Respiratory Flashcards
Upper Respiratory System
- Bone and nasal cavity
- nasopharynx
- sinuses
Lower Respiratory System
- larynx
- trachea
- bronchi
- alveoli of lungs
Respiratory system is functionally divided into what?
- conducting: air passages that lead to sites of respiration and condition air (moisten air with mucous or water)
> nasal cavities, nasopharynx, larynx, trachea, and bronchi - respiratory: sites of gas exchange
> respiratory bronchioles, alveolar ducts, sacs and alveoli, and blood vessels that enter the lung with the bronchi
Nasal cavity
- superior wall has olfactory region
- vestibule: enclosed by flexible tissues (elastic cartilage)
- external nares = nostrils
- nasal septum: divides right and left nasal cavities (not pictured)
- floor has soft palate (muscle) and hard palate (bone)
- lateral wall has superior, middle, and inferior nasal conchae
> bones that poke into nasal cavity -> create a lot of surface area for us to moisten and condition that air before we start breathing it
Nasopharynx
- lies posterior to nasal cavity and soft palate; is respiratory
- lined by respiratory epithelium
Oropharynx
- it’s posterior to the oral cavity; respiratory and digestive functions
- food particles and air particles both travel thru here
Laryngopharynx
- lies posterior to the larynx; respiratory and digestive regions
Larynx
- a passageway for air that connects pharynx to trachea
- consists of epiglottis, thyroid cartilage, cricoid cartilage, and arytenoid cartilages
Epiglottis
- folds back over glottis (hole leading into the larynx) during swallowing to prevent food or liquid from getting into airway
- filled w/ elastic tissue and allows it to flop over and back every time we swallow
Thyroid cartilage
- forms laryngeal prominence
- serves as an attachment for some vocal muscles and ligaments
Cricoid cartilage
- forms a complete ring
- connects w/ thyroid cartilage
Arytenoid cartilages
- (paired) are involved with opening and closing the glottis
Vocal folds
- vocal cords extend btw thyroid and arytenoid cartilages
- involved in voice production
- can open or close to let air in or out
- tension on vocal folds controls pitch of voice
- false vocal cord = superior
- true vocal fold = inferior. Filled w/ muscle or ligaments. Can tense or relax in order to produce diff pitches of our voice
Intrinsic laryngeal muscles
- regulate tension in vocal folds
Forced closure
- coughing
Speaking
- air bumps up against these things to produce pitch
Normal respiration
- just breathing
Forced respiration
- breathing heavy
Extrinsic muscles of larynx: Part A
- muscles of the tongue and soft palate push bolus (mushy food) into the oropharynx
Extrinsic muscles of larynx: Part B
- elevates soft palate, sealing off nasopharynx; elevate larynx, which enlarges pharynx
- squeezing larynx all the way up against our oropharynx to make the hole bigger to get more food in
Extrinsic muscles of larynx: Part C
- pharyngeal constrictors contract sequentially, squeezing bolus into esophagus
- epiglottis is closed
Extrinsic muscles of larynx: Part D
- bolus moves down esophagus via peristalsis
Extrinsic laryngeal muscles
- raise the larynx for swallowing
Trachea
- windpipe
- connects larynx to primary bronchi
- supported by C-shaped cartilages — helps keep it open
Bronchi
- trachea splits into bronchi
- primary bronchi: originate outside of lung
- secondary bronchi: (divide inside the lung) — sometimes called pulmonary bronchi
Respiratory tract
- primary bronchus
- secondary bronchi
- tertiary bronchi
- bronchioles branch from tertiary bronchi — no cartilage anymore
- terminal bronchioles: last phase of conducting resp system
- respiratory bronchioles: have air pockets that you can actually breathe out of
- alveoli
Bronchopulmonary tree
- tertiary bronchi divide into bronchioles -> bronchioles divide into terminal bronchioles -> terminal bronchioles divide into respiratory bronchioles -> alveolar ducts branch from respiratory bronchioles -> terminal branches are alveoli
Alveoli
- pockets of alveolar epithelium
- gas exchange: occurs btw epithelium of alveolus and adjacent capillary
“Respiratory” Epithelium
- pseudostratified, ciliated, columnar epithelium with numerous goblet cells
- not where respiration occurs
- pseudostratified: all cells contact basement membrane but not all lead to surface
- goblet cells: produce mucus that protects respiratory passages
- ciliated: have cilia on surface that conduct mucus upward
> move and beat in a rhythmic way
Alveolar epithelium
- main component is the capillary
- also type 1 pneumocytes that separate air cavity from capillary, form most of alveolar wall, and simple squamous
- type 2 pneumocytes secrete surfactant (helps us reduce air pressure in our lungs so that they don’t collapse
- macrophage/“dust cell”: eat things that make it down to our resp system
Right lung: 3 lobes
- superior lobe
- inferior lobe
- middle lobe
- oblique fissure: separates superior and inferior as well as inferior and middle
- horizontal fissure: separates superior and middle lobe
Left Lung: 2 lobes
- superior lobe
- inferior lobe
- oblique fissure: separates superior and inferior lobe
Diaphragm
- the primary muscle of respiration (especially inspiration): contraction increases volume of thoracic cavity (think syringe)
- teaches to bottom of rib cage
- flattens it every time it contracts
External intercostals
- assist in inspiration
- breathing in
- pull ribs up and out when they contract
Internal intercostals
- assist in expiration (but usually just elastic recoil)
- breathing out
- pull lungs back down in the opposite direction
Accessory muscles of respiration
- only involved in breathing when the depth and frequency of respiration needs to increase; usually pull up on ribs or upper thoracic cage:
> sternocleidomastoid, serratus anterior, pectoralis minor, scalene muscles
> used when we need to breath in
> used more when we’re sick & have a hard time breathing