The Respiratory System

1. The Respiratory System By: ValentinaEcheverry, Nicole Delgado, David Raza, Alexandra Ocasio

2. Functions of the Respiratory System: • Performs gas exchange -- converts oxygen  carbon dioxide 2. Inspiration and expiration -- breathing in and breathing out  air is conducted toward or away from the lungs. 3. Respiratory system works with the cardiovascular system to accomplish 4 respiratory systems -- pulmonary ventilation -- external respiration -- internal respiration --transport of gases

3. Four Events: Pulmonary Ventilation  The entrance and exit of air into and out of the lungs. External respiration  the exchange of gases between air and blood. Internal respiration  the exchange of gases between blood and tissue fluid. Transport of Gases  to and from the lungs and the tissues.

4. The Respiratory tract: • Nasal cavity • Nostril • Pharynx • Epiglottis • Glottis • Larynx • Trachea • Right & Left bronchus • Bronchiole • Lung • Diaphragm • Pulmonary Venue • Pulmonary Arteriole • Alveolus • Capillary Network

6. Upper Respiratory Tract: • Nasal cavities • Pharynx • Glottis • Larynx -- Nasal Cavities: Hollow spaces in nose; filter, warm and moisten air -- Pharynx: Lies between nasal cavity and larynx; connection to surrounding regions -- Glottis: Opening into larynx; passage of air into larynx -- Larynx: Voice box; sound production

8. Lower Respiratory System: • Trachea • Bronchi • Lungs • Alveoli • Pulmonary Capillaries -- Trachea: Tube that connects larynx with bronchi; passage of air to bronchi -- Bronchi: Paired tubes that enter the lungs; passage of air to lungs -- Lungs: Organs that occupy lateral portions of thoracic cavity; gas exchange -- Alveoli: Air sacs that branch from bronchioles; passage of into and out of pulmonary capillaries -- Pulmonary Capillaries: Capillaries that cover surface of alveoli; receive oxygen, deliver CO2 from tissues to alveoli

9. The Nose • A prominent feature of the face • Only external part of respiratory system. • Air enters the body though external openings called nostrils. • The nose contains two nasal cavities, separated from one another by a septum. • The nasal cavities are lined with mucus membranes. • The nasal cavities also communicate with paranasal sinuses. They are air filled spaces that reduce the size and the weight of the skull

10. The Pharynx • Funnel- shaped passageway that connects the nasal and oral cavities to the larynx. • The pharynx is referred to as the throat. • Has three parts - The nasopharynx where nasal cavities open posteriorto the soft palate. • The oropharynx  where the oral cavity joins the pharynx • The laryngopharynx  opens into the pharynx • The soft palate has a soft extension called the uvula. • The single pharyngeal tonsil (adenoid) helps defend against infection. • In the pharynx, the air passage and the food passage cross because the larynx, which receives air, is anterior to the esophagus which receives food. - Larynx and trachea are normally opened allowing air in while the esophagus is normally collapsed and opens only when the person swallows.

11. The Larynx • A cartilaginous structure that serves as a passageway for air between the pharynx and trachea. • The vocal cords are mucosal folds supported by elastic ligaments, and the slit between the vocal cords is an opening called the glottis. • When food is swallowed, the larynx moves upward against the epiglottis, a flap of elastic cartilage that prevents food from passing through the glottis into the larynx.

12. The Trachea • Commonly known as the windpipe. • Tube connecting the larynx to the primary bronchi. • Trachea lies ventral to the esophagus and is held open by C-shaped cartilaginous rings. • The C-shaped rings allows the esophagus to expand when swallowing. • The mucosa that lines the trachea has a layer of cilia that project from the epithelium keep the lungs clean by sweeping mucus toward the pharynx. • Fun Fact: Smoking is known to destroy this cilia, and the soot collects in the lungs. • Tracheostomy may be done if the trachea is blocked by making an incision in the trachea.

13. The Bronchial Tree • The trachea is divided into the left and right bronchi. Which leads into the left and right lungs. • Bronchioles-smallest conducting airways • Fun Fact During an Asthma attack, the smooth muscle of the bronchioles contracts causing constriction and wheezing.

15. The Lungs • Paired cone-shaped organs • Both are separated by the mediastinum • The apex is the superior, narrow portion of the lung. • The base is the inferior broad portion that curves to fit the dome-shaped diaphragm. • Each lobe of the lung is further divided into lobules, each lobule has a bronchiole supplying many alveoli. • Pulmonary capillaries surround and cover each alveolus of the lung. • Elastic connective tissue binds the air passages to the blood vessels within each lung. • Which helps the lungs return to their resting position, or recoil when a person exhales. • The pleurae is a serious membrane in which each lung is enclosed within. • Serous fluid creates surface tension: the tendency for water molecules to cling to each other and to form a droplet. It also holds the two pleural layers together which holds the lungs open against the chest wall.

17. The Alveoli • With each inhalation, air passes by way of the bronchial tree to the alveoli. • Each aveolus is covered with an extremely thin layer of water-based tissue fluid. • Infant respiratory distress syndrome- now treatable surfactant replacement therapy.

18. Pause: • ACTIVITY :D

19. Respiratory Membrane • Consists of the juxtaposed alveolar epithelium and the capillary endothelium. • Very little tissue fluid separates the two portions of the respiratory membrane. • A person with emphysema has a reduced amount of respiratory membrane.

20. Ventilation • Ventilation: the manner in which air enters and exits the lungs • Inspiration: • Active phase of ventilation • Phase in which the diaphragm and the external intercostal muscles contract • The ribcage moves up and outward during the process of inspiration. • Flow of air into the alveoli is passive

21. Ventilation continued • Expiration: • Passive phase of ventilation– no muscular effort is required • Diaphragm resumes its dome shape and the rib cage moves down and in.

22. Respiratory Volumes • When we are relaxed the amount of air is called the tidal volume. • The maximum volume of air during a single breath is called the vital capacity. • Forced inspiration is called the inspiratory reserve volume. • In an adult 70% of the tidal volume reaches the alveoli but 30% remains in the airways. This is called dead space air.

23. Control of Ventilation • The basic rhythm of ventilation is controlled by a primary respiratory center located in the medulla oblongata. • Nervous input- Observation of ones own breathing patterns influences the brain. • Chemical input- The respiratory center is sensitive to the levels of carbon dioxide, and hydrogen ions. When they rise rate and depth of breathing increases.

25. Upper Respiratory Tract Infections • Sinusitis- infection of the cranial sinuses, the cavities within the facial skeleton that drain into the nasal cavities. • Otitis Media- bacterial infection of the middle ear. • Tonsillitis- When the tonsils become inflamed and enlarged. • Laryngitis- inflammation of the larynx, leading to the inability to talk in an audible voice.

26. Lower Respiratory Tract Infections • Acute bronchitis- infection of the primary and secondary bronchi. • Pneumonia- a viral or bacterial infection of the lungs in the which the bronchi and alveoli fill with thick fluid. • Pulmonary tuberculosis- caused by the tubercle bacillus, a type of bacterium. They invade the lung tissue isolating them from the rest of the body.

28. The End: • Quiz Time!