67 Development of head and neck Flashcards
Where are the bones and autonomic ganglia derived from?
Neural crest of the surface ectoderm;
also contains the connective tissue of head and go pharyngeal arches
Where are the cranial sensory ganglia derived from?
Neural crest and places of the surface ectoderm
What will the neural tube develop into?
Brain and spinal cord;
parasympathetic preganglionic neurons;
optic cup with optic neurons
3 structures from the ectoderm? > form cranial nerves
- Neural crest
- Neural tube
- Placodes
Which of the following are derived from the placodes (ectodermal thickenings in the cranial region)?
Lens and CN1;
inner ear epithelium, CN8 ganglion;
olfactory epithelium
Mesoderm forms part of the cranio-cervical skeleton and _____________?
all muscles
Head muscles are from __________ paraxial mesoderm and prechordal mesoderm.
Unsegmented
_______________ are from segmented paraxial mesoderm.
Tongue and neck muscles
Which of the following are true?
A. Eyes are derived from the prechordal mesoderm
B. SCM and trapezius is derived from the lateral plate mesoderm
C. Pharyngeal arch muscles and tongue muscles are derived from the paraxial mesoderm
All of the above
Fronto-nasal and pharyngeal arches 1-3 skeleton - face bones, palate, smaller bones (ear ossicles, styloid process, hyoid) are from _________.
Neural crest
Pharyngeal arches 4-6 - laryngeal cartilages (thyroid, cricoid) are from?
Lateral plate mesoderm
Posterior part of the skull is from ____________.
Paraxial mesoderm
___________ forms part of the skeleton and all ANS ganglia.
Neural crest
Pharyngeal arches rows of thickened regions of the head and neck which are filled with mesenchyme (undifferentiated cells) migrating from _____________ and __________.
Mesoderm and neural crest
What are the narrow spaces between the pharyngeal arches inside and outside respectively?
Outside: Pharyngeal cleft, lined with ectoderm
Inside: Pharyngeal pouch, lined with endoderm
What does the first pair of pharyngeal arch do?
Surround a space to form stomodeum (primordial mouth) > maxillary x2 and mandibular x2 prominences.
Above the 1st arches, the mesenchyme forms an eminence above the stomodeum named?
Frontonasal prominence
> > total number of prominences = 5 (together with maxillary prominences + mandibular prominences)
Rupture of the _______________ between the primordial mouth and pharynx results in the mouth.
Oropharygeal membrane
Which of the followings are components of the pharyngeal arch? A. Cartilage bar B. Muscular tissue C. Artery D. Vein E. Cranial nerve (CN5,7,9,10) F. Mesenchyme
All except D
Pharyngeal arch 1 is the __________ arch that forms the skeleton of the mandible, maxilla, zygomatic. Will Meckel’s cartilage persist?
Mandibular;
no, except it forms the incus and malleus