Organs and Structures of the Respiratory System

Organs and Structures of the Respiratory System Much of the respiratory system is just for moving air in and out of the lungs. This is called the conducting zone. Here are some the organs involved the conduction zone. 1) The nose is the only part of the respiratory system that you can see. Air enters the nostrils into the nasal cavity where it is warmed, made moist, filtered, cleaned, and scents are detected. 2) Next it passes through the pharynx, which is just a passageway, but it is ringed by tonsils that trap and kill bacteria that enter with the air. 3) The larynx is a doorway. When food is passing through the pharynx, the larynx closes. When we inhale air, it is open and passes through toward the lungs. The larynx also has the vocal cords that make sound for speech. 4) After air passes through the larynx, they enter the trachea. The trachea or windpipe is about 4 inches long (12cm) and is kept open by tiny rings of stiff cartilage. The last ring of cartilage is called the carina and is covered by sensitive tissue. If you inhale anything but air, when it touches the carina, you cough violently until it is gone. This protects the lower airways from being blocked. 5) The trachea splits at the bottom to become the two bronchi, one for each lung. The right and left bronchi enter the lungs and branch many times into smaller and smaller airways: secondary bronchi, tertiary bronchi and finally, tiny bronchioles. Until now the air has just passed through the conducting zone. No gas exchange has occurred. Now it enters the respiratory zone from the bronchioles down to the tiny alveoli, where oxygen exchange occurs. 6) True respiration begins in the smallest bronchioles - the respiratory bronchioles. They branch into alveolar ducts and finally into alveoli. Alveoli look like clusters of tiny grapes. This is where gas exchange occurs. The capillaries that carry oxygen lie right up against the alveoli and form the respiratory membrane. Across this membrane, respiration occurs, when oxygen is traded for carbon dioxide. Organs and Structures of the Respiratory System - Short Answer Quiz 1) The part of the respiratory system that is just for moving air in and out of the lungs is called the _________________________________________________________ zone. 2) The ___________________________________ is the only part of the respiratory system that you can see. 3) Air enters the _________________________________________________ into the nasal cavity where it is warmed, made moist, filtered, cleaned, and scents are detected. 4) Next air passes through the _______________________________________, which is just a passageway, but it is ringed by tonsils that trap and kill bacteria that enter with the air. 5) The ______________________________________ is a doorway. When food is passing down the throat, it closes, but when we inhale air, it is open and it passes through toward the lungs. 6) Then air passes through the ___________________________________ or windpipe is about 4 inches long and is kept open by tiny rings of stiff cartilage. 7) The trachea splits at the bottom to become the two ________________________________, one for each lung. 8) The airways in the lungs branch into smaller and smaller airways until they become narrow ____________________________________________________________________. 9) True respiration begins in these smallest airways, which branch into tiny _____________________________ that look like little clusters of tiny grapes. 10) The capillaries that carry oxygen lie right up against the alveoli and form the ________________________________________________________ membrane. Vocabulary Bank: alveoli bronchi bronchioles conducting larynx nose nostrils pharynx respiratory trachea Structures and Zones of the Respiratory System 1 The nose is the only part of the respiratory system that we can see. Air enters the nostrils into the nasal cavity where it is warmed, moistened, filtered, cleaned, and scents are detected. 2 Next it passes through the pharynx, which is just a passageway, but it is ringed by tonsils that trap and kill bacteria that enter with the air. nostril nasal cavity pharynx air travels into the lungs oral cavity tongue larynx (voice box) 3 The larynx is a doorway. When food is passing through the pharynx, the larynx closes. When we inhale air, the larynx opens for air to pass through toward the lungs. The larynx also has the vocal cords that make speech sounds. trachea to lungs 4 After air passes through the larynx, it enters the trachea or windpipe. The trachea is about 4 inches long (12cm) and is kept open by tiny rings of stiff cartilage. The last ring of cartilage is called the carina and is covered by sensitive tissue. If you inhale anything but air, when it touches the carina, you cough violently until it is gone. This protects the lower airways from being blocked. Structures and Zones of the Respiratory System 5 The trachea splits at the bottom into two bronchi. They each enter a lung and branch into smaller and smaller bronchi and then into even smaller respiratory bronchioles. Respiratory Zone bronchiole alveoli trachea rings of cartilage lungs diaphragm 6 The respiratory bronchioles divide into tiny alveoli. Here oxygen is exchanged for carbon dioxide. This is the respiratory zone. y ar bronchi ll pi ca Conducting Zone