Lecture 44 Branchial Arches Flashcards
what are the four components of the branchial “apparatus”?
branchial (pharyngeal) arches; pharyngeal pouches, branchial grooves (clefts), and branchial membranes
what are the four components of each branchial (pharyngeal) arch?
nerve, muscle, skeletal/cartilage, and aortic arch
Nerves associated with the branchial arches are referred to as what kind of nerves?
branchiomeric nerves
Name the five “branchiomeric” nerves.
CN V, CN VII, CN IX, CN X, and CN XI
The muscle group related to branchial arch 1 is _____ mm and the muscle group related to branchial arch 2 is ______ mm.
masticatory, facial
Which pharyngeal pouch is related to the pharyngotympanic tube?
First
The thymus and parathyroids are related to which pharyngeal pouch(es)?
Third and Fourth
The first branchial membrane is related to what derivative in adults?
Tympanic membrane
How many branchial arches are said to exist in humans?
Six, though the existence of the fifth remains unclear and is usually considered together with the sixth or the fourth
On the lateral aspect of the head region of the embryo, how many branchial arches can be visualized?
Four
The second branchial arch is sometimes referred to as the ________ arch.
Hyoid
By the _____ week, all branchial swellings (4) are visible.
4th week (~28 +/- 1 day)
Muscles derived from the branchial (pharyngeal) arches come from two species. Describe them.
Those that form in the mesenchyme of the branchial arch, receiving cues from neural crest cells
Muscles that migrate into the head and neck region that come from myotomes (myotomal portion of somites)
What structures migrate into the branchial (pharyngeal) aches to assist in forming their derivatives?
neural crest cells
What skeletal element is related to the first branchial (pharyngeal) arch? What about the second branchial (pharyngeal) arch?
Meckel’s cartilage
Reichert’s cartilage
What nerve is related to the sixth aortic arch, the derivative being the ligamentum arteriosum?
L recurrent laryngeal nerve
What is the first endocrine gland to appear during development at approximately 24 days?
Thyroid gland
Developmentally, the thyroid chisels through the _____ and ends up at the _____ aspect of the throat, sitting in front of the _____.
Tongue
Anterior
Larynx
Name three variations or malformations that can result from incorrect descent of the thyroid.
Pyramidal lobes/persistent thyroglossal duct
Thyroglossal duct cysts and sinuses
Ectopic thyroid gland
What temporary structure appears where the branchial groove and pharyngeal pouch approach one another?
Branchial membrane
What syndrome results due to damage of Meckel’s cartilage, resulting in micrognathia (shortened mandible)?
Pierre Robin Sequence
The 2nd-4th branchial grooves (pharyngeal clefts) temporarily exist as ______, which usually disappears.
Common cervical sinus
The first branchial arch is also known as the ______ arch.
Mandibular
Which branchial arch forms the upper portion of the malleus and incus?
1st branchial arch
Which branchial arch forms the lower portion of the malleus, incus, and stapes, styloid process of the skull, and portions of the hyoid?
3rd branchial arch
Which branchial arch forms the thyroid cartilage of the larynx?
4th branchial arch
Which arch(es) form the cricoid, arytenoid, corniculate, and cuneiform cartilages of the larynx?
5th and 6th branchial arches
Trigeminal (CN V) is to the ______ arch.
First
Glossopharyngeal (CN IX) is to the _______ arch.
Third
Vagus (CN X), specifically the superior laryngeal nerve, is to the ______ arch.
Fourth
Cranial root of the Spinal Accessory (CN XI) fibers carried in the recurrent laryngeal nerve (of the Vagus) is to the _______ arch(es).
Fifth and Sixth
The first branchial arch is related to what artery derivatives?
1st pair of aortic arches and maxillary artery
The second branchial arch is related to what artery derivatives?
2nd pair of aortic arches and stapedial artery
The third branchial arch is related to what artery derivatives?
3rd pair of aortic arches, proximal parts form common carotid, distal parts form portions of internal carotid
The fourth branchial arch is related to what artery derivatives?
4th pair of aortic arches, L arch forms part of the aortic arch, R arch forms part of the R subclavian
The fifth-sixth branchial arches are related to what artery derivatives?
6th pair of aortic arches, proximal part of the L arch forms the proximal pulmonary arteries, distal part of the L arch forms the ductus arteriosus
What branchial arch is associated with all muscles of mastication, the anterior belly of digastric, mylhoid, and tensors?
First branchial arch
What single muscle is associated with the 3rd branchial arch?
Stylopharyngeus
What branchial arch is associated with the cricothyroid muscle?
Fourth branchial arch
Which branchial arch is associated with all intrinsic muscles of the larynx except the cricothyroid?
Fifth-sixth branchial arches
The Facial Nerve (CN VII) is to the _______ arch.
Second
