Module 9 Flashcards
What are the two phases of breathing?
Inspiration (draws oxygen rich air into lungs)
Expiration (forces oxygen poor air out of lungs)
What are the five functions of the respiratory system?
Gas exchange
Gas conditioning
Sound production
Olfaction
Defense
What does external respiration involve?
External respiration refers to the exchange of gases between the air and blood. Inspired oxygen moves across the cellular membranes of the … in the lung and its associated … into the blood, while waste carbon dioxide moves in the opposite direction out of the body.
alveolus, capillaries
What does internal respiration involve?
Similar mechanism that exchanges gases between blood and cells of body.
What is the point of gas conditioning?
Warming, conditioning, cleansing gases entering lungs to prevent damage
Where does gas conditioning occur? What does it involve? How is it cleansed?
- Nasal cavities and paranasal sinuses
- Air is swirled around to become warm and humidified
- Inhaled air is cleansed of particulate matter through contact with mucosal lining of respiratory epithelium
What does production of sound (ex. singing/speech) occur by?
forceful expiration of air through vocal cords in larynx, causing them to vibrate
Where does olfactory epithelium cover?
Top of nasal cavity
Where are receptors for smell located?
Within olfactory epithelium
How does olfaction work?
When air is inhaled in the nasal cavity, airborne molecules dissolve in mucus which lines cavity and stimulates receptors.
Signals from these receptors travel to the brain through CN I, causing sense of smell.
What helps trap particles and microorganisms from entering nose and respiratory system (3)?
- Coarse hairs of nostrils
- Ciliated cells of respiratory epithelium
- Mucus lining
The epithelium of the respiratory tract is … meaning all cells are attached to the … but only some reach the surface
pseudostratified
basal lamina
The apical surface of the pseudostratified epithelium is covered in … which are small fingerlike projections extending from the cell
Cilia
What are two functions of cilia?
- increase surface area for conditioning air (filtering, humidifying, moistening)
- function to trap inhaled particles and microorganisms caught in mucus, and sweep them back up the respiratory tract and out through nose and mouth
What cells are interspersed throughout the pseudostratified epithelium?
Goblet cells
What do goblet cells produce? What are two functions of what it produces?
Mucus
- protective layer over epithelium & traps particulate matter or microorganisms that may be inhaled
- provides moisture to humidify air before reaching lungs
What are two regions of respiratory system?
Conducting Portion
Respiratory Portion
- Nose and nasal cavity
- Paranasal sinuses
- Pharynx
- Larynx
- Trachea
- Primary, secondary, and tertiary bronchi
Are part of what portion?
Conducting
- Respiratory bronchioles
- Alveolar ducts
- Alveolar sacs
- Alveoli
Are part of what portion?
Respiratory
What does the conducting portion do? Is oxygen absorbed into blood here?
Conduct inhaled air from outside world to lung tissue. Conducts air from lungs to outside world. This is where humidification and trapping of debris occurs. No oxygen is absorbed into blood in this region as the walls of organs are too thick.
What is the function of the respiratory region?
- transfers gases between lungs and pulmonary capillaries
What are pulmonary capillaries? What do they do?
Terminal structures within lungs with thin walls to facilitate movement of gases from air to blood & vice versa
What are a collection of air filled spaces within bones of the skull communicating with the nasal cavity called?
Paranasal Sinuses
What are the four types of paranasal sinuses (each paired)?
Frontal sinus
Maxillary sinus
Ethmoid sinus
Sphenoid sinus
What do paranasal sinuses help with? (3)
Aid in conditioning of air, defence against pathogens, resonance chambers for speech
What are paranasal sinuses lined with?
Respiratory tract epithelium
What are the first line of defence against invading pathogens and debris, trapping them in coarse hairs and mucus?
Nose and nasal cavity
Air enters the … (openings of nostrils) and is passed into the nasal cavity where it is conditioned.
Vestibules
What are the six boundaries of the nasal cavity?
Roof - ethmoid bone
Floor - hard palate (roof of mouth)
Medial wall - makes up nasal septum (composed of vertical bones in skull and separates two halves of nasal cavity)
Lateral walls - contain nasal conchae - create turbulence in air as it passes through, allowing conditioning and catching debris
Anterior border - made of nares/nostrils (opening between nose and nasal cavity)
Posterior border - opening (choanae) to nasopharynx, where nasal cavity connects to pharynx
What is the nasal cavity mostly covered in?
Respiratory tract epithelium
What is the roof of the nasal cavity lined with?
Olfactory epithelium (contains sensory receptors for smell)
What is the olfactory epithelium composed of (2)?
- Pseudostratified ciliated columnar epithelium
- bipolar olfactory receptor neurons
What is the name of the muscular tube that connects nasal cavity and larynx in respiratory system?
Pharynx
What does pharynx also connect (in digestive system)?
Oral cavity with esophagus
What are the three components of the pharynx?
nasopharynx
oropharynx
laryngopharynx
What parts of the pharynx are part of both the respiratory and digestive system?
oropharynx
laryngopharynx
What is nasopharynx lined with?
RTE (mostly)
What is oro- and laryngopharynx lined with? Why?
Stratified squamous epithelium
Need for durability when swallowing food
What does the eustachean tube connect?
Middle ear to nasopharynx
What’s the organ that produces sound also known as the voice box?
Larynx
What is larynx made of?
Variety of cartilages, ligaments, and associated muscles
Where does larynx sit?
Anterior to esophagus, connecting pharynx with trachea and preventing food from entering trachea
What are the three main cartilages of larynx?
Epiglottis
Thyroid Cartilage
Cricoid Cartilage
What is the large spoon shaped elastic cartilage that functions to prevent food from passing into the trachea? During swallowing, it flips downwards and covers the opening of the trachea.
Epiglottis
What type of cartilage is epiglottis made of?
Elastic
What is the shield shaped hyaline cartilage that provides attachment for many muscles and vocal cords?
Thyroid cartilage
What is the complete ring of hyaline cartilage, that is narrow anteriorly and broad posteriorly, and also serves as attachment for muscles and vocal cords?
Cricoid cartilage
What are thyroid and cricoid cartilage made of?
Hyaline cartilage
What are vocal cords? What are they attached to?
Small ligaments attached to laryngeal cartilages
When vocal cords vibrate? How are different sounds made?
Sound produced. Different sounds made by altering tension of cords.
What are true vocal cords (ligaments that produce sound) protected by?
Membranous flap called false vocal cords
Which level does trachea extend from larynx at?
T4/T5
What is the junction where the trachea splits called?
Carina
What is the main function of the trachea?
Conduction of air to lungs
What is trachea made of? What do these function do to? How many? Whats special about posterior?
15-20 cartilaginous rings
Keep airway open
Incomplete posteriorly
What are cartilaginous rings of trachea connected posteriorly by?
Trachealis muscle
What are the three histological layers of the trachea?
Mucosa
Submucosa
Adventitia
What part of layer of trachea is lined with RTE to clear any debris or pathogens that make it into the lower respiratory tract?
Mucosa
What part of layer of trachea is made of loose (areolar) connective tissue, containing larger vessels and nerves, as well as mucus secreting glands?
Submucosa
What is the outer layer of connective tissue surrounding the trachea? This layer also encloses the C-shaped cartilaginous rings made of hyaline cartilage.
Adventitia
Splitting of the trachea results in two … …, left and rights, which have the same functional and histological features as the trachea.
primary bronchi
Each primary bronchus enters its respective lung on the medial side at the …
hilus
How are the right and left bronchus different from eachother?
Right is wider, shorter, more vertical
What is the end of the conducting portion characterized by? What are these called?
Bronchi dividing into smaller and smaller tubes. Secondary bronchi, tertiary bronchi, terminal bronchioles
How thick is the respiratory portion on bronchial tree?
One cell layer thick - gases can cross easily
The respiratory portion makes up a majority of the … within both lungs.
lung tissue
Which lung is larger? Why?
Right larger, due to positioning of heart
How many lobes does right lung have?
Three
What are the lobes of right lung called?
Superior, middle, inferior
How many fissures does right lung have? What are they called?
Two
Horizontal fissure
Oblique fissure
How many lobes does the left lung have? What are they called?
Two
Superior and inferior lobes
What does the superior lobe contain?
Cardiac notch - depression on anterior border of left lung that accommodates the space taken up by the apex of the heart
What is the small outward facing process that covers the heart called (on left lung)?
Lingula
How many fissures does the left lung have? What is it called?
One
Oblique fissure
What is the most superior point of the lung called? Where does it sit?
Apex
Just above first rib
The lung sits superiorly to the diaphragm, a dome-shaped skeletal muscle. The base of the lung is known as the … surface.
Diaphragmatic
What is the name of the surface that curves around the lateral aspect of the lung?
Costal
What is the name of the medial surface of the lung? What does it contain?
Mediastinal
Hilum - entry and exit points for all vessels and airways at a structure
What is the name of the continuous membrane that forms a sac around each lung?
Pleura
What does the pleura secrete? What does it act as?
Pleural fluid
Acts as lubricant, allowing visceral pleura of lung to slide freely on parietal pleura of thoracic wall during inflation and deflation
What is the outer serous membrane attached to the walls and floor of thoracic cavity around lungs?
Parietal pleura
What is a serous membrane attached to the surface of the lung that is continuous with the parietal pleura at the hilus?
Visceral pleura
What branches from the terminal bronchioles. These are the first structures to contribute to gas exchange in the lungs.
Respiratory bronchioles
What are the respiratory bronchioles made of?
Thin walled ducts with simple ciliated cuboidal epithelium. Continue to branch ending with alveioli
What is the functional unit of the lung where gas exchange takes place?
Alveoli
What are alveolus surrounded by to maximize amount of oxygen going through body and carbon dioxide leaving body?
Capillaries
