SSTRIDE 2010 Brain Bowl Alrick Drummond, M1 CHAPTER 14: RESPIRATORY SYSTEM

FUNCTIONS OF THE RESPIRATORY SYSTEM Major Functions Air distribution Gas exchange Other functions Filter, warm and humidify air Is also associated with olfaction (smell) and speech

PATH OF AIR (FROM NOSE TO LUNGS) NosePharynxLarynxTracheaLungs

UPPER RESPIRATORY TRACT After the nose receives the air Head colds affect this part of the respiratory system ( Nose, larynx and pharynx ) The pharynx if broken up into different sections Nasopharynx Receives air for surroundings Contains the opening to the auditory (eustachian) tube Help keep pressure equal between the middle and external ear Oropharynx Receives food and air from the mouth The epiglottis stops food from getting into lungs Laryngopharynx Carries air to the trachea towards the lungs Contains the vocal cords

UPPER RESPIRATORY TRACT The trachea begins right under the larynx The trachea Exterior-is made of C shaped cartilage with soft tissue in between them Interior-is lined with respiratory epithelium *cool fact* the esophagus is right behind the trachea and this is why it has C shaped cartilage instead of full rings

PATH OF AIR (INSIDE THE LUNG) Main bronchi Bronchial branches Bronchiole Terminal sacs Alveoli

PATH OF AIR INSIDE THE LUNGS The bronchi continue to branch out into smaller tubes inside the lungs These branches are part of the respiratory tree (remember branches of bronchi make the respiratory tree ) These branches become bronchioles and will end with little elastic sacs called alveoli

ALVEOLI These alveolar sacs are where gas exchange happens via diffusion into the capillaries Gas exchange happens in type I cells in the alveoli Oxygen then binds to the hemoglobin in blood to make oxyhemoglobin which can carry oxygen to the cells Type 2 cels make surfactant, a substance that prevents alveoli for collapsing and reduces surface tension when we breath

BREATHING MUSCLES Eupnea -normal breathing Inspiration Diaphragm External intercostal muscles Expiration Internal intercostal Abdominal muscles *remember that more muscles are used when a person is breathing heavily

LUNG CAPACITY Tidal volume (TV) - the amount of air we normally breath Vital capacity (VC )-the largest amount of air we can breath out at one time Expiratory reserve volume (ERV) -air you can force out after tidal volume Inspiratory reserve volume (IRV) -air you can force in after tidal volume

OTHER IMPORTANT FACTS The epithelium of the lung cells contain an important structure called cilia. These structures can be paralyzed in cigarette smokers There are areas in the blood vessels that detect the amount of oxygen in the blood Carotid body (in the neck) Aortic bodies (in the chest)