Chapter 23 Respiratory System Flashcards
Cellular respiration formula
C6H12O6 + 6O2 -> 6CO2 + 6H2O + ATP
Diffusion of blood gasses require:
thin walls + moist surfaces + rich blood supply
Upper respiratory tract (outside the thorax)
- nasal cavity & paranasal sinuses
- larynx & pharynx
Lower respiratory tract (within the the thorax)
trachea, bronchi, bronchial tree, lungs, pleural cavity
vestibule
alar cartilages support nostril
anterior septum formed by
hyaline cartilage
Nasal cavity purpose
to warm & humidify incoming air
Nasal vestibules lined with
- sebaceous & sweat glands
- coarse hairs help filter inspired air
Lung development
diverticulum of the gut
Respiratory epithelium
pseudostratified ciliated columnar epithelium
Nasopharynx
located: btw internal nares and top of soft palate
- auditory tubes
- pharyngeal tonsil (adenoids)
Soft palate
serves as a flap valve btw nasal cavity and pharynx
Oropharynx
located: btw soft palate and hyoid bone
- palatine and lingual tonsils
Laryngopharynx
located btw hyoid and glottis
Larynx (voice box)
- cylinder w/ cartilage
function: surrounds and protects the glottis and trachea
Laryngeal cartilages: thyroid
- Adam’s apple
- large, shield-shaped
Laryngeal cartilages: cricoid
- medium-sized
- ring-shaped
Laryngeal cartilages: arytenoid
- 2
- anchor for vocal ligaments
- triangle-shaped
Laryngeal cartilages: corniculate
- 2
- anchor for vestibular ligaments
- small and looks like corn kernels
Laryngeal cartilages: cuneiform
- 2
- stabilize epiglottis from below
Epiglottis
- sheet of elastic cartilage
- hinged: folds over to cover the glottis
- valve that diverts food to esophagus (protect airway)
False vocal cords
vestibular ligament + vestibular fold
True vocal cords
vocal ligament + vocal fold
True vocal cord specifics
- male cords longer than females
- tension and spacing of cords = sound, pitch, volume
Trachea (windpipe)
- tough, flexible tube, connect larynx to lungs
- lined w/ respiratory epithelium
C-shaped cartilages in trachea
- hyaline cartilage
- connected w/ annular ligaments
- posterior gap
Carina
where trachea divides to form R&L primary bronchi
Tracheostomy
surgical opening in trachea to allow passage of air
Bronchial tree
- Right is longer & aligned with trachea
- degree of compliance increases
- cartilage support decreases
Secondary bronchi
- lobar
- right side: 3
- left side: 2
Tertiary bronchi
segmental
Bronchial tree organization
- bronchi split into bronchioles
- bronchioles branch into respiratory bronchioles
- respiratory bronchioles terminate in several alveoli
Bronchodilation
sympathetic ANS
Bronchoconstriction
parasympathetic ANS
Surfactant
- compound that lowers the surface tension btw surface
- EX: detergents, dispersants, wetting agents
Alveoli
- site of gas exchange
- simple squamous epithelium
- very thin walls
- vascular
What does the elastic fibers in alveoli do?
push air out of segment
What produces surfactant in alveoli?
septal cells
Infant respiratory distress syndrome
- premature babies don’t produce enough surfactant
- alveolar walls stick together = alveolar collapse
- blue baby
How many lobes does the right lung have?
3
How many lobes does the left lung have?
2
Components of mediastinum
- heart, aorta, vena cavae, trachea, root of lung
- esophagus, thymus, CN X, phrenic nerves
Pleural and Pericardial cavities?
- potential space
- btw parietal and visceral
Serous fluid
-surface tension hold membranes together and the lung to the chest cavity
Pneumothorax
- air enters pleural cavity
- serous fluid can no longer maintain pleural contact
- lungs collapse
Sucking wounds
- elastic tissue draws the lung into a dense lump of tissue
- collapse draws air through open wound
Pleural adhesions
-damage to visceral & parietal membranes
(smoking, pneumonia)
-body confused and grows adhesions btw visceral & parietal layers
-painful during deep breaths, body movements
Emphysema
- destruction of alveoli
- chronic obstructive pulmonary disease
- loss of surface area for gas exchange = shortness of breath
Pulmonary embolism
- blood clot in lungs that block pulmonary blood vessels
- Result: infarction/necrosis
Inspiration
-diaphragm contracts
(increases volume of thorax)
-compresses abdominal contests
-pressure decreases (vacuum); air pulled into lungs
Forced inspiration
Muscles used to raise rib cage:
external intercostal, sternocleidomastoid, serratus anterior, pectoralis minor
Expiration
Passive: -elasticity of thoracic wall, alveoli, bronchial tree
Result: rebound of abdominal contents
Forced expiration
- abdominal wall muscles compress gut
- internal intercostal muscles compress rib cage
- decreased thoracic volume: air forced out of lungs
Respiratory centers
pons + medulla oblongata
Mechanoreceptors
lung volume + blood pressure
Chemoreceptors
CO2 + O2 + blood in pH
cough
reflex to protect respiratory tract
respiratory diaphragm
- skeletal muscle
- voluntary control via Phrenic nerve
Autonomic nuclei in medulla oblongata
- pacemaker
- involuntary control via Phrenic nerve
