Do Now Read the article and answer the questions

Respiratory System Chapter 16

Objectives To understand the functions of the respiratory system. To identify the major organs and components of the respiratory system.

Functions of the Respiratory System Obtain oxygen and remove carbon dioxide Trap particles (filter) from incoming air and help control the temperature and water content of the air Produce vocal sounds Participate in the sense of smell Regulate blood pH

Events of Respiration Movement of air into and out of lungs (ventilation) Gas exchange between blood and air in the lungs (external respiration) Gas transport in blood between lungs and body cells Gas exchange between blood and cells (internal respiration) *Cellular Respiration: oxygen utilization and carbon dioxide production

Organs of the Respiratory System Upper Respiratory Tract Nose Nasal cavity Paranasal sinuses Pharynx 2. Lower Respiratory Tract Larynx Trachea Bronchial tree Lungs

Idiopathic Pulmonary Fibrosis (IPF) Lungs in a Box Idiopathic Pulmonary Fibrosis (IPF) https://www.youtube.com/watch?v=MJpitXgy0z4

Organs of the Respiratory System

Do Now If you were a doctor trying to measure a patient’s respiratory fitness, what methods could you use to find this out? What kind of factors would you be looking to measure? Would all of your patients have the same measurements? Why or why not?

The Nose Two nostrils- openings in which air can enter and leave, guarded by internal hairs Nasal septum- composed of bone and cartilage, divides the cavity into left and right portions Nasal conchae- bones that curl out, dividing the cavity into passageways. Supports mucous membrane that lines cavity

Mucus Membrane Lines the nasal cavity and helps increase its surface area Contains pseudostratified ciliated epithelium: Goblet cells secrete mucus Blood vessels warm air Incoming air is moistened

Cilia Move thin layer of mucus and entrapped particles toward pharynx Mucus is swallowed and gastric juices destroy microorganisms

Paranasal Sinuses Air-filled spaces located within the skull Reduce the weight of the skull Affect the quality of the voice (resonant chambers)

Pharynx Throat Connects nasal and oral cavity to esophagus Common passageway for: food→ esophagus air→ larynx

Do Now What organs/parts make up a sheep pluck? What’s the purpose of having cartilage rings in the trachea? Are your lungs hollow? If you put a piece of lung in water, do you think it will float or sink?

Larynx Conducts air in and out of trachea Prevents foreign objects from entering Composed of muscle and cartilages Largest are thyroid (“Adam’s apple”), cricoid and epiglottic cartilages P.3, 5

Larynx (cont.) Houses vocal cords (folds of muscle tissue and connective tissue): False vocal cords: do not produce sound, help close airway during swallowing True vocal cords: air forces cords to vibrate = sound Glottis: opening between cords Epiglottis: flap that covers larynx, prevents foods and liquids from entering air passages *Laryngoscopy Video!

Trachea- “Windpipe” Lined by mucus membrane C-shaped cartilage rings (hyaline cartilage) keep passageways open Opening of cartilage is near the back of trachea to allow food to pass through the esophagus Smooth muscle changes the size of the trachea when it contracts

Bronchial Tree Trachea branches into the right and left primary bronchi→ secondary bronchi→ tertiary bronchi → bronchioles Bronchiole: when the bronchi no longer have cartilage they are called bronchioles Asthma Video Clip

Bronchioles lead to Alveoli Respiratory bronchioles open into passageways called alveolar ducts that end at alveolar sacs

Alveoli

Review Animation Review Mouth → Pharynx (throat) → Larnyx (voicebox) → Trachea (windpipe) → Bronchi → Primary, secondary and tertiary Bronchioles → Terminal bronchiole → Alveoli Review Animation

Do Now List the pathway of air beginning with breathing through the nose! P. 6, 3

Objectives To explain the function and necessity of surfactant in the lungs. To explain the differences in pressure during inspiration and expiration. To define the different volumes and capacities within the lungs.

The Lungs Soft, spongy, cone-shaped organs Contain Lobes: Right lung= 3 lobes Left Lung= 2 lobes *Why is the left smaller?? Within the thoracic cavity: Parietal pleural membrane Pleural cavity Visceral pleural membrane

Breathing Vocab Ventilation: breathing Inspiration: inhalation, breathing in Expiration: exhalation, breathing out

Inspiration Atmospheric pressure forces air into the lungs Diaphragm contracts downwards Thoracic cavity enlarges Pressure inside the lungs decreases To equalize pressure, air enters lungs

Surface Tension Inner surface of alveoli attracts water molecules, creates surface tension: alveoli are harder to inflate and can actually collapse Alveolar cells synthesize “surfactant” to fight this and make it easier to inflate the alveoli

Respiratory Distress Syndrome Premature babies do not produce sufficient surfactant and cannot breathe properly Doctors drip synthetic surfactant into their lungs through a tube and they breath using a ventilator

Expiration Elastic recoil of the lung tissue and surface tension of alveoli force expiration Diaphragm relaxes Size of thoracic cavity decreases Surface tension decreases diameter of alveoli Pressure increases inside lungs Air is forced out

Nonrespiratory Air Movements Coughing: airway obstruction in lower respiratory tract causes us to inhale, close the glottis, and force air out, opening the glottis and forcing out the obstruction Sneezing: airway obstruction in upper respiratory tract, air forced through glottis into nasal passage. (can be propelled out at 200mph! Gross!!) Laughing: Taking a breath and releasing it in short expirations Hiccuping: sudden inspiration due to a spasmodic contraction of the diaphragm when the glottis is closed, passing air over vocal cords causes a hiccup sound Yawning: low blood-oxygen concentration triggers yawn reflex that ventilates more of the alveoli

Respiratory Volumes Measure by an instrument called a “spirometer” What are the volumes we covered in lab?

Respiratory Volumes Tidal Volume: volume of air entering or leaving during a single respiratory cycle Inspiratory Reserve Volume: extra air in lungs during forced inspiration Expiratory Reserve Volume: air that exits during forced expiration Residual Volume: air left in lungs even after forced expiration

Respiratory Capacities Combining two or more volumes gives us a capacity: Vital capacity: inspiratory reserve volume + tidal volume + expiratory reserve volume Inspiratory capacity: tidal volume + inspiratory reserve volume Function residual capacity: expiratory reserve volume + residual volume Total Lung Capacity: vital capacity + residual volume (about 5,800 ml)

Respiratory Capacities

Review Which non-respiratory air movement can clear an obstruction from the upper respiratory tract? If you were to completely breath out everything you have in your lungs, what “volume” would still be left in there? What is the name of the substance that allows inflation of the alveoli and is lacking in respiratory distress syndrome?

Respiratory Diseases Read about the respiratory conditions and answer the questions.