The respiratory system Flashcards
Name the parts of the respiratory system
nasal cavity larynx trachea pharynx epiglottis bronchus bronchiole alveoli rib intercostal muscle diaphragm pleural membranes
what is the function of the nasal cavity?
air passes through into and out of the lungs
it is lined with tiny nasal hairs to trap dust which protects the lungs
what is the function of the pharynx?
it is the passage connecting the nose and mouth to the oesophagus and trachea
what is the function of the epiglottis?
a flap of cartilage that is behind the root of the tongue, which is depressed during swallowing to cover the opening of the windpipe
what is the function of the larynx?
contains the muscles and ligaments of the vocal cords (voice box)
what is the function of the trachea?
it is the tube leading from the pharynx to the lungs, it is supported by strong sections of c shaped cartilage to hold it open during the pressure changes of inspiration and expiration
what is the function of the bronchus?
small branches of the trachea, incomplete rings of cartilage to hold them open. muscular walls to constrict and dilate to vary air. It also contains mucus, which traps dust and pathogens, producing goblet cells. Ciliated epithelial cells remove the mucus
what is the function of the bronchiole?
It is a branch of the bronchus. It has incomplete cartilage rings to hold them open. It also has muscular walls, mucus and ciliated epithelial cells to remove mucus just like the bronchus do
what is the function of the alveoli?
tiny cavity of air sacs of the lungs that allow rapid gaseous exchange. They are moist, thin walled with an excellent blood supply and elastic fibres to withstand pressure changes-Think about how these adaptations could help gas exchange….
What is the function of the ribs?
A series of slender, curved bones that are articulated in pairs (12 pairs), protecting the thoratic cavity and it’s organs.
what is the function of the intercostal muscle?
It runs between the ribs, and it moves the chest wall. The intercostal muscles are mainly involved in the mechanical aspects of breathing. These muscles help expand and shrink the size of the chest cavity to facilitate breathing.
what is the function of the diaphragm?
it is a dome-shaped muscular partition separating the thorax from the abdomen in mammals. It plays a major role in breathing as its contraction increases the volume of the thorax and so it inflates the lungs.
what is the thorax?
between the neck and the abdomen
describe the process of inspiration (breathing in)
the diaphragm and external intercostal muscles contract
the ribs move upwards and outwards, and the diaphragm flattens
this leads to an increase in volume in the thorax, and the pressure decreases to a below atmospheric pressure
air rushes into the lungs, down the pressure gradient
the elastic tissue of the alveoli stretches
the lungs inflate
stretch receptors on the surface of the lungs prevent over inflation
describe the process of expiration (breathing out)
brain stops sending nerve messages to the external intercostal muscles and diaphragm, so they stop contracting
the diaphragm recoils upwards into a domed position, gravity causes the rib cage to drop back downwards
this decreases the volume of the lungs and air pressure in the lungs increases above atmospheric pressure
air is then forced out
