What is the stomadeum and what are its borders?

- a depression between the brain and the pericardium in an embryo, and is the precursor of the mouth and the anterior lobe of the pituitary gland.
- Boundaries

Cranial - Frontonasal Prominence

Caudal - Mandibular Processes

Lateral - Maxillary Processes

Deep- Oropharyngeal membrane

What are the three components of the Pharyngeal apparatus?

- arches

- intervening endodermal pouches

- ectodermal clefts separated by a membrane

What can be found in a pharyngeal arch?

aortic arch, cartilage, muscle and nerve

What pharyngeal membrane becomes a membrane that consists of ectoderm, mesoderm, and endoderm but is almost transluscent?

1st pharyngeal membrane (becomes tympanic membrane)

What skeletal, muscular, vascular, and neurological features are derived from the 1st pharyngeal arch?

Maxillary process (Maxilla, Zygomatic, Temporal bone)

Mandibular Process (Mandible, Incus and Malleus)

Muscles of Mastication

Ant Digastric, Mylohyoid, Tensor Tympani, Tensor Palatini

Trigeminal - CN V

Motor- V3

Sensory - V1, V2, V3

Maxillary arteries

What skeletal, muscular, vascular, and neurological features are derived from the 2nd pharyngeal arch?

Hyoid

Ventral - Cranial 1/2 of hyoid

Dorsal- Stapes, Styloid process of temporal bone and Stylohyoid ligament

Muscles of Facial Expression (CN VII)

Stapedius, Stylohyoid, Post Digastric, Auricular

Facial (VII; motor)

Hyoid and Stapedial Arteries (regress in utero)

What skeletal, muscular, vascular, and neurological features are derived from the 3rd pharyngeal arch?

Lower hyoid

Stylopharyngeus

Glossopharyngeal (CN IX; motor)

Internal and Common Carotid Arteries

What skeletal, muscular, vascular, and neurological features are derived from the 4th pharyngeal arch?

Laryngeal cartilages

Cricothyroid, Levator Palatini, Pharyngeal Constrictors

Superior Laryngeal Branch of Vagas (CN X; motor)

R - Subclavian artery

L - Arch of the Aorta

What skeletal, muscular, vascular, and neurological features are derived from the 6th pharyngeal arch?

Laryngeal cartilages

Intrinsic laryngeal muscles

Recurrent Laryngeal Branch of Vagas (CN X; motor)

Pulmonary Arteries (persistent ductus arteriosus?)

What parts of the pharyngeal apparatus can grow to form a cervical sinus that has the potential to persist as a lateral painless cystic neck mass?

2nd and 4th arches over the 2nd, 3rd, and 4th clefts/grooves

What structure does the 1st cleft of the pharyngeal apparatus persist as?

External Auditory Canal

What structures are formed from the 1st endodermal pharyngeal pouch?

Middle ear cavity

Eustachian tube

What structure are formed from the 2nd endodermal pharyngeal pouch?

Palatine Tonsil

What structures are formed from the 3rd endodermal pharyngeal pouch?

Ventral - Thymus

Dorsal - Inferior parathyroid

What structures are formed from the 4th/5th endodermal pharyngeal pouch?

Superior parathyroid

Ultimobranchial body (calcitonin producing "c-cells")

Which pharyngeal arch makes up the anterior 2/3 of the tongue and what fuses to create the tongue as we know it in adulthood?

Arch I from the Lateral Lingual Swellings and Tubercum impar

Which arches make up the posterior 1/3 of the tongue and what respective swellings fuse to form the tongue as we know it in adulthood?

2nd-4th arches

3rd - Inferior medial swelling (Copula)

4th- Hypobranchial Eminence (epiglotal swelling)

What is the anterior 2/3 of the tongue innervation?

Sensory - CN V

Taste - CN VII

Motor - CN XII

What is the posterior 1/3 of the tongue's innervation?

Sensory - CN IX, CN X

Taste - CN IX, CN X

Motor - CN XII

What is the origin of the thyroid's descent in the neck?

Foramen cecum

What structure separates the anterior 2/3's of the tongue from the posterior 1/3?

Terminal sulcus