Anatomy One Liners (Embro Head And Neck, Miscellaneous, Changes At Birth)

Front 1

Branchial cleft derivatives

First cleft

Second - fourth cleft

Back 1

four pairs; ectoderm that forms only epithelium

1st cleft: gives rise to the external auditory meatus

2nd cleft: typically regress; may form a cervical sinus

Front 2

Pharyngeal Arches – There are five pharyngeal arches; mesoderm forms skeletal muscle; neural crest grows into each arch and forms all connective tissue (cartilage, bone and blood vessels)

Back 2

There are five pharyngeal arches; mesoderm forms skeletal muscle; neural crest grows into each arch and forms all connective tissue (cartilage, bone and blood vessels)

Front 3

1st pharyngal arches

Back 3

Muscles: muscles of mastication, anterior belly of digastric, mylohyoid, tensor tympani and tensor veli palatini

Artery: maxillary

Cartilage: malleus and incus

Front 4

2nd pharyngal arches

Back 4

Muscle: facial muscles, stapedius, posterior belly of digastric and stylohyoid

Artery: hyoid and stapedial

Cartilage: stapes, styloid process, lesser horn and superior portion of body of hyoid

Front 5

3rd pharyngal arches

Back 5

Muscle: Stylopharyngeus

Artery: common and internal carotid

Cartilage: greater horn and inferior portion of body of hyoid

Front 6

4th pharyngal arches

Back 6

Muscle: muscles of palate, pharynx and cricothyroid

Artery: left: portion of arch; right: part one of subclavian

Cartilage: laryngeal cartilage

Front 7

5th pharyngeal arches

Back 7

Muscle: muscles of larynx, inferior constrictor, cricopharyngeus and superior portion of esophagus

Artery: Pulmonary trunk (left - ductus arteriosus)

Cartilage: laryngeal cartilage

Front 8

Pharyngeal Pouches – four pairs; endoderm that forms only epithelium

What are the 1st - 4th pouches?

Back 8

The first pouch gives rise to the auditory tube, mastoid antrum and tympanic cavity.

The second pouch forms the palatine tonsil.

The third pouch gives rise to the thymus and inferior parathyroid gland.

The fourth pouch gives rise to the superior parathyroid

Front 9

Torticollis

Back 9

This is a condition characterized by a shortening of the sternocleidomastoid muscle and results in an elevation of the chin to the opposite side; can be caused by damage to the muscle, spinal accessory nerve or can be congenital.

Front 10

Cysts of the Neck

Lateral cervical cysts (branchial fistula)

Midline cysts

Back 10

Arises from the second through fourth pharyngeal clefts

Most often arise from a remnant of the thyroglossal duct (thyroglossal duct cysts)

Front 11

Cleft Lip

Back 11

Cleft Lip – Results from failure of the maxillary prominence to join the medial nasal prominences to form the intermaxillary segment (primary palate derives from intermaxillary segment)

Front 12

Cleft Palate

Anterior cleft

Posterior cleft

Complete cleft

Back 12

Anterior to incisive foramen; lateral palatine process fails to fuse with primary palate

Occurs through the secondary palate where lateral palatine process does not fuse or meet nasal septum


Involves both the primary and secondary palate

Front 13

Situs inversus

Diaphragm

Congenital diaphragmatic hernia

Stem villi

Intervillous space

Back 13

Reversal of organs; can involve all organs or just single organs (heart – dextrocardia)

Develops from the septum transversum, pleuroperitoneal membranes, paraxial mesoderm and dorsal mesentery of the esophagus

Results from a failure of the pleuroperitoneal fold to close the pericardioperitoneal canal; most common on the left side

Form trophoblast and somatic layer of extraembryonic mesoderm

Contains maternal blood

Front 14

Changes at birth:

umbilical arteries

umbilical vein

urachus

foramen ovale

ductus arteriosus

ductus venosus

Back 14

paired medial umbilical ligaments

round ligament of liver

median umbilical ligament

fossa ovalis

ligamentum arteriosum

ligamentum venosum