Respiratory Anatomy May 5, 2010 Notes from Lab and Dissection

General Functions of the System Ventilation (breathing) – the entrance and exit of air into and out of the lungs Ventilation (breathing) – the entrance and exit of air into and out of the lungs External respiration – the exchange of gases (carbon dioxide and oxygen) between the air and blood External respiration – the exchange of gases (carbon dioxide and oxygen) between the air and blood Internal respiration – the exchange of gases between the blood and tissue fluid Internal respiration – the exchange of gases between the blood and tissue fluid Transport – of gases to and from the lungs and the tissues Transport – of gases to and from the lungs and the tissues

Anatomy and the flow of air: The Nose / Nasal passages begin to cleanse the air with course hairs inside the nostrils and continue to do so with cilia and mucus in the nasal cavities. The Nose / Nasal passages begin to cleanse the air with course hairs inside the nostrils and continue to do so with cilia and mucus in the nasal cavities. Air warmed by the blood vessels lying close to the surface of the lining of the airways. Air warmed by the blood vessels lying close to the surface of the lining of the airways. Air is moistened by the mucus epithelium that lines most of the air passages. Air is moistened by the mucus epithelium that lines most of the air passages. Conversely, as air leaves the body it deposits its moisture along the way. This can cause the nose to drip and is what is responsible for you being able to see your breathe on a cold day. Conversely, as air leaves the body it deposits its moisture along the way. This can cause the nose to drip and is what is responsible for you being able to see your breathe on a cold day.

Nose and Nasal Cavity 2 Nostrils 2 Nostrils 2 Nasal cavities separated by a septum composed of bone and cartilage. 2 Nasal cavities separated by a septum composed of bone and cartilage. Conchae are bony ridges that project out laterally trapping air and increasing surface area for moistening and warming. Conchae are bony ridges that project out laterally trapping air and increasing surface area for moistening and warming. Lacrimal glands (tear) drain into the nasal cavity which is why your nose runs when you cry. Lacrimal glands (tear) drain into the nasal cavity which is why your nose runs when you cry. Nasal cavity is separated from the oral cavity by the hard and soft palate. Nasal cavity is separated from the oral cavity by the hard and soft palate.

Pharynx Broken into three parts: nasopharynx, oropharynx, and laryngopharynx. Broken into three parts: nasopharynx, oropharynx, and laryngopharynx. The tonsils form a protective ring around the pharynx – this is lymphatic tissue that protects against the invasion of inhaled pathogens. The tonsils form a protective ring around the pharynx – this is lymphatic tissue that protects against the invasion of inhaled pathogens. It is the junction of air and food passage. The esophagus remains closed by the epiglottis unless a person is swallowing. It is the junction of air and food passage. The esophagus remains closed by the epiglottis unless a person is swallowing.

Larynx A cartilaginous structure A cartilaginous structure Contains the Adam’s Apple Contains the Adam’s Apple Called the voice box because it contains the vocal cords. Called the voice box because it contains the vocal cords. The vocal cords are mucosal folds supported by elastic ligaments, and the opening between them is the glottis. The vocal cords are mucosal folds supported by elastic ligaments, and the opening between them is the glottis. When air is expelled past the vocal cords through the glottis the cords vibrate producing sound. The greater the tension on the cords and the narrower the glottis, the higher the pitch. When air is expelled past the vocal cords through the glottis the cords vibrate producing sound. The greater the tension on the cords and the narrower the glottis, the higher the pitch.

Trachea Tube with c-rings of cartilage. The open part of the c is facing the esophagus – why do you think this is? Tube with c-rings of cartilage. The open part of the c is facing the esophagus – why do you think this is? Lined with pseudostratified ciliated columnar epithelium. Cilia beat upward moving the particles out of the system. Goblet cells produce mucus to trap debris. Lined with pseudostratified ciliated columnar epithelium. Cilia beat upward moving the particles out of the system. Goblet cells produce mucus to trap debris. Smoking destroys the cilia causing soot from smoking to get caught in the lungs. Smoking destroys the cilia causing soot from smoking to get caught in the lungs.

Bronchial Tree Contains the same histology as the trachea. Divides trachea into right and left primary bronchi. Contains the same histology as the trachea. Divides trachea into right and left primary bronchi. Branches into a large number of secondary bronchi that eventually lead to bronchioles – rings of cartilage are no longer present. Branches into a large number of secondary bronchi that eventually lead to bronchioles – rings of cartilage are no longer present. During an asthma attack, the smooth muscle of the bronchioles contracts, causing constriction and wheezing. During an asthma attack, the smooth muscle of the bronchioles contracts, causing constriction and wheezing. Each bronchiole leads to an elongated space enclosed by a bunch of air pockets called alveoli. Each bronchiole leads to an elongated space enclosed by a bunch of air pockets called alveoli.

Lungs Paired, cone-shaped structures. Paired, cone-shaped structures. The right lung has 3 lobes and the left, 2. The lobes are divided further into lobules which each have a bronchiole serving many alveolar sacs. The right lung has 3 lobes and the left, 2. The lobes are divided further into lobules which each have a bronchiole serving many alveolar sacs. Diaphragm sits inferiorly to the lungs. Diaphragm sits inferiorly to the lungs. Each lung is enclosed by a pleural sac (serous membrane). Each lung is enclosed by a pleural sac (serous membrane).

Alveoli Composed of simple squamous epithelium and is surrounded by capillaries which are also composed of simple squamous. What major function does the structure of simple squamous allow? Composed of simple squamous epithelium and is surrounded by capillaries which are also composed of simple squamous. What major function does the structure of simple squamous allow? Alveoli are covered in surfactant, a lipoprotein that allows them not to collapse under the pressure of water surface tension. Alveoli are covered in surfactant, a lipoprotein that allows them not to collapse under the pressure of water surface tension.