respitory Flashcards
(25 cards)
What is the main purpose of the structure of the respiratory system?
The structure of the respiratory system allows the efficient flow of air into and out of the lungs so that gas exchange can occur between the air and the blood.
what is the function of cilia?
The function of cilia is to sweep the dirty mucus up the trachea and into the
throat.
How does the respiratory system protect itself from dirt and microbes?
The nasal cavity and upper airways have a mucous lining with goblet cells that produce sticky mucus to trap dirt and microbes before they reach the lungs.
what happens in the nasal cavity?
Air enters the body through the mouth
and nose. The lining of the nose and nasal cavity is lined by mucous membranes.
As the air passes over the membranes, it is warmed and humidified.
There are also hairs and mucus lining the nose. These trap debris, preventing it from reaching the lungs.
describe mouth as a respiratory organ
The mouth can also serve as an alternate entry point for air. The oral cavity plays a minor role in respiration but is essential for speech and swallowing.
If the nasal passages are blocked,
breathing through the mouth becomes
essential.
What is the role of the pharynx and epiglottis in the respiratory system?
-The pharynx, or throat, is the region from the nasal cavity to the top of the trachea and oesophagus.
- Air travels through it before being diverted into the trachea by the epiglottis.
- During inhalation the epiglottis covers the oesophagus, guiding the air into the trachea; when swallowing, the epiglottis covers the larynx, preventing food from entering it
structure and function of larynx
The larynx is a cartilage structure joining the pharynx and trachea.
The larynx contains the vocal cords, which are mucous membranes that are able to vibrate as air passes over them.
In order to produce voice, the lungs blow air against vocal folds in the nearly-closed position. Air pushes through the very small space between
them and in so doing, makes the covering of the vocal folds, known as the mucosa, vibrate.
structure and function of trachea
- it carries the air into and out of
the lungs. - it is made up of C-shaped cartilage rings that hold the structure open, ensuring air can always pass through it.
-At its base, the trachea splits into two branches, one branch taking air into each lung
structure of bronchi
At the end of the trachea, the structure
splits into two primary bronchi, one for each lung. These then split further into secondary bronchi which take the air into each lobe of the lung. The secondary bronchi continue to divide, forming tertiary bronchi.
The bronchi are made up of C-shaped
cartilage rings.
structure of bronchioles
When the tertiary bronchi divide, they
form smaller airways called bronchioles, which continue to split until they end in millions of terminal bronchioles.
-made up of smooth muscle and elastin, allowing the bronchioles to control the flow of air in the lungs, expanding when the body needs more oxygen.
alveoli
Tiny air sacs at the end of the bronchioles
Each alveolus is surrounded by a network of blood capillaries. This is where gases move between the blood in the capillaries and the air in the alveoli.
how many lobes does lung have
left: 2
right: 3
what is the visceral pleura
a membrane that covers
the surface of the lungs
parietal pleura
a membrane that lines the inside of the
chest
structure/ function of ribs
form the framework of the ribs
structure/ function of diaphragm
Muscle between the lungs and abdomen, contracts and flattens
downwards to increase volume in the chest cavity for the
exchange of gases
structure/ function of intercostal muscles
Muscles between the ribs to move the ribcage upwards and outwards increasing volume in the chest cavity when breathing
define and explain ventilation
the process by which air is taken into and out of the lungs. air flows from places of high pressure to places of lower pressure therefore air flows in and out of lungs due to differences in air pressure.
the diaphragm and intercostal muscles work together to change the volume – and therefore pressure – of the lungs, resulting in airflow into or out of the lungs.
define inspiration
The process of taking air into the lungs is called inspiration, or inhalation.
define expiration
Breathing out is called expiration, or exhalation.
explain the steps of inspiration
- the intercostal muscles contract, moving the rib cage upwards and outwards. diaphragm contracts, extending chest cavity downwards.
- lung volume increases
- air flows from higher pressure to lower pressure in the lungs
explain the steps of exspiration
- ribcage moves down and inwards, diaphragm relaxes pushing up into the chest cavity.
- lung volume decreases
- air flows from higher pressure in the lungs to lower pressure outside.
why are the lungs suited for gas exchange?
- The alveoli give the lungs a huge internal surface area, so larger amounts of gases can be exchanged in shorter time.
- Each alveolus is well supplied with blood vessels, so that as much blood as possible is close to the air in the
alveolus. The continuous flow of blood helps to maintain a difference in concentrations of oxygen and carbon
dioxide between the blood and the air in the lungs. - walls of the alveolus is very thin, so that gas molecules do not have far to travel when moving into or out of the blood
explain the process of gas exchange
- pulmonary artery to the lungs brings deoxygenated blood to the capillaries.
- co2 from the blood diffuses from the higher concentration in the blood to the lower concentration in the air. in the alveolus
- oxygen diffuses from the higher concentration in the air in the alveolus to the lower concentration in the blood
- oxygenated blood leaves the capillaries of the alveolus and is taken to the heart via the pulmonary veins.
