NEURULATION Flashcards
It is the result of thickening of the surface ectodermal cells
NEURAL PLATE
When neural plate bwcomes depressed it forms?
NEURAL GROOVE
and the edges of the neural plates becomes raised or elevated to form the?
NEURAL FOLDS
neural plate converge and fuse dorsally to form the? with a?
NEURAL TUBE w/ a NEURAL CANAL & NEUROEPITHELIUM
neural plate converge and fuse dorsally to form the? with a?
NEURAL TUBE w/ a NEURAL CANAL & NEUROEPITHELIUM
Bilaterally, where the neural groove is joined to non-neural ectoderm, neural ectodermal cells detach as the neural fold FUSE, PROLIFERATE & ASSUME a position dorsolaterally to the neural tube to form the??
NEURAL CREST CELLS
when neural crest cells migrate DORSALLY they become??
pigment of skin
when neural crest cells migrate VENTRALLY they become?
NEURONS OR GLIAL CELLS OR ADRENAL MEDULLA CELLS
and those in head region forms?
MESENCHYME (ectomesenchyme)
during head process, it occupies the??
Anterior border of future head
it is bounded by the crescentic head fold or??
subcephalic pocket
this space separates the head process from the embryonic disk?
SUBCEPHALIC SPACE
HEAD PROCESS IN CODES
- Occupies the A.B of future head
- BOUNDED by the sucephalic pocket
- SUBCEPHALIC SPACE separates the head process
- cylindrical head process ELONGATES
- elongation INCORPORATES the most anterior half dozen somites into the future head
head process in humans occurs at what days of embryo?
18 DAYS
head process in chick embryo occurs at how many hours of incubation?
20-22 hours
it;s the beginning of the formation of the definitive embryonic body.
Cephalic growth
2 succeding events in cephalic growth.
- formation of sucephalic pocket
- Lateral body folds
transveres-furrow is called
SUBCEPHALIC POCKET
lateral-furrow on both side of head process is called?
Lateral body folds
the first part of the gut tube that is formed is the?
FOREGUT
most rostral tip entually becomes the?
PHARYNX
most rostral tip entually becomes the?
PHARYNX
foregut is formed when?
SUBCEPHALIC expands caudally beneath the head process
when these 2 meets in the ventral & midline & and then fuse forming the floor of the foregut.
LEFT AND RIGHT ENDODERMAL FOLDS
When folding continues caudally to the level of the umblicus & later a new endodermal enfolding starts at the tail region to form the?
HINDGUT
These are blocks of mesoderm
SOMITES
These are blocks of mesoderm
SOMITES
somites is derived from?
PARAXIAL MEDOSERM
somites formation starts at the middle of the 1/3 embryonic disk during?
20th hour
by this hour the first pair of somite is completed
21st hour
how many interval is given until the 4oth hour?
1 hour interval
it accumulates on each side of the notochord and is designated as paraxial mesoderm?
MESODERM
Cells of paraxial mesodeem becomes COMPACT and ARRANGED radially round a tiny cavity called ?
MYOCOELE
from PROLIFERATION of local mesenchyme laterl=al to cranial end of the notochord developed the ?
OCCIPTAL SOMITES
Rostral to the notochord, mesenchyme forms less-developed somites called?
SOMITOMERES
at about this hours of incubation in chick embryo the 36 pairs of somites is complete
72
this is lateral regions of somites, that migrate to form the skin dermis ?
DERMATOME
Skin epidermis, hair follicle and glands are derived from?
SURFACE ECTODERM
when neural crest cell migrate into the epidermis it becomes the?
MELANOCYTES & TACTILE DISC RECEPTORS
this is the medial region of somites that forms the most of AXIAL SKELETON
SCLEROTOME
this is the middle region of somites that forms the skeletal musculature?
Myotome
cardiac tube originates from?
PAIRED PRIMORDIA in the mesoderm
at this hour of incubation, Mesenchymal cells in the cardiogenic plate MIGRATE between the lateral ENDODERM and CARDIOGENIC PLATE and form several SMALL ENDOCARDIAL VESICLES that eventually COALESCE
25 HOUR OF INCUBATION
