Chapter 6- The Respiratory System Flashcards
Function of the lungs?
Provides the body with air, gas exchange, thermoregulation, pH balance, immune function
Location of the pharynx and purpose?
Behind the nasal cavity, at the back of the mouth. Common pathway for both air and food destined for the lungs and esophagus respectively.
Location of the larynx and purpose
Lies below the pharynx pathway for air only.
What is another name for the larynx?
Glottis
What structure keeps food out of the respiratory tract?
Epiglottis
Where are the vocal cords located?
Within the larynx maneuvered using skeletal muscle and cartilage
What role does the nose and mouth play in the respiratory system?
The nose and mouth both warm and humidify air before it reaches the lungs. It also functions to remove dirt and particulate matter from the air.
What features of the trachea and bronchi help catch material that has made it past the mucous membranes in the nose and mouth?
Ciliated epithelial cells
Divisions of bronchi
Bronchi> Bronchioles>Alveoli
What allows for the alveoli to not collapse on itself
Alveoli are tiny balloon like structures where gas exchange occurs.
They are covered in a surfactant that lowers the surface tension and prevents them from collapsing on themselves. (During expiration)
What is the name of the membrane that surrounds each lung?
Pleurae
What are the two types of pleura that surround the lungs?
The surface adjacent to the long is the visceral pleura the outer part is the parietal pleura.
Visceral: near the organ
Pleural: outer portion
What is the space between the visceral and parietal pleura?
Intrapleural space
Contains a thin layer of fluid helps lubricate the pleural surfaces
What muscles are used to help with inhalation
External intercostal muscles (one of the layers of muscles between the ribs)
Describe the process of inhalation
The diaphragm and external intercostal muscles are used to expand the thoracic cavity.
As the diaphragm flattens and the chest wall expands outward intrathoracic volume increases.
This increase in intrapleural volume leads to a decrease in intrapleural pressure.
The gas in the lungs is now higher than the pressure in the intrapleural space the lungs will therefore expand in the intrapleural space and the pressure in the lungs will drop. Air will then be sucked in from the higher pressure environment. (The outside world)
Describe the process of exhalation
Relaxation of the diaphragm and intercostal muscles causes the chest cavity to decrease in volume and increase in pressure.
Pressure in the intrapleural is higher so pressure goes down it’s concentration gradient and air is pushed out of the lungs.
During active tasks, we can speed up the process of exhalation by using which muscles?
Abdominal muscles and internal intercostal muscles which oppose the external intercostal muscles and pull the rib cage down. 
What helps the lungs not collapse?
The indirect connection of the lungs to the chest wall.
RV
Residual volume
The amount of air remaining in the lungs after complete exhalation
TLC
Total Lung Capacity
Maximum volume of air in the lungs when one inhales completely
VC
Vital Capacity
The difference between the minimum and maximum volume of air in the lungs (TLC - RV)
TV
Tidal Volume
The volume of air inhaled or exhaled in a normal breath
ERV
Expiratory Reserve Volume
The volume of additional air that can be forcibly exhaled after normal exhalation
IRV
Inspiratory Reserve Volume
The volume of additional air that can be forcibly inhaled after normal inhalation
Where is the ventilation center located and why is it important?
A collection of neurons in the medulla oblongata
These neurons fire rhythmically to cause contraction of respiratory muscles
Sensitive to carbon dioxide concentration
The ventilation center in the medulla oblongata contains what type of receptors? What are they sensitive to
Chemo receptors that are sensitive to carbon dioxide concentration.
What is the condition called where the partial pressure of carbon dioxide in the blood rises
Hypercarbia/Hypercapnia
What changes happen in the respiratory rates when the partial pressure of carbon dioxide in the blood rises
In order to release carbon dioxide from the body and decrease its partial pressure in the blood respiratory rate increases so that more carbon dioxide is exhaled causing carbon dioxide levels in the blood to fall.
Hypoxemia
Low oxygen concentration in the blood
Extended periods of hypoventilation would lead to increased levels of what gas?
Carbon dioxide.
Medulla Oblongata overrides and jump starts breathing.
Extended periods of hyperventilation would lead to a decrease in which gas?
Carbon dioxide
Inhibit ventilation
An increased respiratory rate would have what effect on pH and CO2 levels
⬇️ CO2
A decreased respiratory rate would have what effect on pH and CO2 levels?
⬆️ CO2
Each alveolus is surround by ______
A network of capillaries
Capillaries bring oxygenated/deoxygenated blood to the alveolus? From what structure?
Deoxygenated from the pulmonary arteries
Where did the pulmonary arteries originate from in the heart?
Right ventricle
The walls of the alveoli are how many cells thick
One
What gas exchange occurs at the alveoli
Carbon dioxide is moved from the blood into the lungs and oxygen is moved into the blood
The oxygenated blood returns to the _________ of the heart via the ________
Left atrium
Pulmonary veins
What is the driving force for gas exchange at the alveoli?
Pressure differentials
Is energy required for the transfer of gas at the alveoli?
No energy is required for a gas transfer at the alveoli. Carbon dioxide and oxygen move down there concentration gradient from the blood to the lungs and vice versa.
Thermoregulation
Regulation of body temperature. Regulated by vasodilation and vasoconstriction.
Vasodilation vs Vasoconstriction
Capillaries expand, more blood can pass, larger amount of thermal energy dissipated.
Capillaries shrink less blood can pass… thermal energy conserved
In what ways does the respiratory system (nose) display its immune function?
The hairs in the nose trap particulate matter and infectious particles. The nose also contains an enzyme called lysozyme that attacks the peptidoglycan wall of grandpa positive bacteria.
In what ways does the respiratory system (lungs) display immune function
Mucus traps particulate matter and larger invaders.
Cilia propel mucus up the respiratory track to the oral cavity (mucocililary escalator).
The Alveoli contain numerous macrophages which engulf and digest pathogens and signal to the rest of the immune system if there’s an invader.
Mucosal surfaces also contain IgA antibodies that help to protect against pathogens that contact the mucous membranes.
Mass cells also populate the lungs these cells have antibodies on their surfaces which attach to substances which releases inflammatory chemicals into the surrounding area to promote immune response.
Bicarbonate buffer equation
CO2 + H2O ➡️⬅️ H2CO3➡️⬅️H+ +HCO3-
What is the optimal pH level of the body
Between 7.35 and 7.45 
When the body pH is acidic the brain sends signals to _________ respiratory rate.
Increase respiratory rate
Increase in blood CO2
When the body pH is basic the brain sends signals to _________ respiratory rate.
Decrease respiratory rate
Decrease CO2
Blood pH and respiratory rate
Respiratory rate and blood CO2
pH⬆️respiratory rate⬇️
respiratory rate ⬆️ CO2 ⬇️
