Formation of tongue

Question 1

tongue formation occurs when

Answer 1

between 4th and 12th week of pregnancy

Question 2

the tongue is divided into two parts

Answer 2

• anterior 2/3 body of tongue
• posterior 1/3 base

Question 3

explain the formation of body of tongue

Answer 3

its from the 1st branchial arch it begins with 3 lateral swellings which is

-2 lateral lingual swellings: main contributors to the body of tongue and arise from mesenchyme in 1st arch

-Tuberculum impair: midline swelling appears initially between the 2 lateral lingual swellings and becomes insignificant as development progresses

so the lateral lingual swellings grow larger and eventually fuse at midline to give us the ant 2/3

Question 4

the 3 swellings of body of tongue originate from where

Answer 4

the mesenchyme of 1st brachial arch

Question 5

explain the formation of the base of tongue

Answer 5

formed from copular or hyobranchial eminence) which is a swelling that originates from 3rd with small contribution from 4th the copula then overgrows 2nd brachial arch and extends towards body
eventually copula+ ant part of tongue merge to create tongue

Question 6

tongue origin ps list the nerve

Answer 6

1- ANTERIOR 2/3: 1st brachial arch ( trigeminal nerve which is the 5th cranial nerve)

2- POSTERIOR 1/3: 3rd and 4th brachial arch ( glossopharyngeal nerve 9th and vagus 10th)

Question 7

taste sensation is split by development

Answer 7

Ant 2/3: gets taste sensation from facial nerve 7th
Post 1/3: conveys both taste and general sensation through glossopharyngeal 9th

Question 8

what does the tip of tongue forms and what is it called

Answer 8

forms U shaped sulcus called lingual frenulum which separates the tongue from floor of mouth

Question 9

what happens if the lingual frenulum is short and position of insertion anterior

Answer 9

speech disorders
postnatal feeding

Question 10

what covers the body and the base of tongue

Answer 10

body : ectoderm
base : endoderm

Question 11

what is the name of the sulcus where the body and base of tongue meet

Answer 11

terminal sulcus which is a v shaped sulcus

Question 12

what is the name of the foramen that helps in the formation of thyroid gland and where is it located

Answer 12

foramen cecum located at the tip of the v

Question 13

name the rounded masses of lymphatic tissue that cover the posterior region of tongue

Answer 13

lingual tonsils

Question 14

location of lingual tonsils

Answer 14

dorsal surface at the base of tongue

Question 15

describe lingual tonsils lymphatic tissue

Answer 15

its dense and nodular covered with stratified squamous nonkeratinized epithelium

Question 16

the muscles of tongue originate from where

Answer 16

from the migration of the occipital somite’s

Question 17

which nerve innervate the muscles

Answer 17

12th cranial nerve ( hypoglossal nerve)