5a Anatomy Of The Respiratory System Flashcards
Why do we respire?
To bring oxygen to our tissues and cells
To remove carbon dioxide
Why do we need oxygen?
For chemical reactions that transform food into energy
How is oxygen distributed?
By the respiratory and cardiovascular systems
What effect will being in an anoxic environment have on brain cells?
Rapid severe brain damage
Brain cell death within 5 minutes
Where does gas exchange occur?
In the alveoli of the lungs
If not for gas exchange, what are the other organs in the respiratory system good for?
To purify, humidify and warm the incoming air before reaching the lungs
What organs constitute the upper respiratory tract?
Nasal cavity
Nostril
Larynx
Oral cavity
Pharynx
What organs constitute the lower respiratory tract?
Trachea
Right and left primary bronchi (bronchus)
Right and left lungs
Diaphragm
What are the main respiratory organs from superior to inferior?
Nose
Pharynx
Larynx
Trachea
Primary bronchitis
2 and 3 bronchioles (secondary and tertiary)
Alveoli
How does air enter the body?
Through the nostrils of the nose and into the nasal cavity
How id the nasal cavity divided?
In half, by the nasal septum
What lines the nasal cavity and its function? Specific
Mucosa membrane
Pseudo-stratified ciliated columnar epithelium
Function: moisten air
trap and push incoming foreign particles to the throat to be swallowed and not respired
Destroy bacteria chemically
How does the nasal cavity warm incoming air?
Network of thin-walled veins warm incoming air
How many nasal conchae are there and where are they located?
3
In the nasal cavity
What do nasal conchae do?
Superior concha houses olfactory receptors
Increases air turbulence within the cavity
What are paranasal sinuses?
Cavities within the frontal, sphenoid, ethmoid and maxillary bones surrounding the nasal cavity
What is the purpose of paranasal sinuses?
Lighten the skull
Act as resonance chambers for speech
Produce mucus
What separates the nasal cavity from the oral cavity? Describe.
The palate
Hard palate: anterior portion, supported by bone
Soft palate: posterior portion, unsupported
Why do our noses run in cold weather?
From the overproduction of mucus that is produced to keep in the incoming air moist and warm
What is the pharynx?
Referred to as throat
Passageway from nasal cavity to larynx
Muscular
What are the regions of the pharynx? List from superior to inferior
Nasopharynx: region immediately behind nasal cavity
Oropharynx: region behind the mouth/oral cavity
Laryngopharynx: region attached to larynx
What do the oropharynx and laryngopharynx have in common?
Common passageway for air AND food
What is the function of the pharyngotympanic tubes?
Opens from the nasopharynx to keep the pressure in the middle ear the same as the pressure in the nasopharynx
Where are the tonsils located?
In the pharynx
What are tonsils?
Clusters of lymphatic tissue that protect the body from infection
What are the 3 types of tonsils and where are they located?
Pharyngeal tonsils (adenoid): 1 tonsil, located in nasopharynx
Palatine tonsils: 2 tonsils, located in the oropharynx at the end of the soft palate
Lingual tonsils: 2 tonsils, located at the base of the tongue
What and where is the larynx located?
Known as voice box because it contains vocal cords
Inferior to the pharynx
What are the functions of the larynx?
Routes air and food into proper channels
Vocalisation
What is the larynx made of?
8 rigid hyaline cartilages
Which of the hyaline cartilages that make up the larynx are the biggest?
Thyroid cartilage (Adam’s apple)
Where is the epiglottis found?
In the larynx
What is the epiglottis made of?
Elastic cartilage
What is teh function of the epiglottis?
Protects the superior opening of the larynx known as the glottis
Directs food to the esophagus and routes air to the trachea
How does the epiglottis control/direct food and air?
The passage of food in the larynx pushes down the epiglottis (closes it) and covers the opening of the trachea, forcing the food down the esophagus
What do the vocal folds do?
Vibrate with expelled air resulting in voice!
What is the glottis?
Not really related to epiglottis
Includes the vocal cords and the opening between the vocal cords
What is the trachea?
Aka windpipe
4 inch long tube that connects to the larynx
Walls are reinforced with c-shaped rings of hyaline cartilage
Why is the trachea reinforced with hyaline cartilage?
To prevent the trachea from collapsing and to hold it open for the passage of air
(Air cant push its way down like food in the esophagus)
What is the trachea lined with and what does it do?
Ciliated mucosa
They beat continuously in the opposite direction of incoming air to expel mucus loaded with dust and other debris
Where does the mucosa oof the trachea come from?
Goblet cells
What does the trachea divide into?
Divides into 2 primary bronchi
What is the hilum?
The “root” of the lung
Where does each main bronchus enter the lung?
At the hilum
Is there a difference between the right and left primary bronchus?
Right: wider, shorter, straighter
Due to placement and inclination of the heart
What do the primary bronchi divide into?
Secondary bronchi
Tertiary bronchi
Bronchioles (terminal bronchioles)
How many lobes do the right and left lungs have?
Right: 3
Left: 2
What space do the lungs occupy in their corresponding cavity?
Almost entire space available in the thoracic cavity except for the central mediastinum (heart)
What are alveoli?
Makes up the majority of lung, simple squamous epithelium where gas exchange occurs
What are stroma?
Elastic connective tissue allowing lungs to expand and recoil as we breathe
Is the pulmonary artery oxygen rich or poor?
Poor
Is the pulmonary vein oxygen rich or poor?
Rich
Is the pulmonary trunk oxygen rich or poor?
Poor
Describe the function/physiology of the pulmonary trunk.
Carries oxygen poor blood from the right ventricle of the heart to the lungs for gas exchange
To do this, the pulmonary trunk splits into the right and left pulmonary arteries and provides the oxygen poor blood to lungs
Oxygen rich blood returns via pulmonary vein
What is the pleura?
Serous membrane lining the lungs and a portion of the thoracic cavity
What are the parts/layers of the pleura?
Visceral pleura: least superficial, covers the lung directly
Pleural cavity: space in between visceral and parietal pleura, filled with serous fluid
Parietal pleura: most superficial, attaches to the chest wall, no direct contact to lung
What occurs at the respiratory zone?
It’s the site of gas exchange, precise area
What are conducting zone structures?
All other respiratory passages
What are some respiratory zone structures?
Respiratory bronchioles
Alveolar ducts
Alveolar sacs
Alveoli
Respiratory membrane
In that order
What is the respiratory membrane?
Air blood barrier of alveolar wall and capillary wall
Are individual alveoli connected? Why or why not?
Yes, by alveolar pores
Connects neighbouring sacs as a bypass for when bronchioles are blocked
What are alveolar pores attached to and attaching?
Attaching: neighbouring alveoli
Attached to: pulmonary capillaries
Describe alveolar walls. Composition?
Thin, simple squamous epithelium
No mucosa
Permits gas transport into and out of the blood
What are the parts of the respiratory membrane? Specify location.
Alveolar epithelium: closest to alveolar wall
Capillary endothelium: closest to capillary wal
Fused basement membranes: in between
What does a surfactant secreting cell do and why?
Secretes surfactant
Coats gas-exposed alveolar surfaces
Lowers adhesion/cohesion factors to lower surface tension (allow expansion of alveoli)
How does gas cross the respiratory membrane?
By diffusion
What do alveolar macrophages do?
Add protection by picking up bacteria, carbon particles and other debris
What type of cells are surfactant secreting cells?
Cuboids surfactant secreting cells
