Embryology Flashcards
From fertilisation, what is the first clump of cells called?
Morula
What are more than 16 cells called?
Blastocyst
What happens after week 3?
Gastrulation
Trilaminar disc forms
What are the trilaminar disc layers?
Ectoderm
Mesoderm
Endoderm
What is neuralation?
Formation of embryonic NS
What happens in neuralation?
Whats formed?
Ectoderm undergoes differential mitosis
Forms midline groove called neural groove
Groove deepens and forms neural tube
What is also found along the neural tube?
Neural crest cells
What is the function of neural crest cells?
Where are they?
Develop into many cell types
Lateral to neural tube
What do neural crest cells differentiate into?
Brain and CNS
What does the rostral part of the neural tube develop into?
Superior portion
Brain and CNS
How fast does the rostral grow than the caudal?
The rostral part grows faster than the caudal
What does the caudal develop into?
The spinal cord
Inferior portion
What happens by the 5th week of development?
3 primary brain vesicles form
What are the 3 primary brain vesicles?
Prosencephalon (forebrain)
Mesencephalon (midbrain)
Rhombencephalon (hindbrain)
When does further differentiation occur to form the secondary brain vesicles?
By week 7
What does the prosencephalon go into?
Telencephalon
Diencephalon
What does mesencephalon go into?
Stays as mesencephalon
What does rhombencephalon go into?
Metencephalon
Myelencephalon
What part of the brain does telencephalon form?
Cerebral cortex & lateral ventricles
What part of the brain does diencephalon form?
Thalamus, hypothalamus, third ventricles
What part of the brain does mesencephalon form?
Midbrain and aqueduct
What part of the brain does metencephalon form?
Cerebellum, pons and upper part of 4th ventricle
What part of the brain does myelencephalon form?
Medulla oblongata and lower part of 4th ventricle
When does the neural tube close?
At the end of 4th week
What happens in failure for the tube to close in the
Spinal cord
Cephalic region (brain)
Spina bifida
Anencephalus
When is the eye formed?
By week 3
When is there cerebral expansion and commissures?
10 weeks
When is basic structure established?
3 months
When does myelination begin?
5 months
When do lobes cerebrum form?
7 months
When do the gyri/sulci form?
9 months
When do risks of eye malformations take place?
Deafness?
Cardiac malformation?
6th week
9th week
5th to 10th week
