Final: Chapter Questions Flashcards
Neural crest-derived cells constitute a significant component of which tissue of the eye?
Cornea
The otic placode arises through an inductive message given off by the?
Rhombencephalon
What molecule plays a role in guidance of advancing retinal axons through the optic nerve?
Pax-2
Surface ectoderm is induced to become corneal epithelium by an inductive event originating in the?
Lens vesicle
What extracellular matrix molecule is often associated with migrations of mesenchymal cells, and where does such an event occur in the developing eye?
Hyaluronic acid.
Occurs int he primary corneal stroma
Which of the following is caused by failure of the choroid fissure to close during the 6th week of pregnancy?
Colobomo
A 15-year-old boy with mild acne developed a tender boil along the anterior border of the SCM muscle. What embryological condition would e included in a differential diagnosis?
Branchial cyst
The facial nerve supplies muscles derived from which pharyngeal arch?
Second
Cleft lip results from lack of fusion of the…?
Nasomedial & maxillary processes
In cases of holoprosencephaly, defects of facial structures are typically secondary to defects of the…?
Forebrain
Meckel’s cartilage is a prominent structure in the early formation of the…?
Lower jaw
An early induction in tooth development consists of the ectoderm of the dental epithelium acting on the underlying neural crest mesenchyme. Which of the following molecules is an important mediator of the inductive stimulus?
BMP-4
Why does a person sometimes get a runny nose while crying?
Secretions of lacrimal glands enter nasolacrimal ducts carrying lacrimal fluid into the nasal cavity
Which of the following does not connect directly with the primary nephric (mesonephric) duct?
Metanephros
Which association is correct?
GDNF & metanephrogenic blastema
Which defect is strongly associated with oligohydramnios?
Renal agenesis
Which anomaly is most closely associated with exstrophy of the bladder?
Epispadias
The uterus arises from the…?
Paramesonephric ducts
The floor of the penile urethra in them ale is homologous to what structure in the female?
Labia minora
The metanephrogenic blastema is induced by the…?
Ureteric bud
Drops of yellowish fluid were observed around the umbilicus of a young infant. what is a likely diagnosis, and what is the embryological basis?
Urachal fistula
A woman who gained relatively little weight during pregnancy gives birth to an infant with large, low-set ears, a flattened nose, and wide interpupillary space. Within hours after birth, the infant is in distress and dies after 2 days. What is the diagnosis?
Bilateral renal agenesis
The internal carotid artery arises from aortic arch number…?
3
What is the embryological basis for a duplication of the inferior vena cava caudal to the kidneys?
Persistence of caudal segment of left supracardinal vein
Nucleated erythrocytes found circulating in the embryo are produced in the…?
Yolk sac
In a 7-month fetus, blood draining the left temporalis muscle enters the heart via the…?
Superior vena cava
Adherons are inductive particles released by what structure int eh endocardial cushion area?
Myocardium
Neural crest contributes to the structure of which of the following?
All of the above
Truncus arteriosus, Ascending aorta, Pulmonary trunk
For which of these cardiovascular malformations is a patent ductus arteriosus necessary for survival of the individual?
None of the above
Five days after birth, an infant becomes cyanotic during a prolonged crying spell. The cyanosis is most likely caused by venous blood entering the systemic circulation through the…?
Interatrial septum
The internal carotid artery arises from aortic arch number…?
3
