CFB: The Tongue

Question 1

What are intrinsic muscles?

Answer 1

Muscles originate and attach to other structures within the tongue

Question 2

How many pairs of intrinsic muscles are there?

Answer 2

4

Question 3

What are the intrinsic muscles named by?

Answer 3

Direction in which they travel

Question 4

Name the 4 intrinsic muscles

Answer 4

Superior longitudinal
Inferior longitudinal
Transverse
Vertical

Question 5

What nerve supplies the motor function of the intrinsic muscles?

Answer 5

Hypoglossal

Question 6

What are the extrinsic muscles?

Answer 6

Originate from structures outside the tongue and insert onto it

Question 7

Names of extrinsic muscles

Answer 7

Genioglossus
Hyoglossus
Styloglossus
Palatoglossus

Question 8

What nerve innervates the extrinsic muscles

Answer 8

Hypoglossal nerve EXCEPT palatoglossus which is innervates by vagus

Question 9

Attachments of Genioglossus

Answer 9

Arises from the Mandibular symphysis.
Inserts onto the body of the hyoid bone and the entire length of the tongue

Question 10

Function of Genioglossus

Answer 10

Protrusion and depression of tongue

Question 11

Innervation of Genioglossus

Answer 11

Hypoglossal

Question 12

Attachments of hyoglossus

Answer 12

Arises from the hyoid bone
Inserts onto the lateral aspect of the tongue

Question 13

Function of hyoglossus

Answer 13

Depression and retraction of the tongue

Question 14

Innervation of hyoglossus

Answer 14

Hypoglossal

Question 15

Attachments of styloglossus

Answer 15

Originates from styloid process of temporal
Inserts onto the lateral aspect of the tongue

Question 16

Function of styloglossus

Answer 16

Retraction and elevation of tongue

Question 17

Innervation of styloglossus

Answer 17

Hypoglossal

Question 18

Attachments of palatoglossus

Answer 18

Arises from the palatine aponeurosis
Inserts broadly along tongue

Question 19

Function of palatoglossus

Answer 19

Elevation of posterior tongue

Question 20

Innervation of palatoglossus

Answer 20

Vagus nerve

Question 21

What nerve provides general sensation to anterior 2/3 of tongue?

Answer 21

Trigeminal nerve- lingual nerve branch of mandibular nerve

Question 22

What nerve provides taste in the anterior 2/3 of tongue?

Answer 22

Facial nerve- in petrous part of temporal bone, facial nerve gives off three branches- chorda tympani which travels through middle ear and continues to tongue

Question 23

What nerve supplies both sensory and taste to posterior 1/3 of tongue?

Answer 23

Glossopharyngeal nerve

Question 24

Vasculature of tongue

Answer 24

Lingual artery- branch of external carotid (most of supply)
Tonsillar artery- branch of facial artery (provides some collateral circulation)
Drainage by lingual nerve

Question 25

Lymphatic drainage of anterior 2/3 of tongue

Answer 25

Initially into the submental and submandibular node which empty onto deep cervical lymph nodes

Question 26

Lymphatic drainage of posterior 1/3 of the tongue

Answer 26

Directly into the deep cervical lymph nodes

Question 27

When does the tongue start to develop?

Answer 27

4th week of gestation

Question 28

What is the tongue derived from?

Answer 28

Pharyngeal arches 1-4 (forms mucosa of tongue) Occipital somites (forms musculature of tongue p)

Question 29

Lateral lingual swellings of tongue (during development)

Answer 29

Derived from 1st pharyngeal arch Contribute to mucosa of anterior 2/3 of tongue

Question 30

How many lingual swelling are there during development?

Answer 30

2

Question 31

Medial swellings of tongue (during development)

Answer 31

Tuberculum impar: derived from 1st pharyngeal arch. Contributes to anterior 2/3 mucosa Cupola: derived from 2nd,3rd,4th pharyngeal arch. Forms posterior 1/3 mucosa Epiglottal swelling: derived from 4th pharyngeal arch. Forms the epiglottis

Question 32

How is the anterior 2/3 mucosa formed

Answer 32

During 5th week of development Lateral lingual swellings overgrown the tuberculum impar and merge together Line of fusion is marked by the median sulcus of tongue

Question 33

What happens within the cupola to form the mucosa of posterior 1/3

Answer 33

During 5th week of development 3rd pharyngeal arch component overgrows the 2nd arch

Question 34

What happens during week 8 of gestation in relation to tongue development?

Answer 34

Anterior 2/3 and posterior 1/3 fuse Forms a v shapes groove called the terminal sulcus- at the centre of this groove is the foramen cecum which represents the place of origin of the thyroid gland

Question 35

Development of lingual frenulum

Answer 35

Tongue is initially tethered to the floor of the oral cavity Process of carefully programmed cell death known as sculpting apoptosis releases the tongue

Question 36

Occipital somites

Answer 36

Segments of mesoderm in the region of the upper neck Intrinsic and extrinsic muscles are derived from occipital somites The somites migrate from the neck anteriorly to give rise to tongue muscles