Respiratory System Structures PDF

Outcome D1b Explain how the human respiratory system exchanges energy and matter with the environment. Respiratory System Structures Outcome D1b, Lesson 1 Air Air consists of: Nitrogen Carbon dioxide Oxygen Argon Trace gases We obtain oxygen through breathin...

Outcome D1b Explain how the human respiratory system exchanges energy and matter with the environment. Respiratory System Structures Outcome D1b, Lesson 1 Air Air consists of: Nitrogen Carbon dioxide Oxygen Argon Trace gases We obtain oxygen through breathing in air to our lungs The absence of oxygen from more than just a few minutes can result in death Why do we need to breathe? Oxygen is needed by each cell of the body for cellular respiration Carbon dioxide is a by-product of cellular respiration and is not used by our cells (waste product) It is harmful to the body in high concentrations Main function of the respiratory system: Take in oxygen and release carbon dioxide into the environment Respiration Requirements The two main requirements for respiration to take place Large surface area To maximize the rate at which oxygen and carbon dioxide can be exchanged Moist environment To dissolve oxygen and carbon dioxide so they can diffuse across the membrane The Respiratory Tract The lungs are the main organ of respiration Located in the thoracic cavity Thoracic is Greek for “chest plate” The passageway of air in and out of the lungs is called the respiratory tract Divided into upper and lower respiratory tract Respiratory Tract – Upper 1. Nasal Passage Warms, moistens, and cleans incoming air Lined with ciliated cells Ciliated cells: cells covered in microscopic hairs Action of ciliated cells moves foreign particles back up the nose and throat Other cells secrete mucous Traps particles like dust and bacteria Moistens air Turbinate bones project into nasal cavity Increase surface area Covered in cilia Heat from blood vessels heats the air Respiratory Tract – Upper Respiratory Tract – Upper Nasal Passage Respiratory Tract – Upper 2. Pharynx Common passageway for air and food Often called the throat Part of respiratory and digestive systems 3. Epiglottis Flap that covers the opening to the trachea 4. Glottis Opening to the trachea Must be covered when swallowing so food in not inhaled Respiratory Tract – Upper Respiratory Tract – Upper Pharynx Epiglottis Glottis Respiratory Tract – Upper 5. Larynx Also called voice box Made from cartilage and contains vocal cords Vocal cords contract and vibrate when you speak Pitch varies based on how long the cords are Longer cords = lower sound Shorter cords = higher sound Respiratory Tract – Upper Respiratory Tract – Upper Larynx Respiratory Tract – Upper 6. Trachea Also called the windpipe Carries air to the lungs Flexible strengthened and supported by semicircular rings of cartilage Prevent it from collapsing Respiratory Tract – Upper Respiratory Tract – Upper Trachea Respiratory Tract – Lower 7. Bronchi (singular: bronchus) Just above the heart, the trachea branches into two bronchi One to left lung, other to right lung Supported by C-shaped cartilaginous rings stacked one on the next Provide support Lined with cilia and mucous producing cells Respiratory Tract – Lower 8. Bronchioles Subdivisions of bronchi within each lung Do not contain cartilage Also lined with cilia and mucous producing cells Respiratory Tract – Lower Respiratory Tract – Lower Bronchi Bronchioles Respiratory Tract – Lower 9. Alveoli (singular: alveolus) Found at the end of terminal (last) bronchioles Tiny clusters of air sacs About 300 million of alveoli in one pair of lungs! Site of gas exchange Alveolar wall is one cell thin and surrounded by a net of capillaries Respiratory Tract – Lower 9. Alveoli (singular: alveolus) Specialized for optimal diffusion Moist membrane Large surface area Thin walls Immediately next to pulmonary capillaries Inner surface covered with a layer of lipids called surfactant Keeps them from collapsing and prevents their sides from sticking together and closing Respiratory Tract – Lower Respiratory Tract – Lower Alveolus Respiratory Tract – Lower 10. Lungs Primary organ of the respiratory system Divided into lobes Right lung has three lobes Left lung has only two lobes (to make room for the heart) 11. Pleural Membrane A thin, fluid-filled double membrane that surrounds the lungs Allows the lungs to expand and contract with the movement of the chest Respiratory Tract – Lower Respiratory Tract – Lower Pleural Lung Membrane Respiratory Tract – Lower 12. Diaphragm A dome-shaped layer of muscle that separates the lungs (thoracic cavity) from the stomach and liver (abdominal cavity) Works with rib muscles to move air in and out of the lungs Respiratory Tract – Lower Respiratory Tract – Lower Diaphragm