Lecture 4 Flashcards
Which of the following structures is located ventral to the rhombencephalon in the 4th week of development?
A) Notochord
B) Primitive brain vesicles
C) Primordial pharynx
D) Neural crest cells
C) Primordial Pharynx
At the end of the 4th week, the center of the face is formed by the stomodeum, which is surrounded by which structures?
A) Second pair of pharyngeal arches
B) First pair of pharyngeal arches
C) Maxillary prominences
D) Mandibular prominences
B) First pair of Pharyngeal arches
During the 4th week, which membrane reabsorbs to establish continuity between the primitive mouth and the foregut?
A) Oropharyngeal membrane
B) Nasolacrimal membrane
C) Neural membrane
D) Pharyngeal membrane
A) Oropharyngeal membrane
Which prominence forms cranial to the stomodeum during the 4th week of development?
A) Mandibular prominence
B) Maxillary prominence
C) Frontonasal prominence
D) Lateral nasal prominence
C) Frontonasal Prominence
The nasal placodes divide the frontonasal prominence into which of the following processes?
A) Maxillary and mandibular processes
B) Lateral and medial nasal processes
C) Frontonasal and mandibular processes
D) Nasal and optic processes
B) Lateral and medial nasal processes
Which structure forms the middle portion of the upper lip, including the philtrum, in the 5th week?
A) Maxillary prominences
B) Medial nasal processes
C) Mandibular prominences
D) Lateral nasal processes
B) Medial Nasal Processes
The nasolacrimal groove, formed between the lateral nasal process and the maxillary prominence, will eventually become which structure?
A) Nasolacrimal duct
B) Incisive canal
C) Lacrimal bone
D) Nasal pits
A) Nasolacrimal duct
The fusion of the palatine processes with the primary palate leaves which structure in the median area?
A) Nasal pits
B) Incisive foramen
C) Lacrimal bone
D) Mandibular prominence
B) Incisive foramen
How many pharyngeal arches develop during the 4th week on the sides of the embryo’s head?
A) Four
B) Five
C) Six
D) Seven
C) six
By which week does the cervical sinus along with the 2nd, 3rd, and 4th pharyngeal grooves disappear due to the growth of the 3rd and 4th pharyngeal arches?
A) Week 4
B) Week 5
C) Week 6
D) Week 7
D) Week 7
Pharyngeal arches roles
• Development of the sides of the head and neck
• Development of the Viscerocranium and to a small portion of the neurocranium
• Genesis of blood vessels of the head and neck
Cervical sinus formation
Formed in week 5 when the 2nd arch grows and overtakes the 3rd and 4th arches
What separates Pharyngeal arches
ectodermal pharyngeal grooves
