Respiratory System Flashcards
What are the primary functions of the respiratory system?
Obtain oxygen and remove carbon dioxide
What is the function of oxygen in the cells?
To oxidize glucose to produce energy
Glucose + Oxygen= Energy + CO2 + H2O (cellular respiration)
What are the additional functions of the respiratory tract?
Regulation of Blood pH Filtration of incoming air Hydration and temperature control of incoming air Housing receptors for sense of smell Production of speech Excretion of water and heat
The majority of the respiratory tract minus the alveoli is lined with this epithelium.
Pseudo stratified columnar epithelium
What is cilia?
Cilia is mucous and hairlike projections. Cilia sweep the mucus up toward the pharynx so it can either be swallowed of spit out.
How does mucus protect the body?
By trapping small particles and microorganisms
Why are microorganisms not found in the lower respiratory tract?
Because they are trapped in the mucus that is swept toward the pharynx by the cilia
What does the upper respiratory system consist of?
The nose, nasal cavity, paranasal sinuses, pharynx and tonsils
What is the nose supported by?
Two nasal bones and hyaline cartilage
What are the openings in the nose called?
Nares or nostrils
What is the nasal septum?
It divides the nasal cavity into right and left portions. The nasal cavity opens posteriorly into the nasopharynx
What is the nasal conchae?
It is the 3 pairs of bony projections that project from the lateral walls of the nasal cavities
What is the function of the mucous membrane covering the conchae?
Function to filter, warm and moisten the incoming air
What are the paranasal sinuses?
Air filled cavities which are lined with mucous membrane and open in to the nasal cavity
Where are the paranasal sinuses located?
In certain skull bones that include the frontal, sphenoidal, maxillary, and ethmoidal
What are the functions of the paranasal sinuses?
Warm and moisten incoming air and to resonate vocal sounds
What are the divisions of the pharynx (throat)?
nasopharynx (behind the nasal cavity)
oropharynx (behind the oral cavity)
laryngopharynx (opens in to the larynx and esophagus)
What are the functions of the pharynx?
Form a passageway for air and food
Resonate vocal sounds
House tonsils
What are tonsils?
Tonsils are masses of lymphatic tissue that are found in the pharynx. They function to help protect the body against infection
What are the different tonsils?
Pharyngeal tonsil (adenoid): located in the posterior nasopharynx
Palatine tonsils: Located on the lateral sides of the oropharynx
Lingual tonsils: Located near the pharynx
What does the lower respiratory system consist of?
the larynx, trachea, bronchial tree, alveoli and lungs
Where is the larynx located?
superior to the trachea and inferior to the pharynx
What does the larynx consist of?
- Thyroid cartilage (adam’s apple): composed of hyaline cartilage and forms the anterior wall of the larynx
- Epiglottis: a lid like structure composed of elastic cartilage and serves to close off the larynx during swallowing
- Cricoid cartilage: composed of hyaline cartilage and forms a ring at the base of the larynx
- Vocal cords: composed of skeletal muscle and elastic fibres extending inward from the lateral walls of the larynx and vibrate to produce sound.
What are the functions of the larynx?
- Conducting air in and out of the trachea
- Preventing foreign objects from entering the trachea
- Producing sound
Describe the trachea.
- The trachea is a flexible, cylindrical tube which extends anterior to the esophagus and branches in to two main bronchi
- It contains about 20 C-shaped pieces of hyaline cartilage that function to prevent the trachea from collapsing and obstructing the airway
- The soft tissue at the back of the trachea allows the esophagus to expand as food passes through it
What does the bronchial tree consist of?
- Main bronchi (right and left pulmonary bronchus)
- Lobar bronchi (branch to each lobe of a lung- 3 lobes in right/2 lobes in left)
- Smaller bronchi
- Bronchioles
What are two major structural differences between the right and left main bronchi?
-Right is more vertical then the left
-Right is larger then the left
As bronchioles become smaller they have less cartilage and more smooth muscle
What are the alveoli composed of?
The walls of the alveoli are composed of simple squamous epithelial tissue that is one cell thick
What is surfactant?
A slippery fluid produced by specific cells in the alveoli that reduces the alveoli’s tendency to collapse
Where do the two main blood gases exchange?
The capillaries is where oxygen and carbon dioxide exchanged. This is part of the pulmonary circulation. These gases are exchanged by diffusion
What cavity are the lungs located in?
The thoracic cavity, enclosing the mediastinum. They are superior to the diaphragm and protected by the ribs
What are the superior and inferior portions of the lungs called?
superior: the apex
inferior: base
What is the hilum?
The hilum is a depression on the medial surface of each lung.
The main bronchi, major blood vessels, lymphatics, and nerves enter or leave the lungs through this region
How many lobes does each lung have?
The right lung has 3 lobes and the left lung has 2 lobes. The left lung is smaller due to the location of the heart
What is the serious membrane covering the lungs called?
pleura, the visceral pleura covers the lungs while the parietal pleura lines the thoracic cavity and the space between the two layers is called the pleural cavity
What does the respiratory membrane consist of?
The alveolar wall, capillary wall and their basement membranes
What is atmospheric pressure?
Weight of surrounding air
What is intrapulmonic pressure?
Air pressure within the lungs
What is inspiration?
inhalation, the process of breathing in; occurs when atmospheric pressure is greater than intrapulmonic pressure
What is expiration?
exhalation, the process of breathing out; occurs when intrapulmonic pressure is greater than atmospheric pressure
What is tidal volume?
Tidal volume is the volume of air moved in and out of the lungs with each inspiration and expiration
What is vital capacity?
Vital capacity is the maximum volume of air exhaled after the deepest inhalation
What is residual volume?
Residual volume is the volume of air that remains in the lungs after the maximum exhalation
What is total lung capacity?
TLC is the total volume of air that the lungs can hold. It is the sum of vital capacity and residual volume
What is the anatomic dead space?
The anatomic dead space is the area within the nose, pharynx, larynx, trachea, and bronchial tree. The air in the anatomic dead space does NOT participate in gas exchange
What is external respiration?
External respiration is the exchange of oxygen and carbon dioxide between the alveoli of the lungs and the pulmonary capillaries. It results in the conversion of deoxygenated blood coming from the pulmonary artery to oxygenated blood returning to the pulmonary veins
What is internal respiration?
Internal respiration is the exchange of oxygen and carbon dioxide between the blood capillaries and the body cells. It results in the conversion of oxygenated blood to deoxygenated blood
What is cellular respiration?
Aerobic cellular respiration occurs within the cells and involves the breakdown of glucose in the presence of oxygen to release energy
How is oxygen transported in the blood based on percentages?
2%: dissolved in plasma
98%: as oxyhemoglobin
How is carbon dioxide transported in the blood based on percentages?
7%: dissolved in plasma
23%: as carbaminohemoglobin
70%: as bicarbonate ions
What are two chemical formulas that show how carbon dioxide reacts with water to form bicarbonate ions?
carbon dioxide + water= H2CO3 (carbon dioxide and water forms carbonic acid)
H2CO3= H+ + HCO3 (carbonic acid dissociates to hydrogen ions and bicarbonate ions)
True of False: If CO2 accumulates in the blood MORE carbonic acid forms and breathing becomes more rapid
True
What do the breathing muscles include?
diaphragm that is regulated by nerve impulses from the phrenic nerve and the intercostal muscles that are regulated by impulses from the intercostal nerves
Where are the respiratory centres located?
In the brain
- One of the centres is responsible for the rate and rhythm of breathing
- One of the other centres is important in producing smooth transition from inspiration to expiration and adjusts respirations in special circumstances such as during sleep or exercise
What is the most important stimulus for breathing in a healthy person?
The need to rid the body of excess carbon dioxide
What do chemoreceptors in the brain sense change in?
carbon dioxide and hydrogen ion levels in the cerebrospinal fluid
when these levels increase the respiratory rate and tidal volume increase causing more carbon dioxide to be exhaled
What will emotional anxiety increase?
the respiratory rate and tidal volume
What will temperature affect?
the rate of respirations
increase in temperature will increase respiratory rate
decrease in temperature will decrease respiratory rate
