroid plexuses of the fourth and lateral ventricles | |
Gastrointestinal Tract anal membrane perforates | ||
Stage 21 | File:CST21.gif
Neural cortical plate appears in the area of future insula PMID: 2252222 Limb upper and lower limbs rotate Intraembryonic Coelom pericardioperitoneal canals close | |
Stage 22 | File:CST22.gifNeural neocortical fibres project to epithalamus, to dorsal thalamus, and to mesencephalon PMID: 2252222
Limb fingers and toes lengthen Sense - Smell Stage 22 to early fetal period - migratory streams of neurons from the subventricular zone of the olfactory bulb towards the future claustrum PMID: 15604533 | |
Genital 8 Weeks Testis - mesenchyme, interstitial cells (of Leydig) secrete testosterone, androstenedione
Genital 8 to 12 Weeks - hCG stimulates testosterone production Tongue Week 8 - nerves penetrate epitheilai basal lamina and synapse with undifferentiated, elongated, epithelial cells (taste bud progenitor cell) | ||
Stage 23 | File:CST23.gif[1]Stage 23 defines the end of the embryonic (organogenesis) period
Mesoderm heart prominence, ossification continues Head nose, eye, external acoustic meatus, eyelids, external ears, rounded head Body - straightening of trunk, heart, liver, umbilical cord, intestines herniated at umbilicus Limb upper limbs longer and bent at elbow, hands and feet turned inward, foot with separated digits, wrist, hand with separated digits Extraembryonic Coelom chorionic cavity is now lost by fusion with the expanding amniotic cavity Neural rhombencephalon, pyramidal decussation present, nuclei and tracts similar to those present in the newborn cerebellum present as only a plate connected to midbrain and hindbrain through fibre bundles PMID: 2244584 Axial Skeleton vertebral column 33 or 34 cartilaginous vertebrae (20-33 mm in total length), vertebral pedicles, articular and transverse processes identifiable (no spinous processes) PMID: 7216919 | |
Week 8 | GIT - Stomach - Week 8 - Gastrin containing cells in stomach antrum. Somatostatin cells in both the antrum and the fundus. |
Carnegie Stages Link
1 | 3 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23
Glossary Links
A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z
- Dr Mark Hill 2009, UNSW Embryology ISBN: 978 0 7334 2609 4 - UNSW CRICOS Provider Code No. 00098G