Embryology/Histology Flashcards
What is the epithelium for the False vocal cords?
Pseudostratified columnar ciliated with goblet cells
What is the epithelium for the true vocal folds?
Stratified squamous non-keratinised
Which cartilage is the only cartilage to form a complete ring?
Cricoid cartilage
Where did the Larynx develop from?
Develops from laryngotracheal groove at caudal end of floor of primitive pharynx.
From which arches were the laryngeal cartilages developed from?
Fourth and Sixth
What type of epithelium lines the Nasopharynx?
Pseudostratified columnar ciliated with goblet cells
At what time does respiratory diverticulum (lung bud) starter develop?
At 4 weeks
What are the two respiratory epithelium field from which the respiratory system is developed?
Cephalad and Caudal
What is another name for pharyngeal tube?
Stomodeum
Fill in the blanks. “Cilliary activity in the cells of the respiratory fields will beat and propel secretions distally in the direction of the ______.
Buccopharyngeal membrane
What level of the stomodeum will the cephalic respiratory system occupy and what structures will it give rise to?
It will occupy the FLOOR of the stomodeum and will give rise to Respiratory diverticulum and its derivatives .
Ceph(F)Alice - Floor
What level of the stomodeum will the caudal respiratory system occupy and what structures will it give rise to?
It will occupy the PROXIMAL ROOF of the stomodeum and it will give rise to respiratory lining of the nasal cavity and its derivatives.
What structure does the central region of the pharyngeal tube develop into?
The oropharynx
What area of the respiratory system does the respiratory diverticulum develop into and what structures does it give rise to?
Develops into the lower respiratory tract airway - gives rise to Larynx, Trachea, Bronchi, bronchioles, terminal bronchioles
At what time and location does the pharyngeal apparatus develop ?
It develops during the 4-5th week, and devolves into the PROXIMAL foregut.
Which pharyngeal arches remain rudimentary and deep within the sternum?
5th and 6th Arch
At which pharyngeal arch is the Thyroid cartilage developed from?
4th arch
Which cartilage is developed from the 6th pharyngeal arch?
Cricoid
Fill in the blanks. “ The second pharyngeal arch gives rise to the ______ hyoid bone while the third arch gives rise to the ______ hyoid bone.
Second- Upper hyoid
Third- Lower hyoid
What external features arise from the first pharyngeal arch?
Maxillary and Mandibular swellings
In the interval separating of the 6 arches, what is located externally and internally?
Externally - Pharyngeal clefts
Internally - Pharyngeal pouches
“ Externally - clEft “
Fill in the blanks.” In the first interval between __ and ____ pharyngeal arches, the pharyngeal cleft and pharyngeal pouch come into proximity to form the ________.”
First and Second pharyngeal arches
Pharyngeal membrane
Where are the the bones and cartilagenous components of the pharyngeal arches are derived from?
Neural Crest Mesenchyme
True or False. The skeletal muscle and vascular component are derived from original mesenchyme, Somatic mesoderm.
FALSE!! They are derived from SPLANCHNIC mesoderm.
Which nerve is a derivative the 4th pharyngeal arch?
Vagal plexus and superior laryngeal nerve
The recurrent laryngeal nerve is a derivative which pharyngeal arch?
5 th arch
Fill in the blanks.” The first pharyngeal arch has derivatives of the _____ and ____ nerves .
Maxillary and mandibular
True or False? The trigeminal nerve is a derivative from the Sixth pharyngeal arch is supplied by the.
FALSE!! The Vagus nerve is a derivative of the SIXTH pharyngeal arch
Fill in the blank. The ______ pharyngeal arch has the Facial nerve as a derivative while the the______ nerve is a derivative of the third pharyngeal arch.
Second -Facial
Third- Glossopharyngeal nerve
What artery is associated with the third pharyngeal arch?
Common carotid artery
Proximal internal carotid artery
The Stapedial artery is associated with with pharyngeal arch?
Second pharyngeal arch
“ Second - Stapedial”
What arteries are associated with the sixth pharyngeal arch?
Pulmonary arteries ( proximal part) and Ductus arteriosus
“6PD - G6PD”
Fill in the blanks the ________ pharyngeal arch is associated with the arch or the aorta and _____.
Fourth - Arch of aorta and RIGHT Subclavian artery
True or False? The first pharyngeal arch is associated with part of the mandibular artery.
FALSE!!! Part of MAXILLARY artery
Fill in the bank, As a derivative of the first pharyngeal arch the mandible develops by intra membranous ossification around ________.”
Mechel’s cartillage
Which respiratory muscles are derived from the First Pharyngeal arch?
Muscles of mastication
Mylohyoid
Anterior belly of digastric
Tensor tympani
Tensor veli palatini
“MMATT came First “
Which bones are developed from the First pharyngeal arch?
Zygomatic
Greater wing of spenoid
Mandible
Maxilla
Squamus part of Temporal bone
“Ziggy Got MMS First”
True or False? The Lower part of of the body and lesser horn of hyoid bon is a second pharyngeal arch derivative.
FALSE!!!! The Upper part of the body and lesser horn of hyoid bone is a second arch derivative
” UPlesS- UPS”- the delivery thingi
Which muscles are derived from the second pharyngeal arch?
Posterior belly of digastric
Muscles of facial expression.
Stapedius
Stylohyoid muscle
” this is the SECOND time getting PMSS”
True or False? The lower part of the body and the greater horn of hyoid bone is a third pharyngeal arch derivative.
TRUE!!
” if you don’t love me now ,don’t love me later… when my later(lower) is much greater”
True or False? The salpingopharyngeous muscle is a derivative from the third pharyngeal arch?
FALSE!!! STYLOPHARYNGEOUS is from the THIRD arch!!
Fill in the blank. The ______ of the nucleus ambiguous is a third arch derivative while the ________ of the nucleus ambiguous is a fourth arch derivative.
Body-Third ( body of Christ - 3 in 1)
Head- Fourth ( Lazarus head forth)
The Palatoglossus, palatopharyngeus,
Pharyngeal constrictors,Levator veli palatine,
Salpingopharyngeus, Cricothyroid – external laryngeal muscles are derivatives from which pharyngeal arch?
Fourth
“PPPLS Come For(4) me”
Which muscles are derived from the sixth arch?
Intrinsic muscles of the Larynx
-Cricoarytenoideus ( posterior and lateral )
Cricopharyngeus
Arythenoideus ( Transverse and oblique Arythenoideus ( Transverse and oblique )
Thyroarytenoideus
Thyroepiglotticus
I had 6 CCAATTs and 5 kittens one time
At what time does the tongue start to appear?
4th week
Which pharyngeal arches does the Copula ( Posterior part of the tongue) & Epiglottis derive from?
2nd, 3rd & 4th arches
What part of the tongue is derived from the First pharyngeal arch?
Body ( Anterior 2/3)
Lateral lingual swellings
Medial lingual swellings
From which pharyngeal arch does the Hypobranchial emminece derive from?
2nd, 3rd, & 4th arches ( IT IS AKA COPULA)
From which pharyngeal arch does the Tuberculum impar derive from?
First pharyngeal arch - IT IS AKA Medial lingual swellings .
Fill in the blanks.” Within the cupola, the 3rd pharyngeal arch component overgrows the 2nd arch, and forms the ______”
Mucosa of the posterior 1/3 of the tongue.
True or False? The anterior 2/3 ( formed by lateral & medial lingual swelling) and posterior 1/3 (formed by copula ) of the tongue fuse – forming a V-shaped groove known as the Terminal Sulcus.
TRUE!!
What is the name of the “pit” that represents the origin of the thyroid gland?
Foramen cecum - pit in centre of the groove ( Terminal Sulcus)
What is the name of the structure that anchors the tongue in the mouth?
Lingual frenulum
What structure does the VENTRAL part of the THIRD pharyngeal pouch form?
Thymus
What structure does the DORSAL part of the THIRD pharyngeal pouch form?
Inferior parathyroid glands
True or False? The first pharyngeal push gives rise to the tubotympanic recess.
TRUE!!
What structures are included in the Tubotympanic recess?
Pharyngotympanic tube
Tympanic cavity and mastoid antrum
Inner layer of the ear drum
What structure does the second pharyngeal pouch give rise to?
Tonsillar fossa - including tonsillar crypts.
In the FOURTH pharyngeal pouch what structure does the ventral part give rise to?
Ultimopharyngeal body
Parafollicular cell
What is the function of Parafollicular cells?
migrate to the thyroid gland and produce calcitonin. They are of neural crest origin.
In the FOURTH pharyngeal pouch what structure does the dorsal part give rise to?
Superior parathyroid glands
Fill in the blanks. “The first pharyngeal cleft gives rise to _________ and _______.”
External auditory meatus and Outer layer of tympanic membrane
The Lateral cervical cyst ,External & Internal branchial fistula all arise from which pharyngeal cleft?
2nd 3rd and 4th clefts
The Lateral cervical cyst ,External & Internal branchial fistula are located along anterior edge of which muscle?
Sternocleidomastoid muscle
At what time does the face begin to develop?
24- 38th day
What are the three processes surrounding the stomadeum?
Frontonasal process
Maxillary process
Mandibular process
From which structure will give the future tympanic membrane?
Nasal Pits
Fill in the blanks.”Failure of the maxillary prominence and the lateral nasal prominence to fuse will result in ______”
Oblique facial cleft
What structure is the nose bridge formed from?
The frontal prominence
Fill in the blanks. The _______ and_______ is formed from the fused medial nasal prominence
Nasal Crest and Nose Tip
What structure is the Ala of the nose formed from?
Lateral nasal prominence.
“aLa - Lateral”
What structure of the upper lip will the globular process form?
Phyltrum and central area of the upper lip
What happens in the 7th week in regards to the development of the nasal cavity?
Oronasal membrane breakdown forming the
primitive choanae on either side of the midline
What happens in the 6th week in regards to the development of the nasal cavity?
*Nasal pit deepen and expand due to growth of the nasal prominence
*With further expansion, the nasal sacs approximate the oral cavity forming the oronasal membrane
Fill in the blanks. “Failure of palatal processes to fuse results in _____”
Cleft palate
True or False? Failure of medial nasal and maxillary prominences to merge results in medial cleft lip
FALSE!! It results in Lateral cleft lip
Fill in the blanks. “Failure of medial nasal prominences to merge results in ______”
Median cleft lip
An increase in what substance , from surrounding mesenchyme ,causes an up-regulation of a transcription factor TBX4?
Retinoic Acid
What is the function of TBX4?
TBX4 induces formation, growth and differentiation of the entire respiratory diverticulum.
At what time period does the Laryngo-tracheal groove appear then develops into a diverticulum?
4th week
Fill in the blank’ The respiratory primordium maintains its communication with the pharynx through the ______”
Laryngeal Orifice ( It’s the cavity)
From which pharyngeal arch will the laryngeal muscles develop from?
4th and 6th
What structure is developed from endothelial cells invading the laryngeal orifcie?
Vocal cords
At what time period, does the bronchial buds enlarge to form right and left main bronchi?
5th week
At the end of the 5th week, how many territory bronchi will be on the right side and on the left side>
Right side- 10 Tertiary bronchi
Left side- 8 Tertiary bronchi
Around what time period is the Pseudo-glandular stage?
Week 5-16
Which stage of Lung maturation is from week 16-26?
Canalicular stage
Around what time period is the Terminal sac (secular) stage?
Week 26 – Birth
Up to what age does the alveolar stage begin and end?
Week 36 - up to 8 years old
When do Type II pneumocytes develop?
After 6 months
What is the function of Type II pneumocytes?
They produce surfactant which DECREASES surface tension and prevent alveoli from collapsing
What is the function of Type I pneumocytes?
They allow for gas exchage
When does foetal breathing begin?
At week 16
From what structures do the diaphragm develop?
Septum transversum
Pleuro-peritoneal membrane
Dorsal mesentery of esophagus
Marginal ingrowth from body wal
What structure of the diaphragm will form the base of the pericardial sac?
The cephalic surface of the central tendon
What two structures fuse to form the diaphragm and what time does this occur?
Dorsal mesentry of the oesophagus and septum transversum ( In 7th week)
What type of cells are Type I pneumocytes?
Simple squamous cells
What type of cells are Type II pneumocytes?
Simple cuboidal cells
What germ layers is the respiratory system developed from?
Endoderm and Lateral Plate Splanchnic Mesoderm
What structures are developed from the endoderm?
Epithelial lining of larynx, trachea, and bronchi, as well as that of the lungs
What structures are developed from the splanchnic mesoderm?
Cartilaginous, muscular, and connective tissue components of the trachea and lungs.
What are the the associated effects of a tracheoesphageal fistula?
Vetebral anomalies
Anal atresia
Cardiac defects
Tracheaoesophageal fistula
Renal anomalies
Limb defects
From which germ layer is Visceral Pleura developed from?
Mesoderm
True or False? Mature Alveoli are not present before birth.
TRUE!!
Explain the concept of contractions felt right before birth.
Once there is an increase in surfactant , after 34 weeks gestation- the surfactant enters the amniotic fluid and act on the macrophages in the amniotic cavity. These macrophages then migrate to the chorion in uterus to stimulate the release of IL-1B. The up-regulation IL-1B then causes the release of prostaglandins that causes CONTRACTIONS.
From what structure does type II pneumocystis secrete surfactant?
From lamellar bodies
What is olfactory epithelium?
Pseudostratified tall columnar epithelium without goblet cells and without motile ciliae (lack of dynein).
What are the type of cells present in Olfactory epithelium?
supportive
basal
olfactory (sensory)
Where are Bowman’s glands located?
Lamina propria of mucosa
What type of epithelium lines the base of the epiglottis?
Pseudostratified ciliated columnar epithelium
What type of epithelium lines the lingual of the epiglottis?
Stratified squamous epithelium
What type of cells are brush cells?
Columnar cells
True or False? In large bronchioles the epithelium is pseudo stratified epithelium with NO goblet cells.
TRUE!!
What type of epithelium is found in terminal bronchioles?
Cuboid Epithelium
What type of cells are found in the terminal bronchioles?
Clara/club cells
What are dust cells?
Alveolar macrophages
Where dust cells found?
Alveoli and in interalveolar septum
What is the main connexin found in ventricular myocardium?
Cx43
