larynx and trachea Flashcards
- develops from the 9 endoderm of laryngotracheal tube (in its cranial end)
o located in the anterior neck (C3-C6 vertebrae)
larynx or trachea
larynx “voice box”
o connects pharynx (oropharynx) to trachea
o serves as the “sphincter” or “valve” during swallowing, guarding the air passage
larynx or trachea?
larynx
o from myoblast in 4th and 6th pairs of pharyngeal arches which is supplied by laryngeal branches of the vagus nerves (cranial nerve X)
larynx cartilage
laryngeal from mesenchyme (derived from neural crest)
o from proliferation of mesenchyme of laryngotracheal tube
o converts primordial glottis (slit-like aperture), into a T-shaped laryngeal inlet
paired arytenoid swellings
o from the caudal part of the hypopharyngeal eminence (from 3rd and 4th pharyngeal arches)
o in contact with soft palate
epiglottis or larynx
epiglottis “guardian of the airways”
Inferior surface till vestibular folds (false vocal cords)
supraglottis or glottis (middle)
supraglottis
unpaired laryngeal cartilages
thyroid, cricoids, epiglottis
paired laryngeal cartilage
arytenoids, cuneiform, corniculate
o Pearly white
o Origin:
• anterolateral edges of the rima glottidis
true or false vocal cord?
VOCAL FOLD (TRUE VOCAL CORDS) “paired”
3 layers of vocal fold
Mucosa (5 layers)
Lamina propia (3 layers)
Vocalis muscle
Source of sound producing audible vibrations
Sphincter of larynx
mucosa or lamina propia
overlying mucosa
shaped of rima glottis during original breathing and forced respiration
o ordinary breathing: narrow and wedge shaped
o Forced respiration: wide and trapezoidal in shape
o Pink in color
o Extends between thyroid and arytenoid cartilage
o protective in function
true or false vocal cords
VESTIBULAR FOLDS (FALSE VOCAL CORDS)
o 16-20C shaped cartilages (hyaline cartilage) supported by the trachealis muscle
o extending from the larynx (at C6 vertebra) into the thorax
TRACHEA (WINDPIPE)
o Formed by laryngotracheal diverticulum during its separation from the foregut.
TRACHEA OR LARYNX
TRACHEA (WINDPIPE)
• sternal angle or the T4–T5 IV disc
SIZE OF TRACHEA IN ADULT AND INFANT
adult: 2.5 cm in diameter
infant: diameter of a pencil
Terminal Bronchioles
- smallest conducting bronchioles
- 0.5mm diameter
- Last segment of conduction portion of respiratory tract
terminal or repiratory
terminal bronchioles
- characterized by scattered, thin-walled outpocketings (alveoli)
terminal or respiratory bronchus
respiratory
notes to remember
Respiratory bronchiole (gas exchange) -> alveolar ducts -> alveolar sacs (main chamber for gas exchange)
- the largest of the cartilages; its superior border lies opposite the C4 vertebra.
thyroid or epiglottic cartilage
Thyroid cartilage
“adam’s apple”
a heart-shaped cartilage covered with mucous membrane
epiglottic cartilage
- closes the laryngeal inlet as a protective mechanism during swallowing
sphincters
o flat gland with flask-shaped lobes
o primary lymphoid organ
o After puberty, is replaced by fat
thymus gland
- depressors of the hyoid and larynx
infrahyoid or suprahyoid muscles
infrahyoid muscles
- elevators of the hyoid and larynx
infrahyoid or suprahyoid muscles
suprahyoid muscles
- the first and largest branch of the arch of the aorta
BRACHIOCEPHALIC TRUNK
what nerve of thorax
o 8-10 rootlets from medulla of brainstem
vague (CN XI)
o Anterior rami of C3-C5 nerves
vague (CN XI) OR PHRENIC
PHRENIC
o Anterior rami of T1-T11 nerves
Phrenic or intercostal
intercostal
o VOICE HOARSENESS may result because one vocal fold cannot approximate the other
Unilateral or Bilateral
Unilateral
o LOSS OF VOICE
Unilateral or Bilateral
bilateral
add ons: palate
supported by bone, is the hard palate (anterior); the unsupported posterior part is the soft palate.
common passageway for food and air
pharynx or nose ?
pharynx (throat)
air ->nasopharynx-> oropharynx->laryngopharynx->larynx
lie at the base of the tongue.
lingual tonsil
smallest of the conducting passageways
bronchioles
the balance of the lung tissue that is mainly elastic connective tissue that allows the lungs to recoil passively as we exhale.
stroma
Alveolar macrophages “dust cells”
wander in and out of the alveoli picking up bacteria,
lipid (fat) molecule which coats the gas-exposed alveolar surfaces and is very important in lung function.
surfactant by cuboidal cells
Respiratory capacities are measured with– in which the volumes of air exhaled can be read on an indicator, which shows the changes in air volume inside the apparatus.
spirometer
respiratory sounds
Vesicular breathing sounds occur as air fills the alveoli, and they are soft and resemble a muffled breeze.
Neural centers that control respiratory rhythm and depth
medulla: ets the basic rhythm of breathing, contains a pacemaker. EXPIRATION
PONS:smooth out the basic rhythm of inspiration and expiration by medulla
normal respiratory rate
eupnea (12 to 15 respirations/minute.)
