Development of tongue and thyroid gland Flashcards
Early Events in Tongue Development
____, opens into a chamber that comprises the first portion of the gut tube, the pharynx.
Primitive mouth, or stomodeum
Early Events in Tongue Development
Posterior to the hypopharyngeal eminence is ____ and ____
the opening of the laryngotracheal groove, and the esophagus.
Early Events in Tongue Development
Primitive mouth, or stomodeum, opens into a chamber that comprises____
the first portion of the gut tube, the pharynx.
Early Events in Tongue Development
Primitive mouth, or stomodeum, opens into a chamber that comprises the first portion of the gut tube, the pharynx.
→ The endoderm that lines this space covers ____
each pharyngeal arch.
Early Events in Tongue Development
Muscles derived from (1)_____ migrate into floor of the pharynx and drag axons of the hypoglossal nerve with them as they migrate.
occipital somites
Early Events in Tongue Development
Muscles derived from occipital somites migrate into floor of the pharynx and drag axons of ____ with them as they migrate.
the hypoglossal nerve
Early Events in Tongue Development
Muscles derived from occipital somites migrate into floor of the pharynx and drag axons of the hypoglossal nerve with them as they migrate.
→ These muscles create ____ and ____ of under the first pharyngeal arch.
the lateral lingual swellings and median lingual swelling
Early Events in Tongue Development
Muscles derived from occipital somites migrate into floor of the pharynx and drag axons of the hypoglossal nerve with them as they migrate.
→ These muscles create the lateral lingual swellings and median lingual swelling of under ____
the first pharyngeal arch.
Early Events in Tongue Development
What is the The copula?
a swelling of the second pharyngeal arch.
Early Events in Tongue Development
They create _____ under the third and fourth pharyngeal arches.
the hypopharyngeal eminence
Growth Up the Tongue
In the floor of the pharynx, ___ and _____ enlarge, begin to protrude anteriorly.
the lateral and median lingual swellings
Growth Up the Tongue
The third arch grows over ____, obliterating the copula.
the second arch
Growth Up the Tongue
The third arch grows over the second arch, obliterating __
the copula.
Growth Up the Tongue
In the floor of the pharynx, the lateral and median lingual swellings enlarge, begin to protrude anteriorly.
The third arch grows over the second arch, obliterating the copula.
This drags ____ toward the front of the oral opening.
the hypopharyngeal eminence
Growth Up the Tongue
In the floor of the pharynx, the lateral and median lingual swellings enlarge, begin to protrude anteriorly.
The third arch grows over the second arch, obliterating the copula.
This drags the hypopharyngeal eminence toward the front of ____
the oral opening.
Mature Appearance of the Tongue
The anterior 2/3 of the tongue
- is derived form ____
- is innervated by ____
- the first arch
- the mandibular division of the trigeminal nerve.
(Recall that muscles of the tongue are innervated by the hypoglossal nerve.)
Mature Appearance of the Tongue
Taste buds on the anterior 2/3rd of the tongue are separately innervated by ____
a branch of the facial nerve (chorda tympani)
(Recall that muscles of the tongue are innervated by the hypoglossal nerve.)
Mature Appearance of the Tongue
The posterior 1/3rd of the tongue
- is derived form ____
- is innervated by ____
- the third arch
- the glossopharyngeal nerve.
(Recall that muscles of the tongue are innervated by the hypoglossal nerve.)
Early Events in Tongue Development
→ Identify
Early Events in Tongue Development
→ Identify the arches with their corresponding nerves
Growth Up the Tongue
→ IDENTIFY
Mature Appearance of the Tongue
→ IDENTIFY
Identify 2
- Tuberculum impar
The lingual divisions & nerves
Pharyngeal arch: 1st
Tongue Primordia: ??
Cranial nerve: ??
Derivatives: ???
-
Tongue Primordia:
- Tuberculum impar
- lateral lingual swellings
- Cranial nerve: CN V/3
-
Derivatives:
- Connective tissue of tongue carrying CN 5/3 (lingual nerve, general sensation)
- Mucosa of anterior 2/3 of tongue lies above this part (ECTODERM!)
The lingual divisions & nerves
Pharyngeal arch: 2nd
Tongue Primordia: ??
Cranial nerve: ??
Derivatives: ???
- Tongue Primordia: NO!
- Cranial nerve: CN 7 (chorda tympani)
-
Derivatives:
- Connective tissue of tongue carrying CN 7 (chorda tympani)
- taste - anterior 2/3 of tongue
The lingual divisions & nerves
Pharyngeal arch: 3RD & 4TH
Tongue Primordia: ??
Cranial nerve:???
Derivatives: ???
- Tongue Primordia: Copula and hypopharyngeal (hypobranchial) eminence
- Cranial nerve: CN 9 and CN 10
-
Derivatives:
-
Connective tissue of the tongue
- General sensation and taste in the posterior 1/3 of tongue (CN9)
- General sensation and taste at the epiglottis (CN10)
- Mucosa of posterior 1/3 of tongue lies above this part (ENDODERM!)
-
Connective tissue of the tongue
The lingual divisions & nerves
Pharyngeal arch: 3RD & 4TH
Tongue Primordia: Copula and hypopharyngeal (hypobranchial) eminence
Cranial nerve: CN 9 and CN 10
Derivatives: ???
Derivatives:
-
Connective tissue of the tongue
- General sensation and taste in the posterior 1/3 of tongue (CN9)
- General sensation and taste at the epiglottis (CN10)
- Mucosa of posterior 1/3 of tongue lies above this part (ENDODERM!)
The lingual divisions & nerves
Tongue Primordia: Occipital somites
Cranial nerve: ??
Derivatives: ???
Cranial nerve: CN XII
Derivatives:
- all intrinsic tongue muscles;
- all extrinsic tongue muscles (except for palatoglossus)
Tongue and Thyroid Gland
→ Between the first and second arches is ____
a small invagination of endoderm, the foramen cecum.
Tongue and Thyroid Gland
→ Between the first and second arches is a small invagination of ___, the foramen cecum.
endoderm
Tongue and Thyroid Gland
The thyroid diverticulum is located at ____ and remains attached to it by the thyroglossal duct late into the 5th week of development.
the terminal end of the foramen cecum
Tongue and Thyroid Gland
____ is located at the terminal end of the foramen cecum and remains attached to it by the thyroglossal duct late into the 5th week of development.
The thyroid diverticulum
Tongue and Thyroid Gland
The thyroid diverticulum is located at the terminal end of the foramen cecum and remains attached to it by the ____late into the 5th week of development.
thyroglossal duct
Tongue and Thyroid Gland
The thyroid diverticulum is located at the terminal end of the foramen cecum and remains attached to it by the thyroglossal duct late into ____ (WEEK?)
the 5th week of development.
Decent of the Thyroid Gland
Descends as body elongates
Passes _____, comes to rest on the anterior surface of the trachea
the hyoid bone, laryngeal cartilages
Decent of the Thyroid Gland
Descends as body elongates
Passes the hyoid bone, laryngeal cartilages, comes to rest on ____
the anterior surface of the trachea
Decent of the Thyroid Gland
Descends as body elongates
Passes the hyoid bone, laryngeal cartilages, comes to rest on the anterior surface of the trachea
→ The thyroid bifurcates to produce ___ and ___ as it descends.
right and left lobes
Decent of the Thyroid Gland
Descends as body elongates
Passes the hyoid bone, laryngeal cartilages, comes to rest on the anterior surface of the trachea
→ The thyroid bifurcates to produce right and left lobes as it descends.
→ The thyroglossal duct rescinds and the ___ remains as a small pit on the surface of the tongue.
foramen cecum
Tongue and Thyroid Gland
→ Identify
Tongue and Thyroid Gland
→ identify
Foramen cecum
Tongue and Thyroid Gland
→ identify
Decent of the Thyroid Gland
