Respiratory System Anatomy PDF

Respiratory system Anatomy of the respiratory system Organs in the respiratory system external nose Nasal cavity Nasal cavity Pharynx (throat) Larynx (voice box) Trachea (wind pipe) Bronchi Lungs Respiratory system - often associated...

Respiratory system Anatomy of the respiratory system Organs in the respiratory system external nose Nasal cavity Nasal cavity Pharynx (throat) Larynx (voice box) Trachea (wind pipe) Bronchi Lungs Respiratory system - often associated with breathing ventilation = movement of air in & out the lungs “breathing”   Respiration = di usion of gas across cell membrane ◦ how gas we inhale goes in & in the cell membrane ◦ 2 classi cations: external & internal respiration External respiration is the movement of gas between the air in the atmosphere and in the ✦ lungs & blood Internal respiration is the movement of gas from the blood to the body cells; oxygen and ✦ carbon dioxide will be exchange between the blood and into the cells Anatomically Respiration system can be divided into the upper & lower respiratory tract ◦ Upper respiratory tract = nose, pharynx and larynx ◦ Lower respiratory tract = trachea, bronchi, bronchiole tree, lungs Physiologically Can be redivided into conducting & respiratory zone ◦ Conducting zone = starts from the nose to the smallest air tubes for ventilation for the passage of air ; allows air to go from outside to inside ◦ Respiratory zone = within the lungs and small air tubes for alveoli for gas exchange ; where carbon dioxide & oxygen are exchanged Functions of the respiratory system gas exchange = oxygen and carbon dioxide Regulation of blood ph = alter blood pH by changing blood carbon dioxide levels in which they can manipulate the person to breathe fast or slow ; pH of blood should be maintained at 7.35-7.45 Production of chemical mediators = involves angiotensin converting enzyme which has a role in blood pressure Voice production = where air movement past the vocal chords makes sound and speech possible Olfaction = a special sense because of the nose that contains olfactory epithelium at the root of the nasal cavity Protection = a part of innate immunity because it produces mucus and cilia ; and has epithelium that can protect from harmful pathogens Nose external nose is the visible structure that forms a prominent feature of the face Most external nose is made up of following tissue: ◦ Upper part or the bridge of the nose contains nasal bone ◦ Lower part is softer is made up of hyaline cartilage ◦ The nostrils or nares is the external opening of the nose Parts of the nasal cavity nasal cavity = the space inside the nares ; extends from the nares to the choanae ; starts from the nares all the way down to the choanae ◦ Choanae = opening of the nasal cavity posteriorly and it opens to the pharynx or throat ◦ Vestibule = the area inside the nostrils and where air initially enters ◦ Nasal septum = partition that divides the nasal cavity into left & right parts ◦ Hard palate = oor of nasal cavity and is located anterior which is composed of the maxilla and palatine bone; separates the nasal cavity from the oral cavity ◦ Conchae = 3 structures that resembles a shell or turbine and have 3 parts; for cleansing and humidi cation of the air that we inhale Superior nasal conchae ✦ Middle nasal conchae ✦ Inferior nasal conchae ✦ ◦ Meatus = is the space between conchae Superior nasal meatus = below the superior nasal conchae ✦ Middle nasal meatus = below the middle nasal conchae ✦ inferior nasal meatus = below the inferior nasal conchae ✦ ◦ Nasolacrimal duct = carry tears from the eyes nasal cavity has 2 epithelium linings fi fi fl ff  ◦ Inside the nostrils = strati ed squamous epithelium with coarse hairs to protect in ltering the dust particles ; only the nares is covered by strati ed squamous epithelium ✦ The rest of the nasal cavity is covered with pseudostrati ed columnar epithelial cells that contains cilia which protect you Mucus-producing cells known as the goblet cells will trap particles and humidify the air ✧ ◦ The coarse hairs inside the nares and the mucus produced by the goblet cells will trap large dust particles and prevents you from getting sick ◦ Cilia = little brush like structures on the epithelium will sweep the debris-laden mucus towards the pharynx where it is being swallowed and the acid in the stomach will kill the pathogens Pharynx Common passageway for respiratory and digestive system Air from the nasal cavity & air, food, water from the mouth passes through the pharynx Inferiorly, pharynx takes the lead from the rest of the respiratory system through the opening in the larynx Posteriorly, the opening of the pharynx will open towards the digestive system via esophagus Divided into 3 parts: ◦ Nasopharynx = only for respiratory as only air will move and not food ◦ Oropharynx & laryngopharynx = both digestive & respiratory because food, water & will pass through Nasopharynx located posterior to the choanae and superior to the soft palate Soft palate forms the oor of the nasopharynx and will be elevated during swallowing; movement closes the nasopharynx & prevents food from passing through the oral cavity into the Nasopharynx to prevent choking Pseudostrati ed ciliated columnar epithelium is continuous with the nasal cavity Auditory tube (eustachian tube) extends from the middle ear & opens into the nasopharynx Contains pharyngeal tonsil on the posterior part otherwise known as the adenoid Oropharynx extends from the uvula (a hanging bell structure at the back of the throat) to the epiglottis and the oral cavity opens to the oropharynx. The moment you swallow food and water, it will directly go to the oropharynx It is a strati ed squamous epithelium for protection There are 2 tonsils visible: palatine and lingual ◦ Palatine tonsils = located in the lateral wall near the border of the oral cavity and oropharynx ◦ Lingual tonsil = located on the surface of the posterior part of the tongue Laryngopharynx passes posterior to the larynx and extends from the tip of the epiglottis all the way to the esophagus Food & drink passes through the Laryngopharynx to the esophagus A small amount of air is usually swallowed in with the food and drink Has 2 epithelium linings ◦ Pseudostrati ed ciliated columnar = near the respiratory side ◦ Strati ed squamous epithelium = near the digestive side Larynx commonly called the voice box Located in the anterior throat and extends from the base of the tongue all he way to the trachea or windpipe Has 3 main functions: ◦ Maintains open airway for air to pass ◦ Protects airway during swallowing to prevent from aspiration & choking ◦ Produces the voice fi fi fi fi fl fi fi fi fi  Larynx consists of nine cartilage structures of which 3 are unpaired & 3 paired ◦ Unpaired cartilage ✦ Thyroid cartilage = commonly called the Adam’s apple and is prominent in gentlemen after puberty. It is attached superiorly to the hyoid bone ✦ Cricoid cartilage = located anteriorly, ring-shaped and the most inferior in the laryngeal cartilage; forms the base of the larynx where other cartilages will rest ✦ Epiglottis = tongue shaped that is made up of elastic cartilage Inferior margin is attached to the thyroid cartilage anteriorly; and the superior part of the ✧ epiglottis projects superiorly as a free ap towards the tongue ✦ Signi cance of the free ap characteristic = every time you swallow, the epiglottis protects the airway by covering the opening of the larynx or glottis to prevent swallowing food in the respiratory system fi fl fl  ◦ Paired cartilage = located in the posterior side of the larynx since the main function of the paired cartilage is the attachment of the vocal folds   Cuneiform = wedge-shaped and is located in the top or most superior of the paired ✦ cartilage Corniculate = horn-shaped is located in the middle ✦ Arytenoid = shaped like a ladle and is the one who will articulate with the cricoid cartilage ✦ at the inferior part Vocal chords 2 types of vocal chords in the larynx Larynx is called the voice box because every time you speak, they need to vibrate False vocal cords = superior set of ligaments or often called vestibular fold prevents air from leaving the lungs as when the person holds his or her breath and also prevent food and liquids from entering the larynx ◦ Only for covering since it doesn’t vibrate and the reason why it’s called false vocal cords True vocal cords = also called vocal folds is the ligaments that is capable of voice production since it is the only one that vibrates when air passes through ◦ When air passes through the vocal fold, they produce sound, the muscles of the larynx control the lenght and tension of the vocal folds and the force of air that moves past the vocal folds controls the loudness and tension controls the pitch Trachea also known as the windpipe and is a membranous tube about 10-11 cm 1.4-1.6 cm in diameter Is a pseudostrati ed columnar epithelium which contains numerous cilia and goblet cells Made up of connective tissue and smooth muscle that is reinforced with 16-20 C-shaped pieces of hyaline cartilage in anterior and lateral then elastic membrane at posterior Begins immediately inferior to the cricoid cartilage then divides into right and left primary bronchi at the level of the fth thoracic vertebrae called carina ◦ In the book, carina is located between T4 - T5 and posterior to the trachea is the esophagus Bronchi Starts from the cricoid and divides into left and right main bronchi or primary bronchi that connects to the lungs ◦ Emphasize main or primary bronchi since it is the part directly to the carina Left main bronchus = is more horizontal than the right main bronchus since it is displaced by the heart Foreign objects that enters the trachea usually lodge in the right main bronchus since it is wider, shorter and more vertical compared to the left main bronchus and is more in direct line with the trachea Bronchi are lined with pseudostrati ed ciliated columnar epithelium and are supported by c- shaped pieces of cartilage Lungs the principal organs of respiration Each lung cone-shaped with a base resting on the diaphragm and the apex will extend superiorly about an inch or 2.5 cm above the rst rib Right lung has 3 lobes and 2 ssures ◦ Superior lobe ◦ Middle lobe ◦ Inferior lobe ◦ Oblique ssure ◦ Horizontal ssure Left lung has 2 lobes and 1 ssure ◦ Superior lobe ◦ Inferior lobe fi fi fi fi fi fi fi fi  ◦ Oblique ssure ✦ Left lung also contains a depression which is called cardiac notch and is the place where the heart lodge fi   each lobe of the lungs is divided into bronchopulmonary segments and are separated from one another by connective tissue septa; but the separation is not visible as surface ssures Each bronchopulmonary segments will contain major blood vessels and bronchi that doesn’t cross the septa Individual diseased bronchopulmonary segments can be surgically removed which leaves the rest of the lung relatively intact ◦ Bronchopulmonary segments are autonomous or works together but have independent bronchi that carries the lung Right lung has 10 bronchopulmonary segment and left has 9 fi   Tracheobronchial tree   Tracheobronchial tree consists of the main bronchi and many branches Each main bronchi will divide into lobar bronchi or also called secondary bronchi and enters into the respective lungs to conduct air to each lobe ◦ Right lung has 3 lobes which means that it will have 3 lobar bronchi for air to pass through ◦ Left lung has 2 lobes so it will have 2 lobar bronchi that facilitates entry of air The lobar bronchi in each of the right and left lung will divide into segmental bronchi or the tertiary bronchi ◦ The tertiary bronchi will lead to bronchopulmonary segment of the lungs ◦ Right lung has ten bronchopulmonary segment which means that it will get 10 segmental bronchi ◦ Left lung has 9 which means that it will get 9 segmental bronchi Bronchi will continue to branch many times like a tree and then will give rise to bronchioles which are smaller Bronchioles will subdivide numerously in order to give rise to terminal bronchioles ◦ Terminal bronchioles will now subdivide to respiratory bronchioles ◦ Respiratory bronchiole will subdivide to form alveolar ducts that will lead to the alveoli Alveoli small air- lled chambers where the air and blood come into close contact with each other Alveoli is so numerous that the alveolar duct wall is little more than a succession of alveoli There are about 300 million of alveoli in the lungs Alveolar duct will lead to 2 or 3 alveolar sacs that are chambers connected to 2 or more alveoli Has two types of cells: type I & type II pneuomocytes ◦ Type I Pneumocytes = is made up of simple squamous for gas exchange ◦ Type II Pneumocytes = is the one that produces surfactant fi   Respiratory membrane located in the alveoli itself Formed mainly by the walls of the alveoli and the surrounding capillaries that brings supply Is Where gas exchange between air and blood takes place; it should be thin Consists of 2 layers of simple squamous epithelium which includes secreted uid called alveolar uid and that separates the spaces It has elastic bers that allows the alveoli to expand during inspiration and recoil during expiration Layers of the respiratory membrane 6 Layers from lungs to blood vessel thin layer if alveolar uid followed by The alveolar epithelium which is made up of simple squamous epithelium Third layer is the basement membrane from where the simple squamous epithelium will attach Next is the thin interstitial space (the space between the blood and blood vessels which is the capillaries Then the basement membrane of the capillary endothelium Capillary endothelium which are made up of the simple squamous epithelium Thoracic wall made up of thoracic vertebrae posteriorly Made up of 12 ribs laterally Anteriorly, it is made up of the sternum which is the breastbone Costal cartilages; 7 of which are connected to the sternum and is Surrounded by the muscles of inspiration like the diaphragm, external intercoastals, pectoralis minor, scalenr muscles (attach to the rst and second rib) Muscles of expiration that are found in the thoracic wall: internal intercoastal and transversus thoracis Pleural cavities inside the thorax is a cavity where lungs are located Each pleural cavity is lined with a serous membrane called pleura ◦ 2 types of pleura: parietal and visceral pleura ✦ Parietal pleura = covers the wall of the thorax, diaphragm and mediastinum ✦ Visceral pleura = covers the surface of the lungs Pleural cavity between the parietal and visceral pleura contains a small volume of pleural uid which is produced by the pleural membranes Pleural uid will serve to perform 2 di erent functions ◦ Act as a lubricant when you inhale and every time it expands it won’t be painful ◦ Holds the pleural membrane together fl fl fi fl ff fi fl fl