Congenital Arrhinia and Pharyngeal Arches Quiz

The process of forming the parts of the respiratory system, beginning in week 4 of development.

An indentation in the floor of the pharynx that gives rise to parts of the respiratory system.

A pouch-like outgrowth from the laryngotracheal groove.

The lining of the lung passages (pulmonary epithelium, glands, larynx, trachea, and bronchi) develop from the endoderm.

The surrounding tissues of the lungs (connective tissue, cartilage, and smooth muscle) develop from the splanchnic mesoderm.

Thickened areas of ectoderm that develop into the nasal pits.

Indentations in the embryo that develop into the nasal cavities.

Membrane separating the nasal sacs from the oral cavity.

Entrance to the nasal cavity.

Initial openings between the nasal cavity and pharynx.

Specialized epithelial cells that are sensitive to smells.

Specialized cells in the nose that detect odors.

Five embryonic structures that give rise to parts of the face.

Embryonic structure giving rise to parts of the forehead, nose and bridge.

Transcription factor that induces lung growth and differentiation.

Absence of external and internal nasal structures.

Complete duplication of the nose, forming two noses.

Rudimentary nasal structure or appendage off-centre from face's midline.

Support lateral walls of the primordial pharynx, formed from mesenchyme.

Internal sacs derived from endoderm, contributing to various head/neck structures.

External grooves that separate the pharyngeal arches, develop into ear canal.

Sites where pharyngeal clefts & pouches meet, form tympanic membrane.

Blood vessels within pharyngeal arches, important for development.

Cartilage within pharyngeal arches, forming structures like hyoid bone.

Muscles developing within pharyngeal arches, associated with chewing etc.

Undersized lower jaw, an abnormal development of the pharynx.

A condition causing micrognathia, among other issues.

A genetic disorder causing abnormal development in throat and other systems.

A missing piece on chromosome 22, a key component in DiGeorge syndrome.

Opening between the pharynx & larynx which allows air to enter the trachea.

The hollow space inside the larynx.

Folds within the larynx, crucial for creating sounds.

Cartilage protecting and supporting vocal cords in the larynx.

An abnormal connection between the trachea and esophagus, usually occurring during fetal development.

A condition where the esophagus is completely or partially blocked, often associated with tracheoesophageal fistula.

Incomplete division of the foregut into esophageal and respiratory parts, incomplete fusion of the esophageal folds, or defective tracheoesophageal septum.

Fluid accumulates in the mouth and upper respiratory tract, leading to coughing and choking during swallowing. Contents may reflux from the stomach into the lungs.

The point where something divides into two branches, like the trachea branching into the bronchi.

Narrowing of the trachea, making breathing difficult.

Complete blockage of the trachea, preventing air from passing.

Resection and anastomosis, removing the narrowed portion and reconnecting the normal wider portions.

Early branches of the bronchi that develop from two lateral outpocketings during the fifth week of development.

Further branching of the bronchi, forming the secondary bronchi (right - 3, left - 2) and tertiary bronchi (segmental bronchi) during lung development.

Complete absence of lung tissue, usually affecting one side (unilateral), caused by disruption of blood flow during early fetal development.

Complete developmental arrest of the lung bud, meaning the lung never started to form properly.

Small, underdeveloped lungs, affecting either one or both sides (unilateral or bilateral), caused by various factors like congenital diaphragmatic hernia or changes in growth factors.

Breathing difficulty in newborns, caused by a lack of surfactant, often due to premature birth or intrauterine asphyxia.

A substance that lines the lungs helping them stay open and allow the newborn to breathe. It's like a 'soap' that helps the lungs expand.

Premature birth and prolonged intrauterine asphyxia are the main causes. Both lead to surfactant insufficiency - the substance that keeps the lungs expanded.

Fast breathing, grunting sound with each breath, changes in lip/finger/toe color, widened nostrils with breathing, and chest retractions.

Prevention with corticosteroids before delivery, supplementary oxygen, and artificial surfactant are key elements. For cases with mild symptoms, the baby usually improves within a few days.

A condition where a bronchus fails to develop completely, leading to a blockage in the airway.

A blockage in a lobar bronchus, affecting a larger area of the lung.

A blockage in a segmental or subsegmental bronchus, affecting a smaller area of the lung.

Often caused by intrauterine ischemia (lack of blood flow) after the 16th week of gestation.

Most individuals are asymptomatic, but some may experience recurrent infections, dyspnea (difficulty breathing), coughing, or wheezing.

Can lead to mucus build-up (bronchocele or mucocele), hyperinflation (overexpansion) of the affected lung segment.

Usually diagnosed using a computed tomography (CT) scan or bronchofibroscopy.

Can be treated with thoracoscopic surgery (keyhole surgery), local resection (removing a small part), or lobectomy/segmentectomy (removing a larger part of the lung).

From week 4-7, lung buds form, followed by primary bronchial buds, main bronchi, secondary bronchi, and tertiary bronchi.

From week 5-17, the bronchial tree develops, with tertiary bronchi branching into primary bronchioles and then terminal bronchioles, but no respiratory bronchioles or alveoli are present, making respiration impossible.

From week 16-26, terminal bronchioles divide into respiratory bronchioles, which branch into alveolar ducts, and the mesenchyme becomes highly vascular, making respiration possible.

From 24 weeks to birth, terminal sacs (primitive alveoli) form, capillaries establish close contact for gas exchange, and blood-air barrier forms, enabling survival.

From 8 months to childhood, terminal sacs differentiate into mature alveoli, with well-developed epithelial endothelial contacts, allowing for efficient gas exchange, and alveoli continue to form throughout early adulthood.

Squamous epithelial cells in the alveoli that are responsible for gas exchange.

Rounded secretory epithelial cells in the alveoli that produce pulmonary surfactant, which helps keep the alveoli open.

The main function of the respiratory system is gas exchange, which allows for the uptake of oxygen and the release of carbon dioxide. It also plays a role in smell, filtration, sound production, and waste elimination.

The endoderm, a primary germ layer, develops into the lining of the respiratory system, including the pulmonary epithelium and glands.

The splanchnic mesoderm, a specific type of mesoderm, gives rise to the connective tissue, cartilage, and smooth muscle of the respiratory system.

The respiratory diverticulum is an outpouching from the ventral wall of the foregut that develops into the respiratory system.

Retinoic acid, produced by the mesoderm, upregulates the transcription factor Tbx4 in the endoderm near the respiratory diverticulum, inducing lung bud formation and growth.

The five facial primordia are embryonic structures that develop into features of the face: Frontonasal prominence, maxillary prominences (2), and mandibular prominences (2).

Nasal placodes are thickened areas of ectoderm that develop into the nasal pits, the precursors of the nasal cavities.

Nasal placodes become depressed to form pits. The surrounding mesenchyme proliferates, forming prominences. Nasal pits deepen and form sacs. These sacs grow dorsally, forming the nasal cavity.

The rupture of the oronasal membrane allows communication between the nasal and oral cavities, forming the primordial choanae.

The olfactory epithelium contains specialized olfactory receptor cells, which detect odors and whose axons form the olfactory nerves, connecting to the brain.

The development and apoptosis of an epithelial plug forms the nasal vestibule, the entrance to the nasal cavity.

Congenital arrhinia (absence of nose), polyrhinia (two noses), and proboscis lateralis (rudmentary nasal appendage) are some developmental anomalies of the nasal cavity.

The pharynx, a part of the throat, develops from the primordial pharynx, which is formed from mesenchyme and endoderm.

Micrognathia (small lower jaw) and Pierre Robin syndrome (including micrognathia) can result from abnormal pharyngeal development.

The laryngeal orifice is the opening between the pharynx and larynx, allowing air passage to the trachea.

Each pharyngeal arch contains a unique set of structures: a pharyngeal arch artery (blood vessel), pharyngeal arch cartilage (cartilage), pharyngeal arch muscles (muscles), and pharyngeal arch nerves (nerves).

The six pharyngeal arches are numbered 1 to 6. Each arch has a specific role in development. Arch 1 contributes to chewing, arch 2 to smiling, arches 3 and 4 to swallowing, arch 5 has limited contributions, and arch 6 is involved with speaking.

Pharyngeal pouches give rise to various structures in the head and neck. The first pouch contributes to the middle ear cavity and auditory tube, the second contributes to the palatine tonsil, the third forms the inferior parathyroid glands and the thymus, and the fourth and fifth form the posterior parathyroid glands and the ultimobranchial body.

An abnormal development of the pharynx resulting in an undersized lower jaw, also known as mandibular hypoplasia.

Micrognathia can be caused by conditions like Pierre Robin syndrome, Trisomy 13 (Patau syndrome), and Fetal alcohol syndrome.

The laryngeal orifice changes from a sagittal slit to a T-shaped opening due to the growth of arytenoid swellings towards the tongue.

The thyroid cartilage protects and supports the vocal cords within the larynx.

The larynx plays crucial roles in breathing, producing vocal sounds, and preventing food from entering the trachea and lungs.

The larynx's epithelial lining originates from the endoderm, while its cartilages and muscles develop from mesenchyme in the 4th and 6th pharyngeal arches.

The vocal folds are formed by folds of mucous membrane within the larynx that develop from the laryngeal ventricles.

The epiglottis is responsible for preventing food and drink from entering the respiratory tract during swallowing.

Tracheoesophageal fistula is the most frequent abnormality of the lower part of the breathing system, affecting about 1 in 3000 to 4500 newborns.

Babies with this condition may have excessive saliva, choking when feeding, and regurgitation (spitting up). They may also cough and have trouble breathing due to gastric contents entering the lungs.

Surgery is typically required to repair the abnormal connection and restore normal flow of food and air.

Surgery to widen the trachea and remove the narrowed portion is the primary treatment for tracheal stenosis.

These are the branches that directly branch off from the main bronchi. The right bronchus forms three secondary bronchi, while the left forms two.

These buds give rise to the segmental bronchi, which further divide the airways into the future bronchopulmonary segments. There are ten in the right lung and eight in the left.

Often caused by lack of blood flow (ischemia) in the womb after week 16 of pregnancy.

Usually no symptoms, but sometimes recurrent infections, breathing difficulties (dyspnea), coughing, or wheezing.

Can lead to mucus build-up (bronchocele or mucocele) and overexpansion (hyperinflation) of the affected lung part.

Usually diagnosed by a CT scan (detailed image) or bronchofibroscopy (looking into the airway).

Can be treated by surgery, such as thoracoscopic (small incisions), local resection (removing a small part), or lobectomy/segmentectomy (removing a larger part of the lung).